26.02.2015 Views

microbiological investigation of raw goat milk from commercial dairy ...

microbiological investigation of raw goat milk from commercial dairy ...

microbiological investigation of raw goat milk from commercial dairy ...

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

MICROBIOLOGICAL INVESTIGATION OF RAW GOAT MILK FROM<br />

COMMERCIAL DAIRY GOAT FARMS IN BOGOR, INDONESIA<br />

EPI TAUFIK<br />

MASTER OF VETERINARY PUBLIC HEALTH<br />

CHIANG MAI UNIVERSITY AND FREIE UNIVERSITÄT BERLIN<br />

SEPTEMBER 2007


MICROBIOLOGICAL INVESTIGATION OF RAW GOAT MILK FROM<br />

COMMERCIAL DAIRY GOAT FARMS IN BOGOR, INDONESIA<br />

EPI TAUFIK<br />

A THESIS SUBMITTED TO CHIANG MAI UNIVERSITY AND FREIE<br />

UNIVERSITÄT BERLIN IN PARTIAL FULFILLMENT OF THE<br />

REQUIREMENTS FOR THE DEGREE OF<br />

MASTER OF VETERINARY PUBLIC HEALTH<br />

CHIANG MAI UNIVERSITY AND FREIE UNIVERSITÄT BERLIN<br />

SEPTEMBER 2007


iii<br />

ACKNOWLEDGEMENTS<br />

First, I would like to express my sincere gratitude to my thesis advisory<br />

committee. These are Univ. Pr<strong>of</strong>. Dr. Goetz Hildebrandt and Dr. Josef Nikolaus<br />

Kleer at the Institute <strong>of</strong> Food Hygiene, Faculty <strong>of</strong> Veterinary Medicine, Freie<br />

Universität Berlin (FUB), Germany, and also Dr. Tri Indrarini Wirjantoro at the<br />

Department <strong>of</strong> Food Science and Technology, Faculty <strong>of</strong> Agro-Industry, and<br />

Assist. Pr<strong>of</strong>. Dr. Khwanchai Kreausukon at Veterinary Public Health Center for Asia<br />

Pacific, Faculty <strong>of</strong> Veterinary Medicine, Chiang Mai University (CMU), Thailand; as<br />

well as my country advisor, Pr<strong>of</strong>. Dr. Fachriyan H. Pasaribu, at the Department <strong>of</strong><br />

Animal Diseases and Veterinary Public Health, Faculty <strong>of</strong> Veterinary Medicine,<br />

Bogor Agricultural University (BAU), Indonesia. Without their precious advice and<br />

continuous encouragement, this thesis would not have been completed. I wish to<br />

express my real gratitude to them again.<br />

I also wish to express my high appreciation and thanks to the administration <strong>of</strong><br />

this program, both <strong>from</strong> FUB and CMU. I would like to thank Univ. Pr<strong>of</strong>. Dr. Karl<br />

Hans Zessin, Dr. Maximilian Baumann and their staff in Germany, Assoc. Pr<strong>of</strong>. Dr.<br />

Lertrak Srikitjakarn, Assist. Pr<strong>of</strong>. Dr. Khwanchai Kreausukon, Dr. Anucha<br />

Sirimalaisuwan, Assist. Pr<strong>of</strong>. Dr. Pawin Padungtod, and their staff in Thailand.<br />

I would like to thank the German Government via DAAD, EU Asian Link Project and<br />

the Thai Government via VPHCAP for providing me a great financial support.<br />

I am greatly indebted to all the teachers and assistants within this Joint Master<br />

Program in Veterinary Public Health <strong>from</strong> CMU, FUB and Veterinärmedizinische<br />

Universität Wien (VUW), Austria; for their critical comments, knowledge and<br />

experience-sharing as well as their friendship and cooperation. Special thanks goes to<br />

Pr<strong>of</strong>. Dr. Reinhard Fries, Dr. Moses Kyule, Assist. Pr<strong>of</strong>. Dr. Pawin Padungtod and<br />

Dipl.-Stat. Rose Schmitz for their critical insight, statistical advice and<br />

encouragement. I also would like to extend my gratitude to Assist. Pr<strong>of</strong>. Dr. Peter<br />

Paulsen and his staff at Institute <strong>of</strong> Meat Hygiene, Meat Technology and Food


iv<br />

Science VUW, Austria, for their guidance in introducing me to the advance laboratory<br />

techniques on food microbiology.<br />

My sincere gratitude also goes to Mrs. Nancy Huber for her great assistance in<br />

editing the english language <strong>of</strong> my thesis. I am also grateful to all my friends in the<br />

second batch <strong>of</strong> the MPVH program, we spent a long time together during this study<br />

period. I hope our friendship will last forever.<br />

To the librarian <strong>of</strong> Faculty <strong>of</strong> Veterinary Medicine Library, either <strong>from</strong> CMU<br />

Thailand or FUB, Germany, your cooperation and kindly assistance were highly<br />

appreciated.<br />

It was a great experience for me to have a wonderful stay in Berlin. Therefore<br />

I would like to thank Dr. Norbert Miethe, Mrs. Louise Le Bel, Ms. Juliane Fischer,<br />

my Indonesian friends in Berlin, especially Jamaah Masjid Al Falah Berlin, Pak<br />

Bram and family, Pak Han and family, Pak Ali, Fahmi, Lingga, Nanda, Hasan, Husein<br />

and Firdaus as well as Pak Muis family in Hamburg, for their kind assistance,<br />

experience-sharing and friendship.<br />

I equally enjoyed my staying period in Chiang Mai. To Ms. Jariya Yos-I,<br />

Ms. Supheerutai Buakaew, Ms. Saowaluck Prommin, Ms. Manatchaya U-tairat,<br />

Ms. Nattakarn Awaiwanont, Phi Noy, Phi On, Phi Dang, Phi Tiauw, Phi S, Nuke,<br />

Eddy, Lucas, Poo, Ronny and Ibu Susi, I thank you for all your whole-hearted support<br />

and kindness during my stay in Chiang Mai, Thailand.<br />

To the Rector, Vice Rector for academic affairs and International Program<br />

Office staff as well as the Dean <strong>of</strong> Faculty, the Head <strong>of</strong> Department, the Head <strong>of</strong><br />

Laboratory, my seniors and colleagues <strong>from</strong> the Faculty <strong>of</strong> Animal Science and the<br />

Faculty <strong>of</strong> Veterinary Medicine, BAU, Indonesia; your continuous support is highly<br />

appreciated. I would also like to thank the farm owners for the cooperation in<br />

allowing their animals to be accessed for sample collection. Thanks to farm workers<br />

for assisting me in sample collection and also to Pak Agus, Pak Raffi, Selyn and<br />

Abenk for laboratory work.


v<br />

This thesis is dedicated to my beloved family; my late father, mom, my<br />

parents-in-law, my elder brother and his wife and their beloved children and also to<br />

my younger brother. Thank you very much for supporting me spiritually, emotionally<br />

and otherwise. Special dedications to my beloved wife, Nurhayati and our daughter<br />

Aisyah Nur Taufik, as well as our next baby, without them I think I would never have<br />

achieved this step. Thank you for the constant support, words <strong>of</strong> encouragement you<br />

provided and an endless love as well as the patience you showed when I left all <strong>of</strong> you<br />

towards completion <strong>of</strong> this endeavor. May The Almighty release a wonderful blessing<br />

to all <strong>of</strong> us, I love you all.<br />

Lastly, utmost thanks is due to my God, Allah SWT, The Creator <strong>of</strong> mankind<br />

and universe. Without His willing, blessing and guidance, it would be impossible for<br />

me to face and go through this challenging step in my life.<br />

Epi Taufik


vi<br />

Thesis Title<br />

Author<br />

Degree<br />

Microbiological Investigation <strong>of</strong> Raw Goat Milk <strong>from</strong><br />

Commercial Dairy Goat Farms in Bogor, Indonesia<br />

Mr. Epi Taufik<br />

Master <strong>of</strong> Veterinary Public Health<br />

Thesis Advisory Committee Pr<strong>of</strong>. Dr. Goetz Hildebrandt Chairperson (FU-Berlin)<br />

Dr. Tri Indrarini Wirjantoro Chairperson (CMU)<br />

Asst. Pr<strong>of</strong>. Khwanchai Kreausukon Member (CMU)<br />

ABSTRACT<br />

Investigation on <strong>microbiological</strong> quality such as Total Plate Count (TPC),<br />

coliforms and the presence <strong>of</strong> pathogenic bacteria <strong>of</strong> <strong>goat</strong> <strong>milk</strong>, together with some<br />

risk factors affecting these microorganisms in Indonesia, was very rare. In view <strong>of</strong><br />

food hygiene and consumer health as well as animal health protection, however,<br />

evaluation <strong>of</strong> the <strong>microbiological</strong> status and presence <strong>of</strong> pathogenic bacteria in <strong>goat</strong><br />

<strong>milk</strong>, which can cause adverse health effects on the animals as well as pose a high risk<br />

<strong>of</strong> causing foodborne disease in humans, is <strong>of</strong> central importance. Therefore this study<br />

was aimed at investigating the <strong>microbiological</strong> quality <strong>of</strong> <strong>raw</strong> <strong>goat</strong> <strong>milk</strong> by using<br />

indicator bacteria, and also to evaluate the potential risk factors associated with them.<br />

Information regarding potential risk factors was collected by questionnaire.<br />

The conventional bacteriological method for bacteria isolation and the indirect test<br />

(California Mastitis Test (CMT)) for determining udder inflammation status were<br />

employed. A sample size <strong>of</strong> 300 udder halves and 30 bulk <strong>milk</strong> samples <strong>from</strong> three<br />

<strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms in the Bogor District, West Java Province, Indonesia<br />

were investigated for counts and prevalence <strong>of</strong> indicator bacteria, which were TPC,<br />

coliforms, Staphylococcus spp., Coagulase Positive Staphylococci (CPS) and<br />

Coagulase Negative Staphylococci (CNS). Ten potential risk factors were also<br />

evaluated in relation to counts and prevalence <strong>of</strong> indicator bacteria.


vii<br />

The median values <strong>of</strong> indicator bacterial counts <strong>from</strong> overall udder-half <strong>milk</strong><br />

samples were 3.74, 0.70, 3.00, 1.70 and 2.52 log cfu/ml and <strong>from</strong> bulk <strong>milk</strong> samples<br />

were 5.69, 2.98, 3.86, 3.66 and 3.32 log cfu/ml for TPC, coliforms, Staphylococcus<br />

spp., CPS and CNS, respectively.<br />

The indicator bacterial counts <strong>from</strong> udder-half <strong>milk</strong> samples were significantly<br />

different (P


viii<br />

ชื่อเรื่องวิทยานิพนธ การสํารวจทางจุลชีววิทยาของน้ํานมแพะดิบจากฟารม<br />

แพะนมในบอกอร อินโดนีเซีย<br />

ผูเขียน นาย เอ ป ทาล ฟค<br />

ปริญญา<br />

สัตวแพทยสาธารณสุขศาสตรมหาบัณฑิต<br />

คณะกรรมการที่ปรึกษาวิทยานิพนธ ศ.ดร.โกส ฮิลเดอร บรานซ ประธานกรรมการ (FU- Berlin)<br />

ดร. ไตรอินดรารินี่ วีจานโตโร ประธานกรรมการ (CMU)<br />

ผศ. ขวัญชาย เครือสุคนธ กรรมการ (CMU)<br />

บทคัดยอ<br />

การสํารวจคุณภาพทางจุลชีววิทยาอยางเชน Total Plate Count (TPC), coliforms<br />

และการพบแบคทีเรียกอโรคของน้ํานมแพะและปจจัยที่เกี่ยวของในอินโดนีเซียมีนอยมาก<br />

ในดานสุขศาสตรอาหารและสุขภาพผูบริโภคนั้น การประเมินสถานะทางจุลชีววิทยาและการพบ<br />

แบคทีเรียกอโรคของน้ํานมแพะที่กอใหเกิดผลตอสุขภาพสัตวและยังกอใหเกิดความเสี่ยงตอการเกิด<br />

โรคในคนจากอาหารเปนเรื่องที่มีความสําคัญอยางมาก ดังนั้นการศึกษาในครั้งนี้มีจุดมุงหมายที่<br />

การสํารวจคุณภาพทางจุลชีววิทยาของนมแพะดิบโดยใชเชื้อแบคทีเรียเปนตัวชี้วัด<br />

และประเมินปจจัยเสี่ยงที่มีผลตอคุณภาพทางจุลชีววิทยา<br />

ขอมูลเกี่ยวกับปจจัยที่มีศักยภาพถูกรวบรวม โดยแบบสอบถามการแยกชนิดของแบคทีเรีย<br />

โดยการตรวจทางหองปฏิบัติการแบคทีเรียและการตรวจการเกิดการอับเสบของเตานมทางออมโดย<br />

น้ํายา ซี.เอ็ม.ที. ตัวอยางน้ํานมแพะที่เก็บจากเตานมจํานวน 300 ตัวอยาง และถังนมรวมจํานวน 30<br />

ตัวอยางจากฟารมแพะนมเอกชน 3 แหง ในเขตบอกอรจังหวัดชวาตะวันตกของอินโดนีเซียถูกนํามา<br />

ตรวจนับจํานวนและหาความชุกของชนิดแบคทีเรียที่ประกอบดวย TPC, coliforms,<br />

Staphylococcus spp., Coagulase Positive Staphylococci (CPS) และ Coagulase<br />

Negative Staphylococci (CNS) ทําการวิเคราะหปจจัยเสี่ยงที่มีศักยภาพ 10<br />

ปจจัยตอจํานวนและความชุกของแบคทีเรีย


ix<br />

มัธยฐานของจํานวนแบคทีเรีย TPC, coliforms, Staphylococcus spp., CPS, และ<br />

CNS ในตัวอยางน้ํานมแพะที่เก็บจากเตานมเทากับ 3.74, 0.70, 3.00, 1.70, และ 2.52 log<br />

cfu/ml ตามลํา ดับและในตัวอยางถังนมรวมเทากับ 5.69, 2.98, 3.86, 3.66, และ 3.33 log<br />

cfu/ml ตามลําดับ<br />

จํานวนเชื้อแบคทีเรียจากตัวอยางน้ํานมแพะที่เก็บจากเตานมมีความแตกตางอยางมีนัยสําคัญ<br />

ทางสถิติ (P


x<br />

TABLE OF CONTENTS<br />

Page<br />

ACKNOWLEGDEMENTS<br />

ABSTRACT IN ENGLISH<br />

ABSTRACT IN THAI<br />

LIST OF TABLES<br />

LIST OF FIGURES<br />

ABBREVIATIONS AND SYMBOLS<br />

iii<br />

vi<br />

viii<br />

xiii<br />

xv<br />

xvi<br />

1. INTRODUCTION AND OBJECTIVES 1<br />

1.1 Introduction 1<br />

1.2 Objectives 3<br />

1.3 Significance and impact <strong>of</strong> the study 4<br />

2. LITERATURE REVIEW 5<br />

2.1 The <strong>goat</strong> and its role as a <strong>milk</strong> producer in the developing<br />

countries<br />

5<br />

2.2 Microbiological characteristics <strong>of</strong> <strong>goat</strong> <strong>milk</strong> 8<br />

2.3 The pathogenic bacteria in <strong>dairy</strong> <strong>goat</strong> 11<br />

2.3.1 Prevalence <strong>of</strong> some pathogenic bacteria 11<br />

2.3.2 Udder infection in <strong>dairy</strong> <strong>goat</strong> 13<br />

2.3.3 Relationship between intramammary infections with some<br />

risk factors in <strong>dairy</strong> <strong>goat</strong><br />

15<br />

2.4 Characteristics <strong>of</strong> Staphylococcus spp 16<br />

2.4.1 Habitat and distribution 17<br />

2.4.2 Growth and requirements 18


xi<br />

Page<br />

2.5 Dairy food safety issues and public health implications 18<br />

3. MATERIALS AND METHODS 21<br />

3.1 Study design 21<br />

3.1.1 Study location 21<br />

3.1.2 Questionnaire 21<br />

3.1.3 Type <strong>of</strong> sample 21<br />

3.1.4 Bacterial indicators and laboratory <strong>investigation</strong> standard 22<br />

procedures<br />

3.2 Sample size determination 22<br />

3.3 Sampling strategy 22<br />

3.4 Laboratory procedures 23<br />

3.4.1 Total Plate Count (TPC) isolation and enumeration 23<br />

3.4.2 Total coliforms isolation and enumeration 24<br />

3.4.3 Isolation and identification <strong>of</strong> coagulase negative and positive<br />

staphylococci (Staphylococcus spp.)<br />

26<br />

3.4.4 California Mastitis Test (CMT) 29<br />

3.5 Information regarding potential risk factors <strong>from</strong> questionnaire 29<br />

survey<br />

3.6 Data management and statistical analysis 30<br />

4. RESULTS 31<br />

4.1 Results <strong>of</strong> bacterial isolation and enumeration 31<br />

4.1.1 Results <strong>from</strong> individual udder-half <strong>milk</strong> samples 31<br />

4.1.2 Results <strong>from</strong> bulk <strong>milk</strong> samples 52<br />

4.2 The comparison <strong>of</strong> indicator bacterial counts and prevalence 56


xii<br />

Page<br />

between left and right udder <strong>milk</strong> samples<br />

4.3 The comparison between California mastitis test results and<br />

conventional bacteriological isolation<br />

57<br />

5. DISCUSSION AND CONCLUSIONS 60<br />

5.1 Discussion 60<br />

5.1.1 Quantitative data 60<br />

5.1.1.1 Indicator bacterial counts <strong>of</strong> udder-half <strong>milk</strong><br />

samples among levels <strong>of</strong> some factors<br />

63<br />

5.1.2 Qualitative data 64<br />

5.1.2.1 The assessment <strong>of</strong> associations between sample<br />

prevalence <strong>of</strong> indicator bacteria with potential risk factors<br />

66<br />

5.1.3 California Mastitis Test results 69<br />

5.2 Conclusions 72<br />

REFERENCES 75<br />

APPENDIXES 82<br />

Appendix A 82<br />

Appendix B 91<br />

Appendix C 92<br />

Declaration 95<br />

SIGNED DECLARATION SHEET 95<br />

CURRICULUM VITAE 96


xiii<br />

LIST OF TABLES<br />

Table<br />

1. The twenty highest producing countries <strong>of</strong> <strong>goat</strong> <strong>milk</strong> in the world<br />

according to the rank in 2005<br />

2. List <strong>of</strong> potential risk factors related to <strong>goat</strong>s, udder and teat<br />

condition<br />

3.<br />

Selected statistical value <strong>of</strong> indicator bacterial counts <strong>from</strong> udderhalf<br />

<strong>milk</strong> samples (n= 100/farm)<br />

4. Indicator bacterial count <strong>from</strong> udder-half <strong>milk</strong> samples among<br />

breeds <strong>of</strong> <strong>goat</strong> in each farm (n = 100/farm)<br />

5. Total Plate Count <strong>from</strong> udder-half <strong>milk</strong> samples among levels <strong>of</strong><br />

each factor (n = 300)<br />

6. Coliforms counts <strong>from</strong> udder-half <strong>milk</strong> samples among levels <strong>of</strong><br />

each factor (n = 300)<br />

7. Staphylococcus spp. count <strong>from</strong> udder-half <strong>milk</strong> samples among<br />

levels <strong>of</strong> each factor (n = 300)<br />

8. Coagulase positive staphylococci (CPS) count <strong>from</strong> udder- half<br />

<strong>milk</strong> samples among levels <strong>of</strong> each factor (n = 300)<br />

9. Coagulase negative staphylococci (CNS) count <strong>from</strong> udder- half<br />

<strong>milk</strong> samples among levels <strong>of</strong> each factor (n = 300)<br />

10. Proportion <strong>of</strong> positive samples for indicator bacteria <strong>from</strong> udder –<br />

half <strong>milk</strong> samples<br />

11. Proportion <strong>of</strong> positive samples for indicator bacteria <strong>from</strong> udderhalf<br />

<strong>milk</strong> samples among breeds <strong>of</strong> <strong>goat</strong> in each farm<br />

Page<br />

7<br />

29<br />

32<br />

37<br />

38<br />

39<br />

40<br />

41<br />

42<br />

43<br />

44


xiv<br />

Table<br />

12.<br />

Summary results <strong>of</strong> the assessment <strong>of</strong> associations between sample<br />

prevalence <strong>of</strong> coliforms with potential risk factors (univariate analysis)<br />

Page<br />

45<br />

13. Logistic regression <strong>of</strong> the risk factor associated with sample<br />

prevalence <strong>of</strong> coliforms<br />

14. Summary results <strong>of</strong> the assessment <strong>of</strong> associations between sample<br />

prevalence <strong>of</strong> Staphylococcus spp. with potential risk factors<br />

(univariate analysis)<br />

15. Logistic regression <strong>of</strong> the risk factor associated with sample<br />

prevalence <strong>of</strong> Staphylococcus spp. (multivariate analysis)<br />

16. Summary results <strong>of</strong> the assessment <strong>of</strong> associations between sample<br />

prevalence <strong>of</strong> CPS with potential risk factors (univariate analysis)<br />

17. Logistic regression <strong>of</strong> the risk factor associated with sample<br />

prevalence <strong>of</strong> CPS (multivariate analysis)<br />

18. Summary results <strong>of</strong> the assessment <strong>of</strong> associations between<br />

prevalence <strong>of</strong> CNS with potential risk factors (univariate analysis)<br />

46<br />

47<br />

48<br />

49<br />

50<br />

51<br />

19. Summary <strong>of</strong> general characteristics <strong>of</strong> sampling farms 52<br />

20. Selected statistical value <strong>of</strong> indicator bacterial counts <strong>from</strong> bulk<br />

<strong>milk</strong> samples (n=10/farm)<br />

21. Proportion <strong>of</strong> positive samples <strong>of</strong> indicator bacteria <strong>from</strong> bulk <strong>milk</strong><br />

samples (n=10/farm)<br />

22. Selected statistical value <strong>of</strong> indicator bacterial counts <strong>from</strong> left and<br />

right udder <strong>milk</strong> samples (n=150/udder half)<br />

23. Proportion <strong>of</strong> positive samples <strong>of</strong> indicator bacteria <strong>from</strong> left and<br />

right udder <strong>milk</strong> samples<br />

24. The comparison between CMT and conventional bacteriological<br />

isolation results <strong>of</strong> indicator bacteria <strong>from</strong> udder-half <strong>milk</strong> samples<br />

54<br />

55<br />

56<br />

57<br />

58


xv<br />

LIST OF FIGURES<br />

Figure<br />

1. Inoculation, incubation and interpretation steps by using 3M<br />

Petrifilm for coliforms count plate (Petrifilm, 2001)<br />

2. Flow chart for isolation and identification <strong>of</strong> coagulase positive and<br />

negative staphylococci (ISO 6888-1, 1999)<br />

Page<br />

24<br />

26<br />

3. Scoring <strong>of</strong> coagulase test reactions 28<br />

4. Box and Whisker plots <strong>of</strong> TPC in three farms compared to the<br />

maximum limit <strong>of</strong> available standards ( = SNI, =<br />

EC Directive and “Milchverordnung”). (ο) = outlier values <strong>from</strong><br />

data distribution which can be represented either as the maximum or<br />

minimum value<br />

5. Box and Whisker plots <strong>of</strong> coliforms counts in three farms compared<br />

to the maximum limit <strong>of</strong> available standards ( = SNI,<br />

33<br />

33<br />

= EC Directive and “Milchverordnung”). (*) values <strong>of</strong> data<br />

distribution, (ο) = outlier value <strong>from</strong> data distribution which is<br />

represented as the maximum value<br />

6. Box and Whisker plots <strong>of</strong> CPS counts in three farms compared to the<br />

maximum limit <strong>of</strong> S. aureus in available standards ( = SNI,<br />

= EC Dir. & “Milchverordnung”). (ο) = outlier values <strong>from</strong><br />

data distribution which can be represented as the maximum value<br />

7. Bar charts <strong>of</strong> median values <strong>of</strong> indicator bacterial counts <strong>from</strong> overall<br />

udder-half <strong>milk</strong> samples (n=300)<br />

8. Bar charts <strong>of</strong> median values <strong>of</strong> indicator bacterial counts <strong>from</strong> overall<br />

bulk <strong>milk</strong> samples (n=30)<br />

34<br />

35<br />

55


xvi<br />

ABBREVIATIONS AND SYMBOLS<br />

- Negative<br />

+ Positive<br />

a w<br />

BGBl<br />

BSN<br />

cfu<br />

CI<br />

CMT<br />

CNS<br />

CPS<br />

DGLS<br />

DOM<br />

EC<br />

EFSA<br />

et al.<br />

FAO<br />

IMI<br />

IQR<br />

ISO<br />

Log Logarithm to base 10<br />

ml<br />

Milliliter<br />

MSCC<br />

Milk somatic cell count<br />

o C<br />

OR<br />

P<br />

Water activity<br />

Bundesgesetzblatt (Federal Law Gazette)<br />

Badan Standarisasi Nasional (National Standardization<br />

Body)<br />

Colony forming unit<br />

Confidence interval<br />

California Mastitis Test<br />

Coagulase Negative Staphylococci<br />

Coagulase Positive Staphylococci<br />

Directorate General <strong>of</strong> Livestock Services<br />

Digestible organic matter<br />

European Council<br />

European Food Safety Authority<br />

et alii<br />

Food and Agricultural Organization<br />

Intramammary infection<br />

Inter quartile range<br />

International Organization for Standardization<br />

Celcius degree<br />

Odd ratio<br />

Probability<br />

S. Staphylococcus<br />

SCC<br />

Somatic cell count


xvii<br />

SEC<br />

SEE<br />

SNI<br />

TPC<br />

US FDA-BAM<br />

Staphylococcal enterotoxin C<br />

Staphylococcal enterotoxin E<br />

Standar Nasional Indonesia (Indonesian National Standard)<br />

Total plate count<br />

United States Food and Drug Administration-Bacteriological<br />

Analytical Manual


1. INTRODUCTION AND OBJECTIVES<br />

1.1 Introduction<br />

Sheep and <strong>goat</strong>s form the most important group <strong>of</strong> <strong>milk</strong> producing animals<br />

after <strong>dairy</strong> cattle in both temperate and tropical agriculture (Devendra and Coop,<br />

1982). The <strong>dairy</strong> <strong>goat</strong> industry is rapidly gaining in importance throughout the world<br />

(Boscos et al., 1996).<br />

More than any other mammalian farm animal, the <strong>goat</strong> is a main supplier <strong>of</strong><br />

<strong>dairy</strong> and meat products for rural people, especially in developing countries. As a<br />

<strong>dairy</strong> supplier, the <strong>goat</strong> can accomplish one <strong>of</strong> the three aspects <strong>of</strong> the demand for<br />

<strong>goat</strong> <strong>milk</strong>: home consumption. This demand is increasing because <strong>of</strong> the growing<br />

populations <strong>of</strong> people, and here the old saying <strong>of</strong> the “<strong>goat</strong> being the cow <strong>of</strong> the poor<br />

people” is quite fitting. The second aspect <strong>of</strong> the demand for <strong>goat</strong> <strong>milk</strong> is the special<br />

interest in <strong>goat</strong> <strong>milk</strong> products, especially cheeses and yoghurt, in many developed<br />

countries. This demand is growing because <strong>of</strong> the increasing levels <strong>of</strong> disposable<br />

incomes. The third aspect <strong>of</strong> the demand for <strong>goat</strong> <strong>milk</strong> derives <strong>from</strong> the affliction <strong>of</strong><br />

people with cow <strong>milk</strong> allergies and other gastro-intestinal ailments. This demand also<br />

is growing because <strong>of</strong> a wider awareness <strong>of</strong> problems with traditional medical<br />

treatments to such afflictions, especially in developed countries. These two latter<br />

aspects <strong>of</strong> the demand for <strong>goat</strong> <strong>milk</strong> are quite different <strong>from</strong> the “<strong>goat</strong> being the cow<br />

<strong>of</strong> the poor people”; here, <strong>goat</strong> <strong>milk</strong> is wanted or even needed by people <strong>of</strong> all income<br />

levels (Haenlein, 2004).<br />

Milk is a nutritious food for human beings, but it also serves as a good<br />

medium for the growth <strong>of</strong> many microorganisms, especially bacterial pathogens.<br />

Lactococcus, Lactobacillus, Streptococcus, Staphylococcus and Micrococcus spp. are<br />

among the common bacterial flora <strong>of</strong> fresh <strong>milk</strong> (Chye et al., 2004). The importance<br />

<strong>of</strong> various etiological agents in <strong>milk</strong>borne disease has changed dramatically over time.<br />

However, more than 90% <strong>of</strong> all reported cases <strong>of</strong> <strong>dairy</strong>-related illness continue to be


2<br />

<strong>of</strong> bacterial origin, with at least 21 <strong>milk</strong>borne or potentially <strong>milk</strong>borne diseases<br />

currently being recognized (Bean et al., 1996).<br />

Zweifel et al. (2005) stated that <strong>goat</strong>s and sheep rank third and fourth in<br />

terms <strong>of</strong> global <strong>milk</strong> production <strong>from</strong> different species. But unlike cow <strong>milk</strong>, which<br />

has stringent hygiene and quality regulations, <strong>microbiological</strong> standards for the<br />

production and distribution <strong>of</strong> <strong>goat</strong> <strong>milk</strong> and sheep <strong>milk</strong> are more relaxed (Klinger<br />

and Rosenthal, 1997).<br />

According to FAO (2006), Indonesia was ranked as the 14 th in producing <strong>goat</strong><br />

<strong>milk</strong> globally and ranked as the 1 st in the Southeast Asia region in 2005. It was<br />

estimated to produce around 220,000 metric tons (MT) <strong>of</strong> <strong>goat</strong> <strong>milk</strong>. In 2005, the <strong>goat</strong><br />

population in Indonesia was 13,182,000 head in total, out <strong>of</strong> that West Java province<br />

was ranked the 3 rd in the country with 1,235,973 head <strong>of</strong> <strong>goat</strong> (DGLS, 2005). On the<br />

one hand, unlike cow’s <strong>milk</strong>, hygiene and quality regulations for production and<br />

distribution <strong>of</strong> small ruminant’s <strong>milk</strong>, such as <strong>goat</strong> <strong>milk</strong> are more relaxed in Indonesia<br />

and are not subject to specific <strong>microbiological</strong> standards in a legal sense. So far this<br />

product has less attention in terms <strong>of</strong> quality and safety control <strong>from</strong> farmer<br />

organizations and/or government institutions than those for cow’s <strong>milk</strong> and <strong>milk</strong><br />

products. On the other hand, most <strong>of</strong> the consumers prefer to drink <strong>raw</strong> <strong>goat</strong> <strong>milk</strong> due<br />

to their belief in the benefit <strong>of</strong> <strong>raw</strong> <strong>goat</strong> <strong>milk</strong> as a health promoting agent, or even<br />

disease-relief agent.<br />

Investigation on the <strong>microbiological</strong> quality such as Total Plate Count (TPC),<br />

coliforms and the presence <strong>of</strong> pathogenic bacteria <strong>of</strong> <strong>goat</strong> <strong>milk</strong> together with some<br />

risk factors affecting these microorganisms in Indonesia was very rare. In view <strong>of</strong><br />

food hygiene and consumer health as well as animal health protection, however,<br />

evaluation <strong>of</strong> the <strong>microbiological</strong> status and presence <strong>of</strong> pathogenic bacteria in <strong>goat</strong><br />

<strong>milk</strong>, which can cause adverse health effects on the animals as well as pose a high risk<br />

<strong>of</strong> causing foodborne disease in humans, is <strong>of</strong> central importance.<br />

The presence <strong>of</strong> microorganisms in <strong>milk</strong> and <strong>milk</strong> products has important<br />

ramifications for safety, quality, regulations and public health. TPC is the first and


3<br />

principal tool used by technicians and farmers to evaluate the efficiency <strong>of</strong> production<br />

processes, cleaning and sanitation practices and to predict the keeping quality and<br />

shelf life <strong>of</strong> <strong>milk</strong> (Gonzalo et al., 2006). Jayarao and Wang (1999) stated that <strong>milk</strong><br />

<strong>from</strong> the farm can become contaminated with Gram negative bacteria present on teats,<br />

the teat ends, teat canal, udder surfaces, mastitic udders and contaminated water used<br />

to clean the <strong>milk</strong>ing systems and those that are resident in the <strong>milk</strong>ing system. Gram<br />

negative organisms associated with <strong>milk</strong> quality can be placed into two groups,<br />

coliforms and non coliforms. Both groups are responsible in lowering <strong>milk</strong> quality<br />

and have significant concern on public health importance (Jayarao and Wang, 1999).<br />

Staphylococcus spp. are the main aetiological agents <strong>of</strong> small ruminant’s<br />

intramammary infections (IMI), the more frequent isolates being Staphylococcus<br />

aureus (coagulase-positive staphylococci [CPS]) in clinical cases and coagulasenegative<br />

staphylococci (CNS) in subclinical IMI (Bergonier et al., 2003).<br />

Staphylococcus spp. can be found widely distributed in animals, and it is a contagious<br />

pathogen that can be transmitted <strong>from</strong> doe to doe during unhygienic <strong>milk</strong>ing<br />

procedures. High prevalence <strong>of</strong> CPS such as S. aureus, or CNS can be <strong>of</strong> veterinary<br />

public health concern. Both groups <strong>of</strong> bacteria are important zoonotic bacterial<br />

pathogens, which can also be transmitted to humans through <strong>goat</strong>s’ <strong>raw</strong> <strong>milk</strong> and<br />

cause food poisoning associated with enterotoxin production (Wakwoya et al., 2006).<br />

1.2 Objectives<br />

The objectives <strong>of</strong> this study were (i) to investigate the <strong>microbiological</strong> quality<br />

<strong>of</strong> <strong>raw</strong> <strong>goat</strong> <strong>milk</strong> by using TPC and coliforms as indicators (ii) to investigate the<br />

presence <strong>of</strong> Staphylococcus spp. (coagulase positive and negative staphylococci) in<br />

<strong>raw</strong> <strong>goat</strong> <strong>milk</strong>, and (iii) to evaluate the potential risk factors associated with them in<br />

<strong>dairy</strong> <strong>goat</strong> farms in the Bogor District, West Java Province, Indonesia.


4<br />

1.3 Significance and impact <strong>of</strong> the study<br />

It was expected that the result <strong>of</strong> this study would provide a primary scientific<br />

database for the <strong>microbiological</strong> quality <strong>of</strong> <strong>raw</strong> <strong>goat</strong> <strong>milk</strong> in Indonesia, and some<br />

potential risk factors associated with it. Moreover, the baseline information <strong>from</strong> this<br />

research could be used by the related stakeholders in formulating intervention<br />

programs for assisting the farmers to improve their systems in keeping animals and<br />

the quality and safety <strong>of</strong> their product, as well as in designing further studies aimed in<br />

setting up preventive measures against the introduction <strong>of</strong> pathogenic agents into the<br />

animal and its product.


2. LITERATURE REVIEW<br />

2.1 The <strong>goat</strong> and its role as a <strong>milk</strong> producer in the developing countries<br />

World production <strong>of</strong> <strong>milk</strong> is forecast to rise to 665 million tons by 2010,<br />

representing an average annual increase <strong>of</strong> 1.5 percent, compared to an annual<br />

average growth rate <strong>of</strong> 1.0 percent during the 1990s. Milk production is projected to<br />

grow in each <strong>of</strong> the major country groupings (developed, transitional and developing);<br />

however, the largest increment is expected in the developing countries. In these<br />

countries, the output <strong>of</strong> <strong>milk</strong> is projected to rise by 71 million tons to reach 293<br />

million tons. As a consequence, the share <strong>of</strong> developing countries in world <strong>milk</strong><br />

production is expected to rise to 44 percent (against 39 percent in the base period and<br />

32 percent at the start <strong>of</strong> the 1990s). Conversely, while production in the developed<br />

countries and that in transition economies is projected to rise, the relative share <strong>of</strong><br />

world <strong>milk</strong> production is expected to decrease in both groups (FAO, 2002).<br />

FAO (2002) also stated that the strongest growth in demand for <strong>milk</strong> and <strong>milk</strong><br />

products is anticipated to come <strong>from</strong> the developing countries, where it is projected to<br />

grow at the rate <strong>of</strong> 2.5 percent per year, broadly comparable with the growth rate<br />

during the 1990s. For the countries in transition, little growth (0.9 percent per year)<br />

over the 1999 benchmark is projected; however, this would be a substantial<br />

improvement over the 1990s, when consumption dropped at an average annual rate <strong>of</strong><br />

3.3 percent in this group <strong>of</strong> countries. In the developed countries, consumption <strong>of</strong><br />

<strong>milk</strong> and <strong>milk</strong> products is also expected to show only limited growth (0.5 percent per<br />

year - a similar level to that experienced during the 1990s). Amongst the developing<br />

countries, as was the case in the 1990s, consumption <strong>of</strong> <strong>milk</strong> and <strong>milk</strong> products is<br />

expected to grow most strongly in Asia, which is projected to account for almost 52<br />

percent <strong>of</strong> the growth in world demand. Significant growth in demand, 18 million<br />

tons, or 18 percent <strong>of</strong> the projected rise in the world total, is also expected in the Latin<br />

America and Caribbean region. Within this region, Brazil and Mexico are anticipated<br />

to see the largest increases in consumption. Africa is expected to register the smallest


6<br />

increase in demand amongst the developing country regions, as was the case in the<br />

1990s, and in many countries in this region this will represent a growth rate slower<br />

than that for the population.<br />

Knights and Garcia (1997) reported that in the ‘developing’ tropics where<br />

there are about 95% <strong>of</strong> the total world’s <strong>goat</strong> populations, this increase demand <strong>of</strong><br />

<strong>milk</strong> and <strong>milk</strong> products could be best made up <strong>from</strong> <strong>goat</strong> <strong>milk</strong>. The <strong>goat</strong> is well<br />

adapted to the tropics; has short generation intervals, high fertility, prolificacy and<br />

fecundity; has high heritability for <strong>milk</strong> production (0.5); has superior digestive<br />

efficiency over <strong>dairy</strong> cattle when fed low quality forages (kg <strong>milk</strong> yield/100 kg DOM<br />

<strong>of</strong> 67.1 to 145; 86 to 101.5; 73.6 and 71.1 to 91.1 for <strong>goat</strong>s, <strong>dairy</strong> cattle, <strong>dairy</strong> buffalo<br />

and sheep, respectively) and is a more efficient <strong>milk</strong> producer under tropical<br />

conditions (kg <strong>milk</strong> yield/kg live weight <strong>of</strong> 2.8 to 7.1, 2.4 to 3.4, and 4.0 for <strong>goat</strong>s,<br />

<strong>dairy</strong> cattle and <strong>dairy</strong> buffalo, respectively). Goat <strong>milk</strong>, owing to its composition, has<br />

a potentially greater role to play in future human nutrition and medicine than <strong>milk</strong><br />

<strong>from</strong> cattle. Goat farmers would more readily set up or expand <strong>goat</strong> enterprises<br />

because <strong>of</strong> the lower capital investments required concurrent with lower risks.<br />

This was also supported by the data <strong>from</strong> FAO (2006) for the 20 highest<br />

producing countries <strong>of</strong> <strong>goat</strong> <strong>milk</strong> in the world in 2005 (Table 1), which mostly comes<br />

<strong>from</strong> developing countries and particularly <strong>from</strong> the tropical area.<br />

According to Galal (2005), developing countries harbour 96% <strong>of</strong> the world<br />

<strong>goat</strong> population, but only 60% <strong>of</strong> the breeds. Europe has the heaviest <strong>goat</strong> breeds<br />

with the largest litter size and <strong>milk</strong> production, while Latin America and the<br />

Caribbean scored lowest in all these performance traits. Breed variability was lowest<br />

in Europe and highest in Africa. Many <strong>goat</strong> breeds are not characterized because most<br />

<strong>goat</strong>s and breeds are in developing countries, and/or under extensive production<br />

systems where characterization becomes more demanding.


7<br />

Table 1: The twenty highest producing countries <strong>of</strong> <strong>goat</strong> <strong>milk</strong> in the world according<br />

to the rank in 2005<br />

Rank<br />

Country<br />

Production<br />

(Metric Tones)<br />

Remark<br />

1. India 2,700,000 *<br />

2. Bangladesh 1,416,000 F<br />

3. Sudan 1,295,000 F<br />

4. Pakistan 660,000<br />

5. France 587,000<br />

6. Greece 495,000 F<br />

7. Spain 465,000 F<br />

8. Iran, Islamic Rep. 365,000 F<br />

9. Ukraine 290,000 *<br />

10. Russian Federation 259,000 *<br />

11. China 256,000 F<br />

12. Turkey 240,000 F<br />

13. Mali 238,590 F<br />

14. Indonesia 220,000 F<br />

15. Algeria 160,000 F<br />

16. Mexico 154,478 F<br />

17. Brazil 135,000 F<br />

18. Italy 115,000 F<br />

19. Mauritania 109,800 F<br />

20. Bulgaria 109,320<br />

Source: (FAO, 2006)<br />

Remark:<br />

* = Un<strong>of</strong>ficial figure<br />

No symbol = Official figure<br />

F = FAO estimate<br />

The European Union (EU) has 1.5% (11,730,164 head in the year 2002) <strong>of</strong> the<br />

world <strong>goat</strong> population. Four countries (Italy, Greece, Spain and France) in the<br />

Mediterranean area account for 91% <strong>of</strong> the EU <strong>goat</strong> population and 95% <strong>of</strong> its <strong>goat</strong><br />

<strong>milk</strong> production (Moroni et al., 2005b).


8<br />

2.2 Microbiological characteristics <strong>of</strong> <strong>goat</strong> <strong>milk</strong><br />

According to compositional differences between the <strong>milk</strong> <strong>from</strong> cows, <strong>goat</strong>s<br />

and sheep, the quality standards for the <strong>milk</strong> <strong>from</strong> small ruminant animals should be<br />

adjusted and evaluated based on the individual <strong>milk</strong> source (Morgan et al., 2003;<br />

Zweifel et al., 2005). The European Council (EC) (1992), in European Council<br />

Directive 92/46/EEC, stated that the TPC and S. aureus <strong>of</strong> small ruminant’s <strong>raw</strong> <strong>milk</strong><br />

used for the manufacture <strong>of</strong> <strong>raw</strong>-<strong>milk</strong> products must not exceed 5.7 and 3.3 log<br />

cfu/ml, respectively. Those maximum limit standards were similar to <strong>milk</strong> regulation<br />

(Milchverordnung) in Germany which was last amended in 2004 for products ‘made<br />

with <strong>raw</strong> sheep or <strong>goat</strong> <strong>milk</strong>’. There was no specific standard for coliforms count<br />

within this category, but there was a separate category <strong>of</strong> <strong>milk</strong> called “Vorzugsmilch”<br />

which was certified for consumption as <strong>raw</strong> <strong>milk</strong>. This <strong>milk</strong>, which was referred to<br />

as “certified Grade A <strong>milk</strong>,” could be sold <strong>commercial</strong>ly as a retail product. The<br />

number <strong>of</strong> coliforms in “Vorzugsmilch” must not exceed 2 log cfu/ml (BGBl Teil I<br />

Nr. 58 S 2794, 2004). In Indonesia, there was not any specific legal standard for<br />

fresh/<strong>raw</strong> <strong>goat</strong> <strong>milk</strong> but there was a standard <strong>from</strong> Indonesian National Standard for<br />

fresh <strong>milk</strong> (SNI 01-3141-1998) designed, based on cow <strong>milk</strong>. According to the<br />

standard, TPC <strong>of</strong> fresh <strong>milk</strong> must not exceed 6.0 log cfu/ml, 1.3 log cfu/ml for<br />

coliforms and 2 log cfu/ml for S. aureus (BSN, 1998).<br />

Difficulties in managing the sanitary quality <strong>of</strong> sheep and <strong>goat</strong> <strong>milk</strong> derive<br />

<strong>from</strong> a series <strong>of</strong> factors including the low level <strong>of</strong> production per head, the <strong>milk</strong>ing<br />

system, the difficulty involved in machine <strong>milk</strong>ing, the conditions under which the<br />

herds or flocks are raised, adverse climatic conditions and the spread <strong>of</strong> production<br />

over a wide geographic area (Klinger and Rosenthal, 1997).<br />

The prerequisite to produce hygienic <strong>milk</strong> and cheese is udder health;<br />

therefore, intramammary infections (IMI) are <strong>of</strong> great importance to <strong>milk</strong> hygiene in<br />

<strong>dairy</strong> <strong>goat</strong>s (Moroni et al., 2005b). Mastitis is one <strong>of</strong> the most costly diseases in the<br />

<strong>dairy</strong> industry, and, although much information is available concerning mastitis in<br />

cows, few studies deal with mastitis in <strong>goat</strong>s. Researchers studying subclinical<br />

mastitis in <strong>goat</strong>s agree that IMI caused by coagulase-negative staphylococci (CNS)


9<br />

are the most prevalent. Despite the high prevalence <strong>of</strong> IMI caused by CNS, CNS were<br />

considered to be minor pathogens. However, IMI caused by CNS was associated with<br />

clinical mastitis, changes in <strong>milk</strong> composition and reduced <strong>milk</strong> yield; IMI caused by<br />

CNS was also capable <strong>of</strong> persisting throughout lactation and the dry period (Contreras<br />

et al., 1997).<br />

Reports regarding factors affecting small ruminant’s <strong>milk</strong> quality mainly deal<br />

with <strong>milk</strong> composition as a chemical composition <strong>of</strong> lipids, phosphatase level,<br />

freezing point, natural bacterial inhibitor levels and especially the parameter Somatic<br />

Cell Count (SCC) (Haenlein, 2002; Sevi et al., 2004). The relationship <strong>of</strong> SCC to the<br />

<strong>microbiological</strong> quality <strong>of</strong> small ruminant’s <strong>milk</strong> and its expressiveness remains<br />

controversial (Zeng and Escobar, 1995). SCC seems to be always influenced by<br />

various factors such as stage <strong>of</strong> lactation, oestrus, parity, time <strong>of</strong> sampling (before,<br />

during or after <strong>milk</strong>ing), stress and lambing season (Haenlein, 2002; Sevi et al.,<br />

2004). Several authors did not reveal positive interactions <strong>of</strong> SCC with the presence<br />

<strong>of</strong> bacterial infection or target <strong>of</strong> microbial tested (Foschino et al., 2002; Delgado-<br />

Pertinez et al. 2003, Kyozaire et al., 2005).<br />

Moreover the panel on biological hazards <strong>of</strong> European Food Safety<br />

Authority (EFSA) (2005) has made an opinion on the usefulness <strong>of</strong> somatic cell<br />

counts for the safety <strong>of</strong> <strong>milk</strong> and <strong>milk</strong>-derived products <strong>from</strong> <strong>goat</strong>s. The panel<br />

concluded that due to the high variability <strong>of</strong> SCC in <strong>goat</strong> <strong>milk</strong>, even in healthy<br />

animals, SCC cannot be relied on either as a specific indicator for TSE (Transmissible<br />

Spongiform Encephalopathy) risk, nor as an indicator <strong>of</strong> udder health. Three main<br />

types <strong>of</strong> difficulties were noted in the EFSA review:<br />

• The count accuracy is affected by the apocrine nature <strong>of</strong> <strong>milk</strong> secretion in<br />

<strong>goat</strong>s. Cytoplasmic particles, which derive <strong>from</strong> the apical part <strong>of</strong> secretory<br />

cells, are normal constituents in <strong>goat</strong> <strong>milk</strong>. Certain methods used to count<br />

somatic cells cannot distinguish these cytoplasmic particles, similar in size<br />

to somatic cells, <strong>from</strong> real somatic cells, which may lead to false readings.<br />

Moreover, the reference microscopy method, which is based on staining


10<br />

procedures, does not give satisfactory results in the majority <strong>of</strong> laboratories,<br />

when used on <strong>goat</strong> <strong>milk</strong>.<br />

• Somatic cells that are identified in <strong>milk</strong> <strong>from</strong> healthy cows or ewes are<br />

mainly macrophages. Less than 30% are other leukocytes. Higher levels <strong>of</strong><br />

the latter are considered to be indicative <strong>of</strong> inflammation. On the other hand,<br />

leukocytes can reach up to 60% <strong>of</strong> total cells in normal <strong>goat</strong> <strong>milk</strong>. The<br />

somatic cell count is therefore difficult to interpret in terms <strong>of</strong> udder<br />

inflammation.<br />

• Non-infectious factors greatly influence the somatic cell count in <strong>goat</strong>s.<br />

Physiological normality is dependent on the stage <strong>of</strong> lactation, age, time <strong>of</strong><br />

sampling, the oestrus period, feed, stress, breed and the region. Most experts<br />

in this field therefore consider that a specific somatic cell count-value<br />

derived <strong>from</strong> one population <strong>of</strong> <strong>goat</strong>s may describe a normal animal health<br />

status in a second population, and indicate mastitis in a third population.<br />

Most <strong>of</strong> the reports concerning the <strong>microbiological</strong> characteristics <strong>of</strong> <strong>goat</strong> <strong>milk</strong><br />

were dealt only with <strong>investigation</strong> on the prevalence <strong>of</strong> target pathogenic organisms,<br />

SCC and microbial quality <strong>of</strong> the <strong>milk</strong> (Deinh<strong>of</strong>er and Pernthaner, 1995; Contreras et<br />

al., 1999; Abou-Eleinin et al., 2000; Ndegwa et al., 2001; McDougall et al., 2002;<br />

Foschino et al., 2002; Contreras et al., 2003; Wakwoya et al., 2006; Leitner et al.,<br />

2007; Hall and Rycr<strong>of</strong>t, 2007).<br />

Whereas reports on the evaluation <strong>of</strong> different factors concerning farm<br />

management and <strong>milk</strong>ing practices as well as other predisposing factors <strong>from</strong> <strong>goat</strong><br />

condition in association with microbial quality and the prevalence <strong>of</strong> pathogenic<br />

bacteria in <strong>goat</strong> <strong>milk</strong> were very limited (Zeng and Escobar, 1995; Zeng and Escobar,<br />

1996; Peris et al., 1999; Sanchez et al., 1999; Ameh and Tari, 2000; Zweifel et al.,<br />

2005; Kyozaire et al., 2005).<br />

Zweifel et al. (2005) reported that <strong>from</strong> 344 samples <strong>of</strong> bulk-tank <strong>goat</strong> <strong>milk</strong>,<br />

the median for Standard Plate Count (SPC) or Total Bacterial Count (TBC) was 4.69


11<br />

log colony forming units (cfu)/ml. They concluded that farms with a flock size >25<br />

animals, sampled in June, using mechanized <strong>milk</strong>ing systems (especially bucket<br />

<strong>milk</strong>ing without parlor) as well as farms with <strong>milk</strong> delivery every second or third day,<br />

showed significantly higher SPC levels, whereas the highest probability <strong>of</strong> a low SPC<br />

result was observed during July, in farms with a flock size


12<br />

Foschino et al. (2002) reported that E. coli O157:H7 was found in 1.7% <strong>of</strong><br />

<strong>goat</strong> <strong>milk</strong> samples collected <strong>from</strong> ten farms in the Bergamo area, Italy. S. aureus was<br />

found in 43% <strong>of</strong> samples, whereas CNS were found in 90% <strong>of</strong> samples, including<br />

Staphylococcus caprae as the coagulase negative species that was the most frequently<br />

isolated.<br />

McDougall et al. (2001) also reported that hygienically, <strong>goat</strong> <strong>milk</strong> production<br />

conditions in Greece and Portugal, under extensive breeding systems had: total<br />

bacteria <strong>of</strong> 3.6×10 7 and 4×10 7 cfu/ml; coliforms <strong>of</strong> 1.8×10 6 and 2.5×10 6 cfu/ml;<br />

staphylococci coagulase positive and negative <strong>of</strong> 1.7 × 10 5 and 7.6 × 10 4 cfu/ml, for<br />

Greece and Portugal respectively. For France, using intensive breeding systems, the<br />

<strong>microbiological</strong> quality <strong>of</strong> the <strong>goat</strong> <strong>milk</strong> was: total bacteria 1.08×10 5 cfu/ml; coliforms<br />

1.40×10 2 cfu/ml and staphylococci coagulase positive and negative 2.75 × 10 2 cfu/ml.<br />

Moroni et al. (2005b) reported that among 305 <strong>goat</strong>s with IMI, 52.3% had<br />

unilateral infection, whereas the others had both udder halves infected. Among the<br />

bilateral infections, 87% were caused by CNS versus 5% for Staphylococcus aureus<br />

and environmental bacteria and 3% by Streptococci. The prevalence <strong>of</strong> IMI in the left<br />

and right half udders were similar with 40.4% and 40.0%, respectively.<br />

Kyozaire et al. (2005) reported that <strong>from</strong> 270 udder halves, <strong>milk</strong> samples<br />

collected <strong>from</strong> <strong>dairy</strong> <strong>goat</strong> farms with different production systems were infected with<br />

bacteria in 31.1% <strong>of</strong> the samples. The lowest IMI was found amongst <strong>goat</strong>s in the<br />

herd under the extensive system (13.3%) compared with 43.3% and 36.7% infection<br />

rates under the intensive and semi-intensive production systems, respectively.<br />

Staphylococcus intermedius (coagulase positive), Staphylococcus epidermidis and<br />

Staphylococcus simulans (both coagulase negative) were the most common cause <strong>of</strong><br />

IMI with a prevalence <strong>of</strong> 85.7% <strong>of</strong> the infected udder halves. The remaining 14.3% <strong>of</strong><br />

the infection was due to Staphylococcus aureus.<br />

In another study conducted by Leitner et al. (2007), they found that <strong>of</strong> the 754<br />

udder halves <strong>from</strong> 377 <strong>goat</strong>s tested, 28.8% were infected with various Staphylococcus


13<br />

species i.e. S. aureus, 9.6%; S. chromogenes, 3.3%; S. epidermidis, 5.9%; S. simulans,<br />

5.5% and S. caprae, 3.3% or Corynebacteria spp., 1.5%.<br />

Whereas Hall and Rycr<strong>of</strong>t (2007) reported that an IMI was found in 53<br />

(33%) <strong>of</strong> the <strong>goat</strong>’s udder halves; the prevalence was 26 per cent on farm A, 39% on<br />

farm C and 42% on farm B. CNS were the most common group <strong>of</strong> organisms,<br />

affecting 47 per cent <strong>of</strong> the infected halves. The number <strong>of</strong> bacteria in the <strong>milk</strong> ranged<br />

<strong>from</strong> 1 x 10 3 to 1.2 x 10 5 cfu/ml. S. aureus was found in seven <strong>of</strong> the samples (13 per<br />

cent), most <strong>of</strong> which yielded between 1 x 10 4 and 3 x 10 4 cfu/ml; the highest yielded<br />

(maximum value) was 1.8 x 10 5 cfu/ml. Corynebacterium species were present in 16<br />

(31%) <strong>of</strong> the positive samples and α-haemolytic streptococci were present in three<br />

(6%) <strong>of</strong> them.<br />

2.3.2 Udder infection in <strong>dairy</strong> <strong>goat</strong>s<br />

Mastitis in sheep and <strong>goat</strong>s is predominantly subclinical (Contreras et al.,<br />

1999). CNS are the most prevalent pathogens causing subclinical mastitis in <strong>dairy</strong><br />

ruminants. Although less pathogenic than S. aureus, CNS can also produce persistent<br />

subclinical mastitis, significant increase in <strong>milk</strong> somatic cell count (MSCC), cause<br />

clinical mastitis (Deinh<strong>of</strong>er and Pernthaner, 1995; Ariznabarreta et al., 2002), as well<br />

as produce thermostable enterotoxins (Meyrand et al., 1999). Nevertheless, despite<br />

the accepted role <strong>of</strong> these bacteria as major IMI-causing pathogens in small<br />

ruminants, the pathogenicity <strong>of</strong> the different CNS species varies widely (Contreras et<br />

al., 2007). The most commonly isolated CNS species in persistent subclinical IMI in<br />

<strong>goat</strong>s and sheep are Staphylococcus epidermidis, Staphylococcus caprae,<br />

Staphylococcus simulans, Staphylococcus chromogenes and Staphylococcus xylosus<br />

(Contreras et al., 2003; Bergonier et al., 2003).<br />

CNS are the most prevalent organisms detectable on udder skin, inside the<br />

streak canal and in mammary glands <strong>of</strong> <strong>dairy</strong> <strong>goat</strong>s and sheep. Various CNS species<br />

are commonly detected in <strong>goat</strong> <strong>milk</strong> and these microorganisms can frequently cause<br />

subclinical infections persisting for several months, even through the dry period<br />

(Moroni et al., 2005a). In caprine intramammary infection, the CNS are the most


14<br />

prevalent microorganisms (ranging <strong>from</strong> 25 to 93% <strong>of</strong> IMI, depending on the study),<br />

and are isolated mainly <strong>from</strong> chronic and subclinical infections (Bergonier et al.,<br />

2003).<br />

CNS are contagious pathogens found on the skin <strong>of</strong> <strong>goat</strong>s and human hands<br />

and can easily be transmitted during unhygienic <strong>milk</strong>ing procedures (Kalogridou-<br />

Vassiliadou, 1991). Among the CNS, Staphylococcus caprae is the most prevalent<br />

species, followed by S. epidermidis, S. xylosus, S. chromogenes, and S. simulans<br />

(Contreras et al., 1999). Although many <strong>of</strong> the coagulase negative species noted adapt<br />

primarily to non-human hosts, their entry into human foods is not precluded. Once in<br />

susceptible foods, their growth may be expected to lead to the production <strong>of</strong><br />

enterotoxin which can cause staphylococcal food poisoning or food intoxication (Jay<br />

et al., 2005).<br />

S. epidermidis and S. caprae are among the most prevalent causal<br />

microorganisms in <strong>goat</strong>s and S. epidermidis and S. simulans are in ewes. The presence<br />

<strong>of</strong> different CNS species could be attributable to certain practices for controlling<br />

mastitis, such as the protocol and type <strong>of</strong> disinfectant used for teat dipping or dry-<strong>of</strong>f<br />

treatments (Contreras et al., 2003). Because novobiocin-sensitive CNS seem to be the<br />

most pathogenic, we should consider including this antibiotic in the dry-<strong>of</strong>f treatment<br />

procedure (Deinh<strong>of</strong>er and Pernthaner, 1995), although maximum residue limits for<br />

sheep and <strong>goat</strong> <strong>milk</strong> have not yet been defined for this antibiotic (Contreras et al.,<br />

2007).<br />

Microbiological quality <strong>of</strong> <strong>goat</strong>’s <strong>milk</strong> obtained under different production<br />

systems in South Africa was investigated by Kyozaire et al. (2005). They reported<br />

that Staphylococcus intermedius (coagulase positive), S. epidermidis and S. simulans<br />

(both coagulase negatives) were the most common cause <strong>of</strong> IMI with a prevalence <strong>of</strong><br />

85.7% <strong>of</strong> the infected udder halves, the remaining 14.3% <strong>of</strong> the infection was due to<br />

S. aureus. Wakwoya et al. (2006) reported that the main bacterial pathogens isolated<br />

<strong>from</strong> <strong>goat</strong> <strong>milk</strong> samples were S. aureus (12.8%), Bacillus spp. (13.8%),<br />

Corynebacterium (10.9%) and CNS (9.6%). Other bacteria that were also detected<br />

included Streptococcus agalactiae, Streptococcus dysagalactiae, Klebsiella


15<br />

pneumoniae, Enterobacter aerogenes, Escherichia coli, Pasteurella (Mannheimia)<br />

haemolytica and Micrococcus spp.<br />

S. aureus is the most important mastitic pathogen in most herds. Symptoms<br />

vary <strong>from</strong> acute clinical to subclinical mastitis. In particularly severe cases the<br />

infection may progress to gangrene. It is characterized by the presence <strong>of</strong> a watery,<br />

dark red secretion which may be accompanied by gas bubbles resulting <strong>from</strong><br />

secondary infection with gas forming organisms (particularly Clostridium spp). Death<br />

may be immediate or occur after several days. Some animals will recover and<br />

eventually slough away the necrotic tissue (Shearer and Harris, 2003).<br />

2.3.3 Relationship between intramammary infections with some risk factors in <strong>dairy</strong><br />

<strong>goat</strong>s<br />

Studies have been conducted to investigate the relationship between IMI and<br />

some risk factors associated with it in <strong>dairy</strong> <strong>goat</strong>s to find out the effective way in<br />

preventing mastitis at the farm level. Zeng and Escobar (1996) evaluated the effect <strong>of</strong><br />

breeds and <strong>milk</strong>ing methods on SCC, standard plate count and <strong>goat</strong> <strong>milk</strong> composition,<br />

whereas Boscos et al. (1996) studied the prevalence <strong>of</strong> subclinical mastitis and the<br />

influence <strong>of</strong> breed, parity, stage <strong>of</strong> lactation and mammary bacteriological status with<br />

the California Mastitis Test (CMT), Coulter Colony Count (CCC), in <strong>dairy</strong> <strong>goat</strong>s. The<br />

relationship between CMT and SCC in <strong>dairy</strong> <strong>goat</strong>s was investigated by Perrin et al.<br />

(1997). Winter and Baumgartner (1999) stated, based on their study results, that<br />

CMT can be used as an additional diagnostic tool concerning <strong>goat</strong> mastitis.<br />

McDougall et al. (2001) have studied the relationship among SCC, CMT,<br />

impedance and the bacteriological status <strong>of</strong> <strong>milk</strong> with lactation stages in <strong>goat</strong>s and<br />

sheep. Shearer and Harris (2003) also stated that the CMT score can be used as a tool<br />

for indicating the mastitis status in <strong>dairy</strong> <strong>goat</strong>s. The CMT reagent reacts with genetic<br />

material <strong>of</strong> somatic cells present in <strong>milk</strong> to form a gel. In general <strong>milk</strong> samples <strong>from</strong><br />

non-infected glands will yield a negative (0), trace, or +1 reaction, score <strong>of</strong> +2 or +3<br />

are indicative <strong>of</strong> mastitis.


16<br />

2.4 Characteristics <strong>of</strong> Staphylococcus spp.<br />

The staphylococci were first described by the Scottish surgeon, Sir Alexander<br />

Ogston as the cause <strong>of</strong> a number <strong>of</strong> pyogenic (pus forming) infections in humans. In<br />

1882, he gave them the name Staphylococcus (Greek: staphyle, bunch <strong>of</strong> grapes;<br />

coccus, a grain or berry), after their appearance under the microscope (Adams and<br />

Moss, 2000).<br />

The genus Staphylococcus includes over 30 species and those <strong>of</strong> real and<br />

potential interest in foods are about 18 species, out <strong>of</strong> them only 6 species are<br />

coagulase positive (S. aureus, S. aureus subsp. anaerobius, S. intermedius, S. hyicus,<br />

S. delphini and S. schleiferi subsp. coagulans). These coagulase positive<br />

staphylococci group bacteria generally produce thermostable nuclease (TNase).<br />

Among the coagulase positive species, S. intermedius is well known as an enterotoxin<br />

producer. Ten <strong>of</strong> the coagulase negative species have been shown to produce<br />

enterotoxins, but they do not produce nuclease, or those that do produce a<br />

thermolabile form. The coagulase negative enterotoxigenic strains are not consistent<br />

in their production <strong>of</strong> hemolysins or their fermentation <strong>of</strong> mannitol (Jay et al., 2005).<br />

Valle et al. (1990) reported that 22% <strong>of</strong> the 272 CNS isolates originated <strong>from</strong><br />

healthy <strong>goat</strong>s were enterotoxin positive, and staphylococcal enterotoxin C (SEC) was<br />

the most frequently found enterotoxin among the <strong>goat</strong> isolates. Seven species <strong>of</strong> the<br />

<strong>goat</strong> isolates produced more than one enterotoxin (S. caprae, S. epidermidis, S.<br />

haemolyticus, S. saprophyticus, S. sciuri, S. warneri and S. xylosus) and two species<br />

produced only one, SEC by S. chromogens and staphylococcal enterotoxin E (SEE)<br />

by S. lentus (Valle et al.,1990).<br />

Contreras et al. (2007) stated that rather than be a risk for human health that<br />

could be caused by some mastitis-causing bacteria, <strong>milk</strong> is generally heat-treated to<br />

minimize this effect. However, in regions where cheese is made <strong>from</strong> <strong>raw</strong> <strong>milk</strong>,<br />

controlling clinical and subclinical mastitis becomes a priority. Even when using<br />

pasteurized <strong>milk</strong>, the ability <strong>of</strong> some bacteria, such as Staphylococcus aureus, to<br />

produce thermostable toxins, enhances the zoonotic role <strong>of</strong> these pathogens. Under


17<br />

European legislation, the control <strong>of</strong> S. aureus is mandatory, such that the marketing <strong>of</strong><br />

sheep, <strong>goat</strong> and cow <strong>milk</strong> containing S. aureus is highly restricted (Directive<br />

92/46ECC Council, 1992).<br />

2.4.1 Habitat and distribution<br />

According to Jay et al. (2005), the staphylococcal species are host-adapted<br />

with about one-half <strong>of</strong> the known species inhabiting humans solely (e.g.,<br />

Staphylococcus cohnii subsp. cohnii) or humans and other animals (e.g., S. aureus).<br />

The largest numbers tend to be found near openings to the body surface such as the<br />

anterior nares, axillae, and the inguinal and perineal areas where in moist habitats,<br />

numbers per square centimeter may reach 10 3 – 10 6 , and in dry habitats, 10 - 10 3 . The<br />

two most important sources to foods are nasal carriers and individuals whose hands<br />

and arms are inflicted with boils and carbuncles, who are permitted to handle food.<br />

Most domesticated animals harbor S. aureus. Staphylococcal mastitis is not<br />

unknown among <strong>dairy</strong> herds, and if <strong>milk</strong> <strong>from</strong> infected cows is consumed or used for<br />

cheese making, the chances <strong>of</strong> contracting food intoxication are excellent. There is<br />

little doubt that many strains <strong>of</strong> this organism that cause bovine mastitis are <strong>of</strong> human<br />

origin. However, some are designated as “animal strains” such as S. lentus and S.<br />

caprae which are associated with <strong>goat</strong>s, especially <strong>goat</strong> <strong>milk</strong> (Jay et al., 2005).<br />

Staphylococcus aureus is highly vulnerable to destruction by heat treatment<br />

and to nearly all sanitizing agents. Thus, the presence <strong>of</strong> this bacterium or its<br />

enterotoxins in processed foods or on food processing equipment is generally an<br />

indication <strong>of</strong> poor sanitation. The presence <strong>of</strong> a large number <strong>of</strong> S. aureus organisms<br />

in a food product may indicate poor handling or sanitation; however, it is not<br />

sufficient evidence to incriminate the food products as the cause <strong>of</strong> food poisoning.<br />

The isolated S. aureus must be shown to produce enterotoxins. Conversely, small<br />

staphylococcal populations at the time <strong>of</strong> testing may be remnants <strong>of</strong> large<br />

populations that produced enterotoxins in sufficient quantity to cause food poisoning.<br />

Therefore, the analyst should consider all possibilities when analyzing a food sample<br />

for S. aureus (FDA, 2001).


18<br />

2.4.2 Growth requirements<br />

Staphylococci are typical <strong>of</strong> other Gram-positive bacteria in having a<br />

requirement for certain organic compounds in their nutrition. Amino acids are<br />

required as nitrogen sources, and thiamine and nicotinic acid are required among B<br />

vitamins. When grown anaerobically, they appear to require uracil. In one minimal<br />

medium for aerobic growth and enterotoxin production, monosodium glutamate<br />

serves as C, N and energy source. In general, growth occurs over the range 7 –<br />

47.8 o C and enterotoxins are produced between 10 o C and 46 o C, with the optimum<br />

between 40 o C and 45 o C (Jay et al., 2005).<br />

Growth occurs optimally at pH values <strong>of</strong> 6-7, with minimum and maximum<br />

limits <strong>of</strong> 4.0 and 9.8 – 10.0, respectively. The pH range over which enterotoxin<br />

production occurs is narrower with little toxin production below pH 6.0 but, as with<br />

growth, precise values will vary with the exact nature <strong>of</strong> the medium (Adams and<br />

Moss, 2000).<br />

Jay et al. (2005) also stated that with respect to a w , the staphylococci are<br />

unique in being able to grow at values lower than any other non-halophilic bacteria.<br />

Growth has been demonstrated as low as 0.83 under otherwise ideal conditions,<br />

although 0.86 is the generally recognized as a minimum a w .<br />

2.5 Dairy food safety issues and public health implications<br />

Consumers are increasingly concerned about the safety <strong>of</strong> their food and<br />

uncertain food production practices. Potential threats to human health related to <strong>dairy</strong><br />

products and <strong>dairy</strong> farming include errors in pasteurization, consumption <strong>of</strong> <strong>raw</strong> <strong>milk</strong><br />

products, contamination <strong>of</strong> <strong>milk</strong> products by emerging heat-resistant pathogens,<br />

emergence <strong>of</strong> antimicrobial resistance in zoonotic pathogens, chemical adulteration <strong>of</strong><br />

<strong>milk</strong>, transmission <strong>of</strong> zoonotic pathogens to humans through animal contact and<br />

foodborne diseases related to <strong>dairy</strong> animals (Ruegg, 2003).<br />

Ruegg (2003) also reported that the safety <strong>of</strong> <strong>dairy</strong> products can be enhanced<br />

by adoption <strong>of</strong> a number <strong>of</strong> management practices. Sources <strong>of</strong> microbial


19<br />

contamination <strong>of</strong> <strong>milk</strong> must be minimized by adoption <strong>of</strong> hygienic standards that can<br />

be easily evaluated. There is evidence that microbial contamination <strong>of</strong> <strong>milk</strong> can be<br />

controlled by the use <strong>of</strong> standardized best management practices. Mastitis control<br />

programs focusing on the hygienic harvest <strong>of</strong> <strong>milk</strong> have been widely adopted for at<br />

least 50 years. Worldwide, farmers have achieved tremendous success in reducing the<br />

incidence <strong>of</strong> contagious mastitis by adopting the five basic principles <strong>of</strong> mastitis<br />

control: post-<strong>milk</strong>ing teat disinfection, universal dry cow antibiotic therapy,<br />

appropriate treatment <strong>of</strong> clinical cases, culling <strong>of</strong> chronically infected cows and<br />

regular <strong>milk</strong>ing machine maintenance. Contagious bacteria, such as S. aureus and<br />

Streptococcus agalactiae, are now responsible for less than one-third <strong>of</strong> all mastitis<br />

cases compared with >75% <strong>of</strong> all cases 20 years ago (Hillerton et al., 1995).<br />

Although numerous studies have documented that foodborne pathogens <strong>of</strong><br />

public health significance have been isolated <strong>from</strong> bulk tank <strong>milk</strong> and are capable <strong>of</strong><br />

causing disease in humans, people continue to consume <strong>raw</strong> <strong>milk</strong>. Many farm families<br />

consume <strong>raw</strong> <strong>milk</strong> simply because it is a traditional practice and it is less expensive to<br />

take <strong>milk</strong> <strong>from</strong> the bulk tank than buying pasteurized retail <strong>milk</strong>, some <strong>of</strong> them<br />

believe that <strong>raw</strong> <strong>milk</strong> has a higher nutritional value than pasteurized <strong>milk</strong> (Oliver et<br />

al., 2005).<br />

Oliver et al. (2005) also stated that in addition to direct consumption <strong>of</strong><br />

contaminated <strong>raw</strong> <strong>milk</strong>, introduction <strong>of</strong> <strong>raw</strong> <strong>milk</strong> contaminated with foodborne<br />

pathogens into <strong>dairy</strong> processing plants represents an important risk for the<br />

contamination <strong>of</strong> <strong>milk</strong> products that could lead to consumers’ exposure to pathogenic<br />

bacteria. Although <strong>milk</strong> pasteurization is regarded as an effective method to eliminate<br />

foodborne pathogens, some <strong>dairy</strong> products do not undergo pasteurization (i.e,<br />

specialty cheeses). Furthermore, pathogens such as Listeria monocytogenes survive<br />

and thrive in post-pasteurization processing environments, thus leading to the<br />

recontamination <strong>of</strong> <strong>dairy</strong> products. These two significant exposure pathways pose a<br />

risk to the consumer <strong>from</strong> direct exposure to foodborne pathogens in unpasteurized<br />

<strong>dairy</strong> products as well as <strong>dairy</strong> products which are re-contaminated in the postpasteurization<br />

processing environment. The increasing number <strong>of</strong> incidences in which


20<br />

foodborne pathogens are detected in fluid <strong>milk</strong> and ready-to-eat <strong>dairy</strong> products clearly<br />

indicates that pasteurization is not the ultimate tool to control <strong>milk</strong>borne pathogens. It<br />

is likely that fecal and foodborne pathogen contamination occurs during the<br />

harvesting <strong>of</strong> <strong>raw</strong> <strong>milk</strong> (i.e., <strong>milk</strong>ing, collection and storage), and the farm<br />

environment likely plays a major role in the presence <strong>of</strong> foodborne pathogens in bulk<br />

tank <strong>milk</strong>. Reducing the potential for contamination during <strong>milk</strong> harvesting should<br />

result in the reduction <strong>of</strong> foodborne pathogens in <strong>raw</strong> <strong>milk</strong>.<br />

The <strong>dairy</strong> industry should be concerned about food safety because: (1) bulk<br />

tank <strong>milk</strong> contains several foodborne pathogens that cause human disease, (2)<br />

outbreaks <strong>of</strong> disease in humans have been traced to the consumption <strong>of</strong> <strong>raw</strong><br />

unpasteurized <strong>milk</strong> and have also been traced back to pasteurized <strong>milk</strong>, (3) <strong>raw</strong><br />

unpasteurized <strong>milk</strong> is consumed directly by <strong>dairy</strong> producers and their families, farm<br />

employees and their families, neighbors, etc., (4) <strong>raw</strong> unpasteurized <strong>milk</strong> is consumed<br />

directly by a much larger segment <strong>of</strong> the population via consumption <strong>of</strong> several types<br />

<strong>of</strong> cheeses including ethnic cheeses manufactured <strong>from</strong> unpasteurized <strong>raw</strong> <strong>milk</strong>, (5)<br />

entry <strong>of</strong> foodborne pathogens via contaminated <strong>raw</strong> <strong>milk</strong> into <strong>dairy</strong> food processing<br />

plants can lead to a persistence <strong>of</strong> these pathogens in bi<strong>of</strong>ilms and subsequent<br />

contamination <strong>of</strong> processed food products, (6) pasteurization may not destroy all<br />

foodborne pathogens in <strong>milk</strong> and (7) faulty pasteurization will not destroy all<br />

foodborne pathogens (Oliver et al., 2005).<br />

Not only must research be conducted to solve complex food safety problems,<br />

results <strong>of</strong> that research must be communicated effectively to producers and<br />

consumers. Research and educational efforts identifying potential on-farm risk factors<br />

will better enable <strong>dairy</strong> producers to reduce/prevent foodborne pathogen<br />

contamination <strong>of</strong> <strong>dairy</strong> products leaving the farm. Identification <strong>of</strong> on-farm reservoirs<br />

could be aided with the implementation <strong>of</strong> farm-specific pathogen reduction<br />

programs. Foodborne pathogens, mastitis, <strong>milk</strong> quality and <strong>dairy</strong> food safety are<br />

indeed all interrelated (Oliver et al., 2005).


3. MATERIALS AND METHODS<br />

3.1 Study design<br />

This study was a cross sectional survey to investigate the <strong>microbiological</strong><br />

quality and the association <strong>of</strong> possible risk factors with the <strong>microbiological</strong> status <strong>of</strong><br />

<strong>raw</strong> <strong>goat</strong> <strong>milk</strong>.<br />

3.1.1 Study location<br />

Three <strong>dairy</strong> <strong>goat</strong> farms with herd sizes <strong>of</strong> 600, 400 and 200, respectively, in<br />

the Bogor District, West Java Province, Indonesia were conveniently selected as<br />

sampling sites.<br />

3.1.2 Questionnaire<br />

Questionnaires were administered for collecting information regarding<br />

possible risk factors, which reflected udder, teat and the <strong>goat</strong>’s general condition.<br />

Additional information regarding general farm management and <strong>milk</strong>ing practices<br />

was also collected (Appendix A). The questionnaires were completed by the<br />

investigator during the farm visits.<br />

3.1.3 Type <strong>of</strong> sample<br />

The main <strong>milk</strong> sample that was used in this study was individual udder half<br />

(left and right udder) <strong>milk</strong> <strong>of</strong> lactating <strong>goat</strong>s, which was collected at the time <strong>of</strong><br />

sampling visits. Two parallel bulk <strong>milk</strong> samples were taken <strong>from</strong> each farm at every<br />

visiting time as an additional sample. Ten milliliters <strong>of</strong> <strong>milk</strong> was collected for each<br />

sample, either <strong>from</strong> udder-half or bulk <strong>milk</strong>.


22<br />

3.1.4 Bacterial indicators and laboratory <strong>investigation</strong> standard procedures<br />

General rules for the preparation <strong>of</strong> the initial suspension and decimal<br />

dilutions were based on ISO 6887-1 (1999). US FDA-BAM (United States Food and<br />

Drug Administration – Bacteriological Analytical Manual) online for analysis <strong>of</strong><br />

Aerobic Plate Count (FDA, 2001) was followed for conventional culture <strong>of</strong> total plate<br />

count (TPC), whereas for the total coliforms count, the 3M Petrifilm<br />

interpretation guide for the total coliforms count (Petrifilm, 2001) was followed. To<br />

investigate the presence and enumeration <strong>of</strong> Coagulase Positive and Negative<br />

Staphylococci (Staphylococcus spp.) in the sample, the ISO 6888-1 (1999) standard<br />

technique by using Baird Parker agar medium was used. The California Mastitis Test<br />

(CMT) was done according to Shearer and Harris (2003).<br />

3.2 Sample size determination<br />

Win Episcope 2.0 s<strong>of</strong>tware program was used to determine sample size based<br />

on estimate prevalence. As the most prevalent IMI causing agent according to many<br />

scientific reports, the prevalence <strong>of</strong> CNS in <strong>goat</strong> <strong>milk</strong> was used as the expected<br />

prevalence. Since no report was found <strong>from</strong> Indonesia regarding CNS prevalence in<br />

<strong>goat</strong> <strong>milk</strong>, the prevalence <strong>of</strong> 25% <strong>of</strong> CNS reported by Bergonier et al. (2003) was<br />

used. At a 95% level <strong>of</strong> confidence and 5% accepted error, the sample size <strong>of</strong> 288 was<br />

obtained and then it was rounded up to 300 samples. If the prevalence turns out to be<br />

the expected value, the true prevalence will be between 20.78 and 29.22% (given the<br />

diagnostics were perfect).<br />

3.3 Sampling strategy<br />

Three <strong>dairy</strong> <strong>goat</strong> farms in the Bogor District, West Java Province, Indonesia<br />

with herd sizes <strong>of</strong> 600, 400 and 200 were included in the study. The sampling period<br />

was done in the rainy season, starting <strong>from</strong> early December 2006 until the end <strong>of</strong><br />

March 2007. The sample size was distributed to all farms equally, therefore <strong>from</strong><br />

each farm 100 udder-half <strong>milk</strong> samples (<strong>from</strong> 50 different individual lactating <strong>goat</strong>s)<br />

were collected. The equal distribution <strong>of</strong> sample size to each sampling farm was due


23<br />

to the fact that the object <strong>of</strong> this study was only the lactating <strong>goat</strong>. The number <strong>of</strong><br />

lactating <strong>goat</strong> varied among farms during sampling time, it was depends on the<br />

stocking and reproduction management and also herd size composition (number <strong>of</strong><br />

buck, doe and kid) <strong>of</strong> each farm. The apparently healthy lactating <strong>goat</strong>s were selected<br />

conveniently in a studied farm during a visiting time. Each lactating <strong>goat</strong> was marked<br />

after <strong>milk</strong> sampling to avoid redundancy in the sample collection. Observation <strong>of</strong> the<br />

general condition <strong>of</strong> the selected <strong>dairy</strong> herd, including examination <strong>of</strong> variation in teat<br />

and udder conformation, udder cleanliness and any abnormalities <strong>of</strong> the individual<br />

<strong>goat</strong> was recorded (Appendix A). Approximately 10 ml <strong>of</strong> pre-<strong>milk</strong>ing <strong>milk</strong> samples<br />

were collected into sterile bottles <strong>from</strong> each udder half (left and right). Milk samples<br />

were directly kept at ≤4 o C and transported in an icebox to the laboratory for<br />

<strong>microbiological</strong> analysis within 3 hours. The <strong>milk</strong>ing process was done by the<br />

farmer/<strong>milk</strong>er, teat disinfection was carried out prior to the <strong>milk</strong> sampling using<br />

alcohol and fore-stripping was done before the main sample collection.<br />

3.4 Laboratory procedures<br />

To make 1:10 dilution, the primary dilution (initial suspension) was made by<br />

mixing one ml <strong>of</strong> <strong>milk</strong> sample with nine ml <strong>of</strong> sterile maximum recovery diluent<br />

(MRD) in the test tube, and then continued by further decimal dilution (ISO 6887-<br />

1:1999).<br />

3.4.1 Total Plate Count (TPC) isolation and enumeration<br />

The procedure for TPC isolation and enumeration according to FDA-BAM<br />

(2001) was as follows: 1 ml <strong>of</strong> each dilution is transferred into separate, duplicate,<br />

appropriately marked petri dishes by using sterile pipettes. Re-shake dilution bottle 25<br />

times in 30 cm arc within 7 seconds if it stands more than 3 minutes before it was<br />

pipetted into petri dish. Add 12-15 ml plate count agar (PCA) (cooled to 45 ± 1°C) to<br />

each plate within 15 min <strong>of</strong> original dilution. For <strong>milk</strong> samples, pour an agar control,<br />

pour a dilution water control and pipette water for a pipette control. Add agar to the<br />

latter two for each series <strong>of</strong> samples. Pour agar and dilution water control plates for<br />

each series <strong>of</strong> samples. Sample dilutions and agar medium are immediately mixed


24<br />

thoroughly and uniformly by alternate rotation and back-and-forth motion <strong>of</strong> plates on<br />

flat level surface. After the agar in the petri dishes has solidified, the dishes are<br />

inverted and incubated promptly for 48 ± 2 h at 35°C. The calculation and reporting<br />

are based on standard plate count method recommended by ISO 4833 (2003). Detail<br />

explanation <strong>of</strong> calculation is presented in Appendix C.<br />

3.4.2. Total coliforms isolation and enumeration<br />

Inoculation, incubation and interpretation steps by using Petrifilm<br />

coliforms count are depicted in Figure 1.<br />

1. Petrifilm plate was placed on a flat<br />

surface. Top film was lifted.<br />

2. With pipette perpendicular to Petrifilm<br />

plate, 1 ml <strong>of</strong> sample was placed for<br />

coliforms test onto the centre <strong>of</strong><br />

bottom film. Each sample was<br />

inoculated in two Petrifilm plates.<br />

3. Top film was carefully rolled down to<br />

avoid trapping air bubbles. Do not let<br />

top film drop.


25<br />

4. With ridge side down, spreader was<br />

placed on top film over inoculum.<br />

5. Sample was distributed with a gentle<br />

pressure on the handle <strong>of</strong> the<br />

spreader. Do not twist or slide the<br />

spreader. The spreader was then<br />

lifted and left about one minute for<br />

gel to solidify.<br />

6. Petrifilm plates were incubated with<br />

the clear side up in stacks up to 20 or<br />

less. Incubation time and temperature<br />

<strong>of</strong> 35°C ±1°C for 24 ± 2 h was used<br />

as recommended by ISO 4832 (1991)<br />

standard on general guidance for the<br />

enumeration <strong>of</strong> coliforms.<br />

7. Petrifilm plates were read and the<br />

colonies were counted with reference<br />

to interpretation guide (Petrifilm,<br />

2001).<br />

Figure 1: Inoculation, incubation and interpretation steps by using 3M Petrifilm<br />

for coliforms count plate (Petrifilm, 2001)


26<br />

3.4.3 Isolation and identification <strong>of</strong> coagulase positive and negative staphylococci<br />

(Staphylococcus spp.)<br />

Similar to those samples for TPC and coliforms isolation, <strong>milk</strong> samples for<br />

coagulase positive or negative staphylococci isolation were diluted by 1:10 dilution.<br />

One ml <strong>of</strong> <strong>milk</strong> sample was mixed with nine ml <strong>of</strong> sterile MRD in the test tube to<br />

make initial suspension, and then further decimal dilution was done (ISO 6887-<br />

1:1999).<br />

The flow chart for isolation and identification <strong>of</strong> coagulase positive and<br />

negative staphylococci (ISO 6888-1, 1999) is depicted in Figure 2.<br />

Initial suspension <strong>of</strong> <strong>milk</strong> sample in MRD (1:10) series <strong>of</strong><br />

decimal dilutions<br />

0.1 ml <strong>of</strong> test sample transferred aseptically <strong>from</strong> initial<br />

suspension into two Baird Parker Agar (BPA) plates,<br />

repeat the procedure for further decimal dilution<br />

Plates were inverted and incubated for 24 ± 2 h<br />

at 37 o C in an incubator<br />

After incubation, the positions <strong>of</strong> typical colonies were marked on the<br />

bottom <strong>of</strong> the plates. Plates were re-incubated for further 24 ± 2 h at the<br />

same temperature, new typical colonies and atypical colonies were<br />

marked<br />

Typical and atypical colonies definition were based on<br />

ISO 6887-1:1999 standard*


27<br />

The plates containing a maximum <strong>of</strong> 300 colonies with 150 typical and/or atypical<br />

colonies at two successive dilutions were taken for enumeration. One <strong>of</strong> the plates<br />

should contain at least 15 colonies. Within this step Staphylococcus spp. were<br />

enumerated<br />

The inoculum was spread by using sterile spreader as quickly as<br />

possible, dried with the lids on<br />

For confirmation test a given number <strong>of</strong> colonies were selected (in general 5<br />

typical colonies if there are only typical colonies or 5 atypical colonies if there<br />

are only atypical colonies or 5 typical colonies and 5 atypical colonies if both<br />

types present in each plate)<br />

Confirmation (Coagulase test)<br />

An inoculum was removed with a sterile wire <strong>from</strong> the surface <strong>of</strong> each<br />

selected colony, transferred into a tube <strong>of</strong> Brain Heart Infusion broth (BHI)<br />

and then incubated for 24 ± 2 h at 37 o C<br />

Aseptically 0.1 ml <strong>of</strong> each culture was added to 0.3 ml <strong>of</strong> the rabbit<br />

plasma in sterile haemolysis tubes or bottles and incubated at 37 o C<br />

By tilting the tube, clotting <strong>of</strong> the plasma was examined after<br />

4 h to 6 h <strong>of</strong> incubation time and if the test was negative,<br />

reexamination was carried out at 24 h <strong>of</strong> incubation<br />

The coagulase was considered to be positive if volume <strong>of</strong> clot occupied<br />

more than half <strong>of</strong> original volume <strong>of</strong> liquid or at least at score +3.<br />

Enumeration <strong>of</strong> CPS and CNS according to ISO 6887-1:1999 standard<br />

(Appendix C)<br />

Figure 2: Flow chart for isolation and identification <strong>of</strong> coagulase positive and<br />

negative staphylococci (ISO 6888-1, 1999)


28<br />

Remarks: (*) Typical colonies are black or grey, shining and convex (about 1.5 to 2.5<br />

mm in diameter after incubation <strong>of</strong> 48 h) and surrounded by a clear zone<br />

with immediate contact <strong>of</strong> opalescent ring. Atypical colonies may be<br />

present as shining black colonies with or without a narrow white edge, the<br />

clear zone is absent or barely visible; or grey colonies free <strong>of</strong> clear zones.<br />

The coagulase test was considered to be positive if the volume <strong>of</strong> clot occupies<br />

more than half <strong>of</strong> the original volume <strong>of</strong> the liquid or if the culture yielded at least 3+<br />

coagulase reaction according to the scoring guidance in Figure 3.<br />

Legend:<br />

I<br />

II<br />

III<br />

IV<br />

V<br />

: negative, no evidence <strong>of</strong> fibrin formation<br />

: +1 positive, small unorganized clot<br />

: +2 positive, small organized clot<br />

: +3 positive, large organized clot<br />

: +4 positive, entire content <strong>of</strong> tube coagulase and is not displaced<br />

when tube was inverted<br />

Figure 3: Scoring <strong>of</strong> coagulase test reactions (source: http://www.hc-sc.gc.ca/Tfnan/........../volume1/mfo22_e.html)<br />

As the negative control for each batch <strong>of</strong> plasma, 0.1 ml <strong>of</strong> sterile brain heart<br />

infusion (BHI) broth was added into 0.3 ml <strong>of</strong> rabbit plasma and incubated without<br />

inoculation. For the best to be valid, the control plasma should show no signs <strong>of</strong><br />

clotting.


29<br />

3.4.4 California Mastitis Test (CMT)<br />

CMT was done by mixing 3 ml <strong>of</strong> <strong>milk</strong> sample with 3 ml <strong>of</strong> CMT reagent<br />

(provided by Faculty <strong>of</strong> Veterinary Medicine, CMU) in the CMT paddle. By gently<br />

rocking the CMT plate, the sample and reagent were carefully mixed and the result<br />

was observed within around 20 seconds. The CMT scores were 0, trace, +1, +2 and<br />

+3 (Shearer and Harris, 2003).<br />

For determining the status <strong>of</strong> udder inflammation, the score <strong>of</strong> CMT was<br />

further classified into two categories: negative and positive. The negative score was<br />

represented by CMT scores <strong>of</strong> 0 and “trace” and the positive score (indicator <strong>of</strong><br />

subclinical mastitis/intramammary infection) by CMT scores <strong>of</strong> +1, +2 and +3<br />

(Wakwoya et al., 2006).<br />

3.5 Information regarding potential risk factors <strong>from</strong> questionnaire survey<br />

Information regarding potential risk factors related to <strong>goat</strong>s and udders, as well<br />

as teat condition, was collected by using the questionnaire. The investigator collected<br />

all information during farm visits. There were 10 potential risk factors obtained in this<br />

study and listed in Table 2. Some <strong>of</strong> the risk factors were subjectively scored by the<br />

investigator based on an adoption <strong>of</strong> the available scoring standard for <strong>dairy</strong> cow. The<br />

complete description about the level <strong>of</strong> each factor and/or scoring system can be<br />

found in the Appendix A.<br />

Table 2: List <strong>of</strong> potential risk factors related to <strong>goat</strong>s, udder and teat condition<br />

No. Factors Description<br />

1. Breed Breed <strong>of</strong> animal<br />

2. Parity Parity number<br />

3. Lactation stage Stage <strong>of</strong> lactation<br />

4. Udder symmetry Symmetry <strong>of</strong> udder<br />

5. Udder hygiene Score <strong>of</strong> udder hygiene<br />

6. Teat end condition Score <strong>of</strong> teat end condition


30<br />

No. Factors Description<br />

7. Teat skin condition Score <strong>of</strong> teat skin condition<br />

8. Teat shape Teat shape condition<br />

9. Udder inflammation status Inflammatory status <strong>of</strong> the udder (based<br />

on CMT test result)<br />

10. Milk appearance Normality <strong>of</strong> <strong>milk</strong> appearance<br />

General farm, <strong>milk</strong>ing and management practice information was also<br />

collected by the investigator during farm visits. The detailed information about this<br />

matter can be seen in Appendix A.<br />

3.6 Data management and statistical analysis<br />

Laboratory and questionnaire data were managed by using Micros<strong>of</strong>t Office<br />

Excel 2003. Databases were prepared for each type <strong>of</strong> data and later merged into one.<br />

Descriptive statistics were used to describe enumeration and prevalence data. The<br />

prevalence estimates were determined by using the standard formula (i.e. the number<br />

<strong>of</strong> positive samples divided by the number <strong>of</strong> total samples examined). Chi-square<br />

univariate analysis was performed to evaluate the impact <strong>of</strong> each potential risk factor<br />

(derived <strong>from</strong> the questionnaire responses) to the pathogenic outcomes (present or not<br />

present) in samples. McNemar Chi-square test was used to compare the true<br />

proportion <strong>of</strong> positive results among two testing methods, whilst Cohen’s kappa<br />

coefficient was used to evaluate the agreement between two test results. The logistic<br />

regression model for multivariate analysis was carried out to evaluate the impacts <strong>of</strong><br />

particular risk factors without interaction <strong>from</strong> the other factors. Mann-Whitney U test<br />

or Kruskall-Wallis one way ANOVA (depending on the number <strong>of</strong> data groups) were<br />

used to evaluate statistical significance in bacteria population among farms and within<br />

the evaluated potential risk factors (Petrie and Watson, 1999; Dawson and Trapp,<br />

2004).


4. RESULTS<br />

4.1 Results <strong>of</strong> bacterial isolation and enumeration<br />

4.1.1 Results <strong>from</strong> individual udder-half <strong>milk</strong> samples<br />

Table 3 shows the compilation <strong>of</strong> some selected statistical values <strong>of</strong> indicator<br />

bacterial count data <strong>from</strong> udder-half <strong>milk</strong> samples. The median values <strong>of</strong> overall<br />

samples (n=300) for TPC, coliforms, Staphylococcus spp., CPS and CNS were 3.74,<br />

0.70, 3.00, 1.70 and 2.52 log cfu/ml, respectively.<br />

It should be noted that for the enumeration purpose, the samples yielded no<br />

growth <strong>of</strong> bacteria (negative results) were registered with half <strong>of</strong> the detection limit <strong>of</strong><br />

bacterial isolation method (10:2 = 5 colonies = log 0.70 for coliforms; 100:2 = 50<br />

colonies = log 1.70 for Staphylococcus spp., CPS and CNS).<br />

Within the farm level (n=100/farm), the highest median value <strong>of</strong> TPC,<br />

coliforms, Staphylococcus spp. and CNS were 3.92 log cfu/ml (Farm 2), 2.39 log<br />

cfu/ml (Farm 3), 3.34 log cfu/ml (Farm 2) and 2.85 log cfu/ml (Farm 2), respectively,<br />

whereas the median values <strong>of</strong> CPS <strong>from</strong> every farm were the same. Statistically<br />

significant differences (P


32<br />

Table 3: Selected statistical value <strong>of</strong> indicator bacterial counts <strong>from</strong> udder half <strong>milk</strong><br />

samples (n= 100/farm)<br />

No.<br />

Selected Overall Farm Farm Farm<br />

Indicator<br />

Statistical [n=300] 1 2 3<br />

Bacteria<br />

Value<br />

log cfu/ml<br />

1. Total Plate Median 3.74 3.03 3.92 3.77<br />

Count (TPC) Maximum 6.96 6.01 6.40 6.96<br />

Minimum 0.70 1.00 1.30 0.70<br />

IQR* 1.68 2.10 1.06 1.79<br />

2. Coliforms Median 0.70 0.70 1.00 2.39<br />

Maximum 5.99 5.99 4.24 4.66<br />

Minimum 0.70 0.70 0.70 0.70<br />

IQR* 1.41 0.00 1.20 2.12<br />

3. Staphylococcus Median 3.00 2.59 3.34 2.83<br />

spp.<br />

Maximum 6.51 6.10 6.51 5.70<br />

Minimum 1.70 1.70 1.70 1.70<br />

IQR* 2.10 2.48 1.70 2.00<br />

4. Coagulase Median 1.70 1.70 1.70 1.70<br />

Positive Maximum 6.18 6.02 6.18 5.51<br />

Staphylococci Minimum 1.70 1.70 1.70 1.70<br />

(CPS) IQR* 1.30 1.25 1.75 0.99<br />

5. Coagulase Median 2.52 2.00 2.85 2.60<br />

Negative Maximum 6.41 6.09 6.41 5.49<br />

Staphylococci Minimum 1.70 1.70 1.70 1.70<br />

(CNS) IQR* 2.01 1.67 2.11 2.21<br />

* IQR = Inter Quartile Range<br />

P-value<br />

(among<br />

farms)<br />

0.002<br />

0.000<br />

0.029<br />

0.298<br />

0.003


33<br />

7.00<br />

6.00<br />

5.00<br />

TPC (log cfu/ml)<br />

4.00<br />

3.00<br />

2.00<br />

1.00<br />

0.00<br />

1<br />

2<br />

Farm ID<br />

3<br />

Figure 4: Box and Whisker plots <strong>of</strong> TPC in three farms compared to the maximum<br />

limit <strong>of</strong> available standards ( = SNI, = EC Directive and “Milchverordnung”).<br />

(ο) = outlier values <strong>from</strong> data distribution which can be represented either<br />

as the maximum or minimum value<br />

6.00<br />

5.00<br />

Coliforms (log cfu/ml)<br />

4.00<br />

3.00<br />

2.00<br />

1.00<br />

0.00<br />

1<br />

2<br />

Farm ID<br />

3<br />

Figure 5: Box and Whisker plots <strong>of</strong> coliforms counts in three farms compared to the<br />

maximum limit <strong>of</strong> available standards ( = SNI, = EC Directive and<br />

“Milchverordnung”). (*) values <strong>of</strong> data distribution, (ο) = outlier value <strong>from</strong> data<br />

distribution which is represented as the maximum value


34<br />

Box and Whisker plots in Figure 5 show the descriptive statistics <strong>of</strong> coliforms<br />

counts in each sampling farm. Only the median value <strong>of</strong> the coliforms count <strong>from</strong><br />

farm 3 [2.39 log cfu/ml] (Table 3), exceeded the maximum limit <strong>of</strong> available<br />

standards, i.e. 1.3 log cfu/ml <strong>from</strong> SNI (SNI 01-3141) (BSN, 1998) and 2 log cfu/ml<br />

in EC Directive 92/46/EEC (1992) and German “Milchverordnung” for<br />

“Vorzugsmilch” (BGBl Teil I Nr. 58 S 2794, 2004). However all the farms had<br />

maximum coliforms values (Table 3) exceeding the maximum limits <strong>of</strong> those<br />

standards.<br />

8.00<br />

6.00<br />

CPS (log cfu/ml)<br />

4.00<br />

2.00<br />

0.00<br />

1<br />

2<br />

Farm ID<br />

3<br />

Figure 6: Box and Whisker plots <strong>of</strong> CPS counts in three farms compared to the<br />

maximum limit <strong>of</strong> S. aureus in available standards ( = SNI, = EC Directive<br />

and “Milchverordnung”). (ο) = outlier values <strong>from</strong> data distribution which can<br />

be represented as the maximum value<br />

Figure 6 shows the descriptive statistics <strong>of</strong> CPS counts in each sampling farm.<br />

CPS was compared with the S. aureus maximum limit standard, because S. aureus is<br />

the major species within CPS. ISO 6888-1 standard (1999), which was used as the<br />

standard procedure for CPS isolation, stated that the standard was mainly concerned<br />

about S. aureus, but it was possible that other minor CPS species existed, especially


35<br />

when the coagulase test results showed weak reaction. None <strong>of</strong> the median values <strong>of</strong><br />

CPS counts <strong>from</strong> every farm (Table 3) exceeded the maximum limit <strong>of</strong> S. aureus<br />

(2 log cfu/ml) <strong>from</strong> SNI (SNI 01-3141) (BSN, 1998) and 3.3 log cfu/ml in EC<br />

Directive 92/46/EEC (1992) and German “Milchverordnung” (BGBl Teil I Nr. 58 S<br />

2794, 2004). All farms had maximum values <strong>of</strong> CPS counts exceeding the maximum<br />

limits <strong>of</strong> those standards.<br />

CNS<br />

2.52<br />

I ndic ato r ba cter ia<br />

CPS<br />

Staphylococcus spp.<br />

Coliforms<br />

TPC<br />

0.70<br />

1.70<br />

3.00<br />

3.74<br />

0 0.5 1 1.5 2 2.5 3 3.5 4<br />

Median Value (log cfu/ml)<br />

Figure 7: Bar charts <strong>of</strong> median values <strong>of</strong> indicator bacterial counts <strong>from</strong> overall<br />

udder-half <strong>milk</strong> samples (n=300)<br />

Median values <strong>of</strong> TPC, coliforms and CPS <strong>from</strong> overall udder-half <strong>milk</strong><br />

samples (Figure 7) did not exceed the maximum limit <strong>of</strong> each bacterium standard both<br />

<strong>from</strong> SNI [TPC = 6 log cfu/ml; coliforms = 1.3 log cfu/ml; S. aureus = 2 log cfu/ml]<br />

(SNI 01-3141) (BSN, 1998) and <strong>from</strong> the European (EC, 1992) and German<br />

“Milchverordnung” (BGBl, 2004) [TPC = 5.7 log cfu/ml; coliforms = 2 log cfu/ml; S.<br />

aureus = 3.3 log cfu/ml]. However, TPC, coliforms and CPS counts <strong>of</strong> the overall<br />

udder-half <strong>milk</strong> samples had maximum values which exceeded the maximum limit for<br />

each bacterium in all three available standards. The maximum values <strong>of</strong> each<br />

indicator bacteria were 6.96, 5.99 and 6.18 log cfu/ml for TPC, coliforms and CPS<br />

respectively (Table 3).


36<br />

Table 4 shows indicator bacterial count <strong>from</strong> udder-half <strong>milk</strong> samples among<br />

breeds <strong>of</strong> <strong>goat</strong> in each farm. Statistically significant differences (P


37<br />

Table 4: Indicator bacterial count <strong>from</strong> udder-half <strong>milk</strong> samples among breeds <strong>of</strong><br />

<strong>goat</strong> in each farm (n = 100/farm)<br />

Indicator Bacteria Farm Breed* n Median (log<br />

cfu/ml)<br />

P-value<br />

(among<br />

breeds)<br />

TPC<br />

1<br />

1 72 3.69<br />

2 20 2.34 0.012<br />

3 8 2.88<br />

2<br />

1 72 3.99<br />

2 14 3.92 0.120<br />

3 14 3.20<br />

3<br />

1 32 2.83<br />

2 68 4.31 0.000<br />

3 - -<br />

Coliforms<br />

1<br />

1 72 0.70<br />

2 20 0.70 0.293<br />

3 8 0.70<br />

2<br />

1 72 1.00<br />

2 14 0.70 0.185<br />

3 14 1.15<br />

3<br />

1 32 0.70<br />

2 68 2.75 0.000<br />

3 - -<br />

Staphylococcus spp. 1<br />

1 72 2.91<br />

2 20 2.15 0.076<br />

3 8 1.70<br />

2<br />

1 72 3.75<br />

2 14 3.34 0.433<br />

3 14 2.98<br />

3<br />

1 32 3.22<br />

2 68 2.63 0.121<br />

3 - -<br />

CPS<br />

1<br />

1 72 1.70<br />

2 20 1.70 0.634<br />

3 8 1.70<br />

2<br />

1 72 1.70<br />

2 14 1.70 0.265<br />

3 14 2.30<br />

3<br />

1 32 1.70<br />

2 68 1.70 0.507<br />

3 - -<br />

CNS<br />

1<br />

1 72 2.15<br />

2 20 1.70 0.222<br />

3 8 1.70<br />

2<br />

1 72 3.04<br />

2 14 3.17<br />

0.164<br />

3 14 2.29<br />

3<br />

1 32 3.00<br />

2 68 2.46 0.034<br />

3 - -<br />

* Breed <strong>of</strong> <strong>goat</strong>: 1. Ettawa crossbreed, 2. Saanen crossbreed, 3. Jawarandu


38<br />

Table 5: Total Plate Count <strong>from</strong> udder-half <strong>milk</strong> samples among levels <strong>of</strong> each factor<br />

(n = 300)<br />

Factors/Level* n Median<br />

(log cfu/ml)<br />

Breed<br />

- Ettawa Crossbreed (EC)<br />

- Saanen Crossbreed<br />

- Jawarandu (Local crossbreed)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Udder symmetry<br />

- Yes<br />

- No<br />

Udder hygiene<br />

- Free <strong>of</strong> dirt<br />

- Slightly dirty<br />

Teat end condition<br />

- No ring<br />

- Smooth rough ring<br />

Teat skin condition<br />

- Free <strong>from</strong> scales/smooth<br />

- Shows some scaling<br />

Teat shape<br />

- Normal<br />

- Dilatated<br />

- General dilatated<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

Milk appearance<br />

- Normal<br />

- Abnormal<br />

176<br />

102<br />

22<br />

66<br />

114<br />

80<br />

32<br />

8<br />

183<br />

66<br />

51<br />

176<br />

124<br />

296<br />

4<br />

225<br />

75<br />

295<br />

5<br />

166<br />

117<br />

17<br />

186<br />

114<br />

3.76<br />

3.87<br />

3.06<br />

3.25<br />

3.91<br />

3.67<br />

3.95<br />

4.18<br />

3.72<br />

3.64<br />

3.99<br />

3.57<br />

3.97<br />

3.74<br />

4.60<br />

3.53<br />

4.12<br />

3.74<br />

4.00<br />

3.26<br />

4.13<br />

4.28<br />

4.15<br />

2.84<br />

P-value<br />

0.035<br />

0.010<br />

0.392<br />

0.180<br />

0.271<br />

0.001<br />

0.892<br />

0.000<br />

0.000<br />

293 3.73<br />

0.028<br />

7 4.57<br />

*Detail explanation <strong>of</strong> each factor level is presented in Appendix A


39<br />

Table 6: Coliforms counts <strong>from</strong> udder-half <strong>milk</strong> samples among levels <strong>of</strong> each factor<br />

(n = 300)<br />

Factors/Level n Median<br />

(log cfu/ml)<br />

Breed<br />

- Ettawa Crossbreed (EC)<br />

- Saanen Crossbreed<br />

- Jawarandu (Local crossbreed)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Udder symmetry<br />

- Yes<br />

- No<br />

Udder hygiene<br />

- Free <strong>of</strong> dirt<br />

- Slightly dirty<br />

Teat end condition<br />

- No ring<br />

- Smooth rough ring<br />

Teat skin condition<br />

- Free <strong>from</strong> scales/smooth<br />

- Shows some scaling<br />

Teat shape<br />

- Normal<br />

- Dilated<br />

- General dilated<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

Milk appearance<br />

- Normal<br />

- Abnormal<br />

176<br />

102<br />

22<br />

66<br />

114<br />

80<br />

32<br />

8<br />

183<br />

66<br />

51<br />

176<br />

124<br />

296<br />

4<br />

225<br />

75<br />

295<br />

5<br />

166<br />

117<br />

17<br />

186<br />

114<br />

293<br />

7<br />

0.70<br />

2.11<br />

0.70<br />

0.70<br />

0.98<br />

0.70<br />

0.70<br />

1.00<br />

0.70<br />

0.70<br />

0.96<br />

0.70<br />

0.70<br />

0.70<br />

2.63<br />

0.70<br />

0.70<br />

0.70<br />

0.70<br />

0.70<br />

1.00<br />

0.70<br />

0.70<br />

0.70<br />

0.70<br />

1.30<br />

P-value<br />

0.000<br />

0.065<br />

0.629<br />

0.833<br />

0.104<br />

0.459<br />

0.181<br />

0.111<br />

0.415<br />

0.152


40<br />

Table 7: Staphylococcus spp. count <strong>from</strong> udder-half <strong>milk</strong> samples among levels <strong>of</strong><br />

each factor (n = 300)<br />

Factors/Level n Median<br />

(log cfu/ml)<br />

Breed<br />

- Ettawa Crossbreed (EC)<br />

- Saanen Crossbreed<br />

- Jawarandu (Local crossbreed)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Udder symmetry<br />

- Yes<br />

- No<br />

Udder hygiene<br />

- Free <strong>of</strong> dirt<br />

- Slightly dirty<br />

Teat end condition<br />

- No ring<br />

- Smooth rough ring<br />

Teat skin condition<br />

- Free <strong>from</strong> scales/smooth<br />

- Shows some scaling<br />

Teat shape<br />

- Normal<br />

- Dilated<br />

- General dilated<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

Milk appearance<br />

- Normal<br />

- Abnormal<br />

176<br />

102<br />

22<br />

66<br />

114<br />

80<br />

32<br />

8<br />

183<br />

66<br />

51<br />

176<br />

124<br />

296<br />

4<br />

225<br />

75<br />

295<br />

5<br />

166<br />

117<br />

17<br />

186<br />

114<br />

293<br />

7<br />

3.30<br />

2.68<br />

2.77<br />

2.48<br />

2.82<br />

3.70<br />

3.15<br />

4.01<br />

3.10<br />

2.48<br />

3.30<br />

3.09<br />

2.90<br />

3.02<br />

2.09<br />

2.80<br />

3.75<br />

3.00<br />

3.92<br />

2.79<br />

3.34<br />

3.42<br />

3.56<br />

2.48<br />

3.00<br />

3.53<br />

P-value<br />

0.014<br />

0.000<br />

0.004<br />

0.774<br />

0.257<br />

0.003<br />

0.406<br />

0.052<br />

0.000<br />

0.738


41<br />

Table 8: Coagulase positive staphylococci (CPS) count <strong>from</strong> udder-half <strong>milk</strong><br />

samples among levels <strong>of</strong> each factor (n = 300)<br />

Factors/Level n Median<br />

(log cfu/ml)<br />

Breed<br />

- Ettawa Crossbreed (EC)<br />

- Saanen Crossbreed<br />

- Jawarandu (Local crossbreed)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Udder symmetry<br />

- Yes<br />

- No<br />

Udder hygiene<br />

- Free <strong>of</strong> dirt<br />

- Slightly dirty<br />

Teat end condition<br />

- No ring<br />

- Smooth rough ring<br />

Teat skin condition<br />

- Free <strong>from</strong> scales/smooth<br />

- Shows some scaling<br />

Teat shape<br />

- Normal<br />

- Dilated<br />

- General dilated<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

Milk appearance<br />

- Normal<br />

- Abnormal<br />

176<br />

102<br />

22<br />

66<br />

114<br />

80<br />

32<br />

8<br />

183<br />

66<br />

51<br />

176<br />

124<br />

296<br />

4<br />

225<br />

75<br />

295<br />

5<br />

166<br />

117<br />

17<br />

186<br />

114<br />

293<br />

7<br />

1.70<br />

1.70<br />

2.00<br />

1.70<br />

1.70<br />

1.70<br />

2.00<br />

3.87<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

3.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

1.70<br />

2.30<br />

P-value<br />

0.282<br />

0.000<br />

0.010<br />

0.774<br />

0.132<br />

0.003<br />

0.085<br />

0.588<br />

0.000<br />

0.738


42<br />

Table 9: Coagulase negative staphylococci (CNS) count <strong>from</strong> udder-half <strong>milk</strong><br />

samples among levels <strong>of</strong> each factor (n = 300)<br />

Factors/Level n Median<br />

(log cfu/ml)<br />

Breed<br />

- Ettawa Crossbreed (EC)<br />

- Saanen Crossbreed<br />

- Jawarandu (Local crossbreed)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Udder symmetry<br />

- Yes<br />

- No<br />

Udder hygiene<br />

- Free <strong>of</strong> dirt<br />

- Slightly dirty<br />

Teat end condition<br />

- No ring<br />

- Smooth rough ring<br />

Teat skin condition<br />

- Free <strong>from</strong> scales/smooth<br />

- Shows some scaling<br />

Teat shape<br />

- Normal<br />

- Dilated<br />

- General dilated<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

Milk appearance<br />

- Normal<br />

- Abnormal<br />

176<br />

102<br />

22<br />

66<br />

114<br />

80<br />

32<br />

8<br />

183<br />

66<br />

51<br />

176<br />

124<br />

296<br />

4<br />

225<br />

75<br />

295<br />

5<br />

166<br />

117<br />

17<br />

186<br />

114<br />

293<br />

7<br />

2.76<br />

2.37<br />

1.85<br />

2.13<br />

2.30<br />

2.90<br />

2.67<br />

3.59<br />

2.74<br />

2.15<br />

2.30<br />

2.60<br />

2.48<br />

2.58<br />

2.09<br />

2.48<br />

3.13<br />

2.48<br />

2.85<br />

2.48<br />

2.66<br />

2.00<br />

2.74<br />

2.00<br />

2.48<br />

2.66<br />

P-value<br />

0.028<br />

0.023<br />

0.035<br />

0.317<br />

0.551<br />

0.003<br />

0.625<br />

0.134<br />

0.000<br />

0.738


43<br />

Table 10 shows overall and farm level prevalence <strong>of</strong> indicator bacteria <strong>from</strong><br />

udder-half <strong>milk</strong> samples. Overall prevalence <strong>of</strong> coliforms, Staphylococcus spp., CPS<br />

and CNS were 46.3, 78.7, 37.7 and 66.0%, respectively.<br />

Within the farm level, the highest prevalence for each indicator bacteria were<br />

77% for coliforms (Farm 3), 86% for Staphylococcus spp. (Farm 2), 43% for CPS<br />

(Farm 2) and 75% for CNS (Farm 2). Statistically significant difference was observed<br />

only for the prevalence <strong>of</strong> coliforms and CNS among farms.<br />

Table 10: Proportion <strong>of</strong> positive samples for indicator bacteria <strong>from</strong> udder-half <strong>milk</strong><br />

samples<br />

Indicator<br />

Bacteria<br />

Factor/level<br />

n<br />

No. <strong>of</strong><br />

positive/contaminated<br />

samples<br />

Prevalence<br />

(%)<br />

Coliforms Overall 300 139 46.3<br />

By Farm<br />

- Farm 1<br />

- Farm 2<br />

- Farm 3<br />

100<br />

100<br />

100<br />

6<br />

56<br />

77<br />

6<br />

56<br />

77<br />

Staphylococcus<br />

spp.<br />

Overall 300 236 78.7<br />

By Farm<br />

- Farm 1<br />

- Farm 2<br />

- Farm 3<br />

100<br />

100<br />

100<br />

72<br />

86<br />

78<br />

72<br />

86<br />

78<br />

CPS Overall 300 113 37.7<br />

By Farm<br />

- Farm 1<br />

- Farm 2<br />

- Farm 3<br />

100<br />

100<br />

100<br />

35<br />

43<br />

35<br />

35<br />

43<br />

35<br />

CNS Overall 300 198 66.0<br />

By Farm<br />

- Farm 1<br />

- Farm 2<br />

- Farm 3<br />

100<br />

100<br />

100<br />

53<br />

75<br />

70<br />

53<br />

75<br />

70<br />

P-value<br />

0.000<br />

0.053<br />

0.403<br />

0.003


44<br />

Table 11: Proportion <strong>of</strong> positive samples for indicator bacteria <strong>from</strong> udder-half <strong>milk</strong><br />

samples among breeds <strong>of</strong> <strong>goat</strong> in each farm<br />

Indicator<br />

Bacteria<br />

Farm Breed* n No. <strong>of</strong><br />

positive<br />

samples<br />

1<br />

Prevalence<br />

(%)<br />

P-value<br />

(among<br />

breeds)<br />

Coliforms<br />

1 72 6 8.30<br />

2 20 0 0.00 0.463<br />

3 8 0 0.00<br />

2<br />

1 72 42 58.3<br />

2 14 5 35.7 0.250<br />

3 14 9 64.3<br />

3<br />

1 32 13 40.6<br />

2 68 64 94.1 0.000<br />

3 - - -<br />

Staphylococcus 1<br />

1 72 56 77.7<br />

spp.<br />

2 20 13 65.0 0.036<br />

3 8 3 37.5<br />

2<br />

1 72 63 87.5<br />

2 14 12 85.7 0.657<br />

3 14 11 78.6<br />

3<br />

1 32 25 78.1<br />

2 68 53 77.9 1.000<br />

3 - - -<br />

CPS<br />

1<br />

1 72 26 36.1<br />

2 20 7 35.0 0.939<br />

3 8 2 25.0<br />

2<br />

1 72 29 40.3<br />

2 14 4 28.6 0.050<br />

3 14 10 71.4<br />

3<br />

1 32 12 37.5<br />

2 68 23 33.8 0.893<br />

3 - - -<br />

CNS 1<br />

1 72 42 58.3<br />

2 20 8 40.0 0.234<br />

3 8 3 37.5<br />

2<br />

1 72 56 77.8<br />

2 14 11 78.6 0.324<br />

3 14 8 57.1<br />

3<br />

1 32 24 75.0<br />

2 68 45 66.2 0.510<br />

3 - - -<br />

* Breed <strong>of</strong> <strong>goat</strong>: 1. Ettawa crossbreed, 2. Saanen crossbreed, 3. Jawarandu


45<br />

Table 11 shows the prevalence <strong>of</strong> indicator bacteria <strong>from</strong> udder-half <strong>milk</strong><br />

samples among breeds <strong>of</strong> <strong>goat</strong> in each farm. Statistically significant difference<br />

(P


46<br />

Data in Table 12 show number <strong>of</strong> coliforms positive samples <strong>from</strong> overall<br />

udder-half <strong>milk</strong> samples in each level <strong>of</strong> potential risk factors. Only one out <strong>of</strong> 10<br />

potential risk factors (breed <strong>of</strong> <strong>goat</strong>) was significantly (P


47<br />

Table 14: Summary results <strong>of</strong> the assessment <strong>of</strong> associations between sample<br />

prevalence <strong>of</strong> Staphylococcus spp. with potential risk factors (univariate analysis)<br />

Factors/Level n n (+) n (-) % (+) P-value<br />

Breed<br />

- Ettawa Crossbreed (EC)<br />

- Saanen Crossbreed<br />

- Jawarandu (Local crossbreed)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Udder symmetry<br />

- Yes<br />

- No<br />

Udder hygiene<br />

- Free <strong>of</strong> dirt<br />

- Slightly dirty<br />

Teat end condition<br />

- No ring<br />

- Smooth rough ring<br />

Teat skin condition<br />

- Free <strong>from</strong> scales/smooth<br />

- Shows some scaling<br />

Teat shape<br />

- Normal<br />

- Dilated<br />

- General dilated<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

Milk appearance<br />

- Normal<br />

- Abnormal<br />

176<br />

102<br />

22<br />

66<br />

114<br />

80<br />

32<br />

8<br />

183<br />

66<br />

51<br />

176<br />

124<br />

296<br />

4<br />

225<br />

75<br />

295<br />

5<br />

166<br />

117<br />

17<br />

186<br />

114<br />

293<br />

7<br />

144<br />

78<br />

14<br />

47<br />

86<br />

67<br />

28<br />

8<br />

152<br />

44<br />

40<br />

138<br />

98<br />

234<br />

2<br />

171<br />

65<br />

231<br />

5<br />

124<br />

100<br />

12<br />

157<br />

79<br />

230<br />

6<br />

32<br />

24<br />

8<br />

19<br />

28<br />

13<br />

4<br />

0<br />

31<br />

22<br />

11<br />

38<br />

26<br />

62<br />

2<br />

54<br />

10<br />

64<br />

0<br />

42<br />

17<br />

5<br />

29<br />

35<br />

63<br />

1<br />

81.8<br />

76.5<br />

63.6<br />

71.2<br />

75.4<br />

83.8<br />

87.5<br />

100<br />

83.1<br />

66.7<br />

78.4<br />

78.4<br />

79.0<br />

79.1<br />

50.0<br />

76.0<br />

86.7<br />

78.3<br />

100.0<br />

74.7<br />

85.5<br />

70.6<br />

84.4<br />

69.3<br />

78.5<br />

85.7<br />

0.117<br />

0.100<br />

0.021<br />

1.000<br />

0.427<br />

0.073<br />

0.533<br />

0.066<br />

0.003<br />

1.000<br />

The results <strong>of</strong> logistic regression <strong>of</strong> two risk factors which were significantly<br />

associated with sample prevalence <strong>of</strong> Staphylococcus spp in univariate analysis are<br />

shown in Table 15. The second stage <strong>of</strong> lactation had significantly lower


48<br />

Staphylococcus spp. contamination in the samples than the first lactation stage<br />

(OR=0.392, P=0.005). The odd ratio (OR) <strong>of</strong> udder inflammation status factor was<br />

greater than one, meaning that factor was positively associated with the presence <strong>of</strong><br />

Staphylococcus spp. in the samples. Therefore the udder with inflammation had<br />

significantly higher results <strong>of</strong> Staphylococcus spp. positive samples than udder<br />

without inflammation (OR= 2.490, P=0.002). It can also be said that the risk <strong>of</strong><br />

having Staphylococcus spp. positive <strong>milk</strong> samples was 2.49 times more likely if the<br />

udder had inflammation than if it had not.<br />

Table 15: Logistic regression <strong>of</strong> the risk factor associated with sample prevalence <strong>of</strong><br />

Staphylococcus spp. (multivariate analysis)<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Factors/Level OR P-value 95% Confidence<br />

Interval<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

1<br />

0.392<br />

0.662<br />

2.490<br />

1<br />

-<br />

0.005<br />

0.305<br />

0.002<br />

-<br />

0<br />

[0.203, 0.755]<br />

[0.301, 1.456]<br />

[1.403. 4.418]<br />

0<br />

Table 16 shows number <strong>of</strong> CPS positive samples in each level <strong>of</strong> potential risk<br />

factors. Only three out <strong>of</strong> 10 potential risk factors were significantly (P


49<br />

Table 16: Summary results <strong>of</strong> the assessment <strong>of</strong> associations between sample<br />

prevalence <strong>of</strong> CPS with potential risk factors (univariate analysis)<br />

Factors/Level n n (+) n (-) % (+) P-value<br />

Breed<br />

- Ettawa Crossbreed (EC)<br />

- Saanen Crossbreed<br />

- Jawarandu (Local crossbreed)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Udder symmetry<br />

- Yes<br />

- No<br />

Udder hygiene<br />

- Free <strong>of</strong> dirt<br />

- Slightly dirty<br />

Teat end condition<br />

- No ring<br />

- Smooth rough ring<br />

Teat skin condition<br />

- Free <strong>from</strong> scales/smooth<br />

- Shows some scaling<br />

Teat shape<br />

- Normal<br />

- Dilated<br />

- General dilated<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

Milk appearance<br />

- Normal<br />

- Abnormal<br />

176<br />

102<br />

22<br />

66<br />

114<br />

80<br />

32<br />

8<br />

183<br />

66<br />

51<br />

176<br />

124<br />

296<br />

4<br />

225<br />

75<br />

295<br />

5<br />

166<br />

117<br />

17<br />

186<br />

114<br />

293<br />

7<br />

67<br />

34<br />

12<br />

20<br />

34<br />

35<br />

18<br />

6<br />

75<br />

16<br />

22<br />

70<br />

43<br />

113<br />

0<br />

80<br />

33<br />

109<br />

4<br />

62<br />

43<br />

8<br />

82<br />

31<br />

108<br />

5<br />

109<br />

68<br />

10<br />

46<br />

80<br />

45<br />

14<br />

2<br />

108<br />

50<br />

29<br />

106<br />

81<br />

183<br />

4<br />

145<br />

42<br />

186<br />

1<br />

104<br />

74<br />

9<br />

104<br />

83<br />

185<br />

2<br />

38.1<br />

33.3<br />

54.5<br />

30.0<br />

29.8<br />

43.8<br />

56.3<br />

75.0<br />

41.0<br />

24.2<br />

43.1<br />

39.8<br />

34.7<br />

38.2<br />

0.00<br />

35.6<br />

44.0<br />

36.9<br />

80.0<br />

37.3<br />

36.8<br />

47.1<br />

44.1<br />

27.2<br />

36.9<br />

71.4<br />

0.174<br />

0.004<br />

0.037<br />

0.438<br />

0.296<br />

0.242<br />

0.132<br />

0.709<br />

0.005<br />

0.141


50<br />

Table 17: Logistic regression <strong>of</strong> the risk factor associated with sample prevalence <strong>of</strong><br />

CPS (multivariate analysis)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Factors/Level OR P-value 95% Confidence<br />

Interval<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

1.000<br />

0.900<br />

1.853<br />

1.764<br />

6.033<br />

1.000<br />

0.814<br />

1.449<br />

2.622<br />

1.000<br />

-<br />

0.778<br />

0.118<br />

0.253<br />

0.050<br />

-<br />

0.577<br />

0.333<br />

0.001<br />

-<br />

0<br />

[0.431, 1.876]<br />

[0.856, 4.013]<br />

[0.666, 4.672]<br />

[0.999, 36.455]<br />

0<br />

[0.395, 1.679]<br />

[0.684, 3.070]<br />

[1.487, 4.623]<br />

0<br />

None <strong>of</strong> the potential risk factors was significantly (P


51<br />

Table 18: Summary results <strong>of</strong> the assessment <strong>of</strong> associations between prevalence <strong>of</strong><br />

CNS with potential risk factors (univariate analysis)<br />

Factors/Level n n (+) n (-) % (+) P-value<br />

Breed<br />

- Ettawa Crossbreed (EC)<br />

- Saanen Crossbreed<br />

- Jawarandu (Local crossbreed)<br />

Parity<br />

- First<br />

- Second<br />

- Third<br />

- Fourth<br />

- Fifth<br />

Lactation stage<br />

- First<br />

- Second<br />

- Third<br />

Udder symmetry<br />

- Yes<br />

- No<br />

Udder hygiene<br />

- Free <strong>of</strong> dirt<br />

- Slightly dirty<br />

Teat end condition<br />

- No ring<br />

- Smooth rough ring<br />

Teat skin condition<br />

- Free <strong>from</strong> scales/smooth<br />

- Shows some scaling<br />

Teat shape<br />

- Normal<br />

- Dilated<br />

- General dilated<br />

Udder inflammation status<br />

- Yes<br />

- No<br />

Milk appearance<br />

- Normal<br />

- Abnormal<br />

176<br />

102<br />

22<br />

66<br />

114<br />

80<br />

32<br />

8<br />

183<br />

66<br />

51<br />

176<br />

124<br />

296<br />

4<br />

225<br />

75<br />

295<br />

5<br />

166<br />

117<br />

17<br />

186<br />

114<br />

293<br />

7<br />

122<br />

64<br />

11<br />

40<br />

72<br />

56<br />

22<br />

7<br />

129<br />

38<br />

30<br />

115<br />

82<br />

195<br />

2<br />

142<br />

55<br />

193<br />

4<br />

105<br />

83<br />

9<br />

130<br />

67<br />

192<br />

5<br />

54<br />

38<br />

11<br />

26<br />

42<br />

24<br />

10<br />

1<br />

54<br />

28<br />

21<br />

61<br />

42<br />

101<br />

2<br />

83<br />

20<br />

102<br />

1<br />

61<br />

34<br />

8<br />

56<br />

47<br />

101<br />

2<br />

69.3<br />

62.7<br />

50.0<br />

60.6<br />

63.2<br />

70.0<br />

68.8<br />

87.5<br />

70.5<br />

57.6<br />

58.8<br />

65.3<br />

66.1<br />

65.9<br />

50.0<br />

63.1<br />

73.3<br />

65.4<br />

80.0<br />

63.3<br />

70.9<br />

52.9<br />

69.9<br />

58.8<br />

65.5<br />

71.4<br />

0.148<br />

0.469<br />

0.088<br />

0.986<br />

0.893<br />

0.140<br />

0.837<br />

0.213<br />

0.065<br />

1.000


52<br />

4.1.2 Results <strong>from</strong> bulk <strong>milk</strong> samples<br />

Two parallel bulk <strong>milk</strong> samples were taken <strong>from</strong> each farm in the time <strong>of</strong><br />

sampling visits. Totally, ten bulk <strong>milk</strong> samples were collected <strong>from</strong> each farm (five<br />

samples, double), therefore there were 30 bulk <strong>milk</strong> samples as a total. General farm,<br />

<strong>milk</strong>ing and management practices information was also collected by the investigator<br />

during farm visits. General characteristics <strong>of</strong> farms are summarized in Table 19.<br />

Based on data in Table 19, it could be summarized that generally all sampling<br />

farms had qualitatively similar characteristics in farm management and <strong>milk</strong>ing<br />

practices. This was supported also by the data regarding counts and prevalence <strong>of</strong><br />

indicator bacteria <strong>of</strong> bulk <strong>milk</strong> samples among farms (Table 20 and 21).<br />

Table 19: Summary <strong>of</strong> general characteristics <strong>of</strong> sampling farms<br />

No. Factors Level Farm<br />

1<br />

1. Farm location <strong>from</strong> Close<br />

√<br />

residence area Medium<br />

Far<br />

Farms<br />

Farm<br />

2<br />

√<br />

Farm<br />

3<br />

2. Herd size Heads 200 400 600<br />

3. Stocking density Low (≥2)<br />

(m 2 /animal) Medium (1.5) √ √ √<br />

High (1)<br />

4. Number <strong>of</strong> workers Person 5 6 8<br />

5. Animal housing On the ground<br />

Elevated √ √ √<br />

6. Type <strong>of</strong> house Loose housing<br />

Pen √ √ √<br />

7. House for lactating Yes<br />

√ √ √<br />

<strong>goat</strong><br />

No<br />

8. Ventilation Poor<br />

Good √ √ √<br />

9. House surface Bamboo<br />

Wood √ √ √<br />

10. Surface condition Clean<br />

Medium<br />

Dirty<br />

11. Hygiene status Poor<br />

Good √ √<br />

√<br />

√<br />

√<br />

√<br />


53<br />

Farms<br />

No. Factors Level Farm<br />

1<br />

Farm<br />

2<br />

Farm<br />

3<br />

12. Special worker for<br />

<strong>milk</strong>ing<br />

Yes<br />

No<br />

√ √ √<br />

13. Hand washing<br />

before <strong>milk</strong>ing<br />

Yes<br />

No<br />

√ √ √<br />

14. Worker hygiene Poor<br />

√ √ √<br />

status<br />

Good<br />

15. Water source Tap<br />

Well √ √ √<br />

16. Water/chlorinate Yes<br />

No √ √ √<br />

17. Water/storage Close<br />

√ √ √<br />

Open<br />

18. Animal/<strong>milk</strong>ing Hand<br />

√ √ √<br />

technique<br />

Machine<br />

19. Animal/special<br />

place for <strong>milk</strong>ing<br />

Yes<br />

No<br />

√<br />

√<br />

√<br />

20. Animal/frequency<br />

<strong>of</strong> <strong>milk</strong>ing (per day)<br />

Once<br />

Twice<br />

√ √ √<br />

More<br />

21. Pre-<strong>milk</strong>ing Yes<br />

√ √ √<br />

washing <strong>of</strong> udder No<br />

22. Pre-<strong>milk</strong>ing drying<br />

<strong>of</strong> udder<br />

Yes<br />

No √ √ √<br />

23. Pre-dipping <strong>of</strong> teat Yes<br />

No √ √ √<br />

24. Fore-stripping Yes<br />

√ √ √<br />

No<br />

25. Post-dipping <strong>of</strong><br />

udder<br />

Yes<br />

No √ √ √<br />

26. Other animal Yes<br />

√ √ √<br />

species in the farm No<br />

Note: For a detailed description <strong>of</strong> every factor and level, please refer to Appendix A


54<br />

Table 20: Selected statistical value <strong>of</strong> indicator bacterial counts <strong>from</strong> bulk <strong>milk</strong><br />

samples (n=10/farm)<br />

No.<br />

Indicator<br />

Bacteria<br />

1. Total Plate<br />

Count (TPC)<br />

2. Coliforms<br />

3. Staphylococcus<br />

spp.<br />

4. Coagulase<br />

Positive<br />

Staphylococci<br />

Selected<br />

Statistical<br />

Value<br />

Overall<br />

[n=30]<br />

Farm<br />

1<br />

log cfu/ml<br />

Farm<br />

2<br />

Farm<br />

3<br />

Median 5.69 5.48 6.91 5.51<br />

Maximum 7.50 7.00 7.50 6.98<br />

Minimum 3.74 4.34 3.95 3.74<br />

IQR 1.85 1.82 1.35 0.96<br />

Median 2.98 3.49 3.34 2.24<br />

Maximum 4.45 4.45 3.54 3.02<br />

Minimum 0.70 0.70 0.70 0.70<br />

IQR 1.48 1.85 0.97 0.76<br />

Median 3.86 4.10 4.09 3.55<br />

Maximum 5.65 4.92 5.65 4.48<br />

Minimum 1.70 3.13 1.70 3.00<br />

IQR 1.08 1.15 1.00 0.65<br />

Median 3.66 4.05 3.76 3.41<br />

Maximum 5.65 4.83 5.65 3.86<br />

Minimum 1.70 1.70 1.70 1.70<br />

(CPS) IQR 2.10 1.58 2.84 1.13<br />

Median 3.32 3.30 3.60 3.17<br />

Maximum 5.54 4.23 5.54 4.52<br />

Minimum 1.70 1.70 1.70 1.70<br />

5. Coagulase<br />

Negative<br />

Staphylococci<br />

(CNS) IQR 0.79 0.60 1.00 1.22<br />

P-value<br />

(among<br />

farms)<br />

0.059<br />

0.040<br />

0.068<br />

0.275<br />

0.638<br />

Table 20 shows some selected statistical values for indicator bacterial counts<br />

<strong>from</strong> bulk <strong>milk</strong> samples. Coliforms counts differed significantly (P


55<br />

S. aureus in the European standard (EC, 1992) and German “Milchverordnung”<br />

(BGBl, 2004).<br />

Indicator bacteria<br />

CNS<br />

CPS<br />

Staphylococcus spp.<br />

Coliforms<br />

TPC<br />

3.32<br />

3.66<br />

3.86<br />

2.98<br />

5.69<br />

0 1 2 3 4 5 6<br />

Median Value (log cfu/ml)<br />

Figure 8: Bar charts <strong>of</strong> median values <strong>of</strong> indicator bacterial counts <strong>from</strong> overall bulk<br />

<strong>milk</strong> samples (n=30)<br />

Table 21 shows the proportion <strong>of</strong> positive samples <strong>of</strong> indicator bacteria <strong>from</strong><br />

bulk <strong>milk</strong> samples. The overall prevalence <strong>of</strong> coliforms, Staphylococcus spp., CPS<br />

and CNS were 86.7, 96.7, 76.7, and 86.7%, respectively. No statistically significant<br />

difference was observed among prevalence <strong>of</strong> each indicator bacteria within the farm<br />

level.<br />

Table 21: Proportion <strong>of</strong> positive samples <strong>of</strong> indicator bacteria <strong>from</strong> bulk <strong>milk</strong><br />

samples (n=10/farm)<br />

Indicator<br />

Bacteria<br />

Factor/level<br />

n<br />

No. <strong>of</strong><br />

positive/contaminated<br />

samples<br />

Percent <strong>of</strong><br />

positive<br />

samples<br />

Coliform Overall 30 26 86.7<br />

By Farm<br />

- Farm 1<br />

- Farm 2<br />

- Farm 3<br />

10<br />

10<br />

10<br />

9<br />

8<br />

9<br />

90<br />

80<br />

90<br />

Staphylococcus<br />

spp.<br />

Overall 30 29 96.7<br />

P-value<br />

0.749


56<br />

Indicator<br />

Bacteria<br />

Factor/level<br />

By Farm<br />

- Farm 1<br />

- Farm 2<br />

- Farm 3<br />

n<br />

10<br />

10<br />

10<br />

No. <strong>of</strong><br />

positive/contaminated<br />

samples<br />

10<br />

9<br />

10<br />

Percent <strong>of</strong><br />

positive<br />

samples<br />

100<br />

90<br />

100<br />

CPS Overall 30 23 76.7<br />

By Farm<br />

- Farm 1<br />

- Farm 2<br />

- Farm 3<br />

10<br />

10<br />

10<br />

8<br />

7<br />

8<br />

80<br />

70<br />

80<br />

CNS Overall 30 26 86.7<br />

By Farm<br />

- Farm 1<br />

- Farm 2<br />

- Farm 3<br />

10<br />

10<br />

10<br />

9<br />

8<br />

9<br />

90<br />

80<br />

90<br />

P-value<br />

0.355<br />

0.830<br />

0.749<br />

4.2 The comparison <strong>of</strong> indicator bacterial counts and prevalence between left<br />

and right udder <strong>milk</strong> samples<br />

Data for the indicator bacterial counts and prevalence in each udder half (left<br />

and right) <strong>milk</strong> samples are presented in Table 22 and Table 23, respectively. No<br />

statistically significant difference was observed either for indicator bacterial counts or<br />

prevalence between left and right udder <strong>milk</strong> samples.<br />

Table 22: Selected statistical value <strong>of</strong> indicator bacterial counts <strong>from</strong> left and right<br />

udder <strong>milk</strong> samples (n=150/udder half)<br />

No.<br />

Indicator Bacteria<br />

1. Total Plate Count<br />

(TPC)<br />

2. Coliforms<br />

Selected<br />

Statistical<br />

Value<br />

Left<br />

Udder<br />

Right<br />

Udder<br />

Log cfu/ml<br />

Median 3.86 3.59<br />

Maximum 6.96 6.85<br />

Minimum 1.00 0.70<br />

IQR 1.77 1.60<br />

Median 0.70 0.70<br />

Maximum 5.99 4.41<br />

Minimum 0.70 0.70<br />

IQR 1.56 1.30<br />

P-value<br />

0.267<br />

0.217


57<br />

No.<br />

Indicator Bacteria<br />

3. Staphylococcus<br />

spp.<br />

4. Coagulase Positive<br />

Staphylococci<br />

(CPS)<br />

5. Coagulase Negative<br />

Staphylococci<br />

(CNS)<br />

Selected<br />

Statistical<br />

Value<br />

Left<br />

Udder<br />

Right<br />

Udder<br />

Log cfu/ml<br />

Median 2.98 3.02<br />

Maximum 6.10 6.51<br />

Minimum 1.70 1.70<br />

IQR 2.03 2.11<br />

Median 1.70 1.70<br />

Maximum 6.02 6.18<br />

Minimum 1.70 1.70<br />

IQR 1.52 1.25<br />

Median 2.54 2.52<br />

Maximum 5.39 6.41<br />

Minimum 1.70 1.70<br />

IQR 1.87 2.16<br />

P-value<br />

0.740<br />

0.483<br />

0.499<br />

Table 23: Proportion <strong>of</strong> positive samples <strong>of</strong> indicator bacteria <strong>from</strong> left and right<br />

udder <strong>milk</strong> samples<br />

Indicator Bacteria Udder n<br />

Coliform<br />

Staphylococcus<br />

spp.<br />

CPS<br />

CNS<br />

- Left<br />

- Right<br />

- Left<br />

- Right<br />

- Left<br />

- Right<br />

- Left<br />

- Right<br />

150<br />

150<br />

150<br />

150<br />

150<br />

150<br />

150<br />

150<br />

No. <strong>of</strong><br />

positive/contaminated<br />

samples<br />

73<br />

66<br />

119<br />

117<br />

59<br />

54<br />

98<br />

99<br />

Prevalence<br />

(%)<br />

48.7<br />

44.0<br />

79.3<br />

78.0<br />

39.3<br />

36.0<br />

65.3<br />

66.0<br />

P-value<br />

0.487<br />

0.888<br />

0.634<br />

1.000<br />

4.3 The comparison between California mastitis test results and conventional<br />

bacteriological isolation<br />

Table 24 shows the comparison between CMT results (positive and negative)<br />

and conventional bacteriological isolation results by using McNemar’s test.<br />

McNemar’s Chi-square test was used to test the null hypothesis that the true


58<br />

proportions <strong>of</strong> successes (positive results) using the two methods in the same sample<br />

were equal (Petrie and Watson, 1999). The isolation <strong>of</strong> indicator bacteria by using<br />

conventional bacteriological methods was considered a gold standard. Further<br />

epidemiological and statistical analyses were done by calculating sensitivity,<br />

specificity for CMT as well as calculating Cohen’s kappa coefficient (κ) for<br />

measuring agreement between results <strong>of</strong> the two diagnostic tests/methods.<br />

Statistically significant differences (P


59<br />

Cohen’s kappa coefficient interpretation <strong>of</strong> agreement between two tests (Petrie and<br />

Watson, 1999):<br />

• “Poor” if κ ≤ 0.20;<br />

• “Fair” if 0.21 ≤ κ ≤ 0.40;<br />

• “Moderate” if 0.41 ≤ κ ≤ 0.60;<br />

• “Substantial” if 0.61 ≤ κ ≤ 0.80;<br />

• “Good” if κ exceeds 0.80


5. DISCUSSION AND CONCLUSIONS<br />

5.1 Discussion<br />

The objective <strong>of</strong> this study was to determine out the <strong>microbiological</strong> status<br />

(quantitatively and qualitatively) <strong>of</strong> <strong>raw</strong> <strong>goat</strong> <strong>milk</strong> and some potential risk factors<br />

associated with it, <strong>from</strong> <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms in Indonesia. Despite <strong>of</strong> a<br />

limited sampling location, which include only three <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms<br />

located in the Bogor District, West Java Province, it was likely that the results <strong>of</strong> this<br />

study would be useful to show some real data about the present situation <strong>of</strong> the<br />

<strong>microbiological</strong> status <strong>of</strong> <strong>goat</strong> <strong>milk</strong> in Indonesia. This was due to the fact that in<br />

Indonesia, <strong>dairy</strong> <strong>goat</strong> farms were concentrated in the West and Central Java Provinces<br />

and some other farms located in other provinces located on Java Island. Therefore the<br />

majority <strong>of</strong> the <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms had approximately similar general<br />

characteristics <strong>of</strong> the management and <strong>milk</strong>ing practices.<br />

It should be noted also that the <strong>milk</strong> produced <strong>from</strong> all sampling farms within<br />

this study, as well as <strong>from</strong> other <strong>dairy</strong> <strong>goat</strong> farms, was sold and consumed in <strong>raw</strong><br />

condition by the consumers. Moreover, in Indonesia, the consumers preferred to<br />

consume the <strong>goat</strong> <strong>milk</strong> as fresh as possible, since they consider the <strong>milk</strong> to be fresher<br />

when they can consume it as soon as the <strong>milk</strong> is secreted <strong>from</strong> the <strong>goat</strong> udder.<br />

Here, data on the counts and prevalence <strong>of</strong> indicator bacteria for the<br />

<strong>microbiological</strong> status <strong>of</strong> <strong>raw</strong> <strong>goat</strong> <strong>milk</strong> and also some potential risk factors associated<br />

with were obtained.<br />

5.1.1 Quantitative data<br />

There were 300 udder-half <strong>milk</strong> samples as the main sample and 30 bulk <strong>milk</strong><br />

samples as a supporting sample collected <strong>from</strong> three <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms<br />

with intensive breeding systems in the Bogor District, West Java Province, Indonesia.<br />

The samples were examined for the counts and presence <strong>of</strong> indicator bacteria, which


61<br />

were TPC, coliforms, Staphylococcus spp., CPS and CNS. The information regarding<br />

some potential risk factors, which was predicted to have association with the indicator<br />

bacteria, was also assessed.<br />

In this study the median values <strong>of</strong> indicator bacterial counts <strong>from</strong> overall<br />

udder-half <strong>milk</strong> samples were 3.74, 0.70, 3.00, 1.70 and 2.52 log cfu/ml for TPC,<br />

coliforms, Staphylococcus spp., CPS and CNS, respectively. Median values <strong>of</strong><br />

indicator bacterial counts <strong>from</strong> overall bulk <strong>milk</strong> samples were 5.69, 2.98, 3.86, 3.66<br />

and 3.32 log cfu/ml for for TPC, coliforms, Staphylococcus spp., CPS and CNS,<br />

respectively.<br />

Study or <strong>investigation</strong> reports regarding counts <strong>of</strong> bacteria in <strong>goat</strong> <strong>milk</strong> were<br />

very limited as compared to cow <strong>milk</strong>, and mostly concerned about proportion or<br />

prevalence <strong>of</strong> these bacteria. There was also no study/<strong>investigation</strong> report found in<br />

Indonesia regarding counts and prevalence <strong>of</strong> indicator bacteria in <strong>raw</strong> <strong>goat</strong> <strong>milk</strong> and<br />

potential risk factors associated with it.<br />

This was due to the fact that <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms in Indonesia just<br />

emerged about 10 – 15 years ago. In the past, <strong>goat</strong> <strong>milk</strong> was produced <strong>from</strong> backyard<br />

farming systems with a small number <strong>of</strong> animals. Today, the <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong><br />

farms have <strong>from</strong>100 to a thousand animals per farm.<br />

The median <strong>of</strong> the TPC <strong>of</strong> overall udder-half <strong>milk</strong> samples in this study (3.74<br />

log cfu/ml) was lower compared to the findings reported by Delgado-Pertinez et al.<br />

(2003) and Kyozaire et al. (2005). Delgado-Pertinez et al. (2003) reported that they<br />

collected udder-half <strong>goat</strong> <strong>milk</strong> samples <strong>from</strong> 28 farms in Spain and the mean value <strong>of</strong><br />

TPC <strong>from</strong> those samples was 4.81 log cfu/ml. Whereas the mean values <strong>of</strong> TPC <strong>of</strong><br />

270 udder halves <strong>milk</strong> samples collected <strong>from</strong> 3 <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms which<br />

were using bucket <strong>milk</strong>ing machine, pipeline <strong>milk</strong>ing machine and hand <strong>milk</strong>ing<br />

machine in South Africa were 4.21, 4.56 and 4.68 log cfu/ml, respectively (Kyozaire<br />

et al., 2005).


62<br />

Other studies conducted in Switzerland and the USA reported lower TPC <strong>of</strong><br />

bulk <strong>milk</strong> samples than here (5.69 log cfu/ml): the median <strong>of</strong> TPC <strong>of</strong> 344 bulk <strong>milk</strong><br />

samples <strong>from</strong> three <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms in Switzerland was 4.68 log cfu/ml<br />

(Muehlherr et al., 2003; Zweifel et al., 2005), whereas the mean <strong>of</strong> TPC <strong>of</strong> bulk <strong>milk</strong><br />

samples <strong>from</strong> three <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms located in Arkansas and Oklahoma<br />

USA was 2.95 log cfu/ml (Zeng and Escobar, 1996).<br />

The results <strong>of</strong> this study for the bulk <strong>milk</strong> samples were relatively higher as<br />

compared to the following findings: Morgan et al. (2003) collected bulk <strong>milk</strong> samples<br />

<strong>from</strong> intensive breeding systems <strong>of</strong> small and medium scale <strong>dairy</strong> <strong>goat</strong> farms in<br />

France. The mean values <strong>of</strong> <strong>goat</strong> <strong>milk</strong> <strong>from</strong> those farms in France were 5.03, 2.15 and<br />

2.44 log cfu/ml for TPC, coliforms and Staphylococcus spp. (CPS and CNS),<br />

respectively. Another finding was reported by Foschino et al. (2002), who collected<br />

60 bulk <strong>milk</strong> samples <strong>from</strong> 10 <strong>dairy</strong> <strong>goat</strong> farms during a six month period in Italy.<br />

The mean values <strong>of</strong> TPC, coliforms, S. aureus and CNS <strong>of</strong> Italian <strong>raw</strong> <strong>goat</strong> <strong>milk</strong><br />

samples were 4.70, 2.96, 3.07 and 3.11 log cfu/ml, respectively.<br />

However, these study results were relatively lower compared to the finding<br />

which was also reported by Morgan et al. (2003) <strong>from</strong> small and medium scale <strong>dairy</strong><br />

<strong>goat</strong> farms under extensive breeding systems in Greece and Portugal. They reported<br />

that mean values <strong>of</strong> indicator bacteria in <strong>goat</strong> bulk <strong>milk</strong> in Greece and Portugal were<br />

TPC = 7.5 and 7.6 log cfu/ml; coliforms = 6.25 and 6.39 log cfu/ml; Staphylococcus<br />

spp. = 5.23 and 4.28 log cfu/ml, respectively. The results <strong>of</strong> CNS counts here were<br />

also comparable to the finding <strong>of</strong> CNS counts in three <strong>commercial</strong> <strong>milk</strong>ing <strong>goat</strong> herds<br />

in the UK by Hall and Rycr<strong>of</strong>t (2007), which ranged <strong>from</strong> 3.00 to 5.08 log cfu/ml.<br />

This study result <strong>of</strong> coliform counts was comparable to the finding reported by<br />

Little and de Luvois (1999), who did a pilot study to determine <strong>microbiological</strong><br />

quality <strong>of</strong> unpasteurized <strong>milk</strong> <strong>from</strong> <strong>goat</strong> and sheep taken along the food chain in<br />

England and Wales, UK. They found that 11 out <strong>of</strong> 100 unpasteurized <strong>goat</strong> <strong>milk</strong><br />

samples had coliform counts <strong>of</strong> more than 2 log cfu/ml, whereas 38 samples contained<br />

coliform counts less than 2 log cfu/ml and no coliforms were detected in the rest <strong>of</strong><br />

the samples.


63<br />

Little and de Luvois (1999) also found that 15 out <strong>of</strong> 100 unpasteurized <strong>goat</strong><br />

<strong>milk</strong> samples were S. aureus positive and 6 out <strong>of</strong> 15 samples had S. aureus counts <strong>of</strong><br />

more than 2 log cfu/ml.<br />

The indicator bacterial counts <strong>from</strong> udder-half <strong>milk</strong> samples were significantly<br />

different (P


64<br />

(2005) in Switzerland, which found that the median <strong>of</strong> TPC was not significantly<br />

different among breeds <strong>of</strong> <strong>goat</strong>s.<br />

In the parity factor, the indicator bacteria counts, except for coliforms, were<br />

significantly different among parity levels. TPC, Staphylococcus spp., CPS and CNS<br />

counts tended to increase as the does got older. Only for Staphylococcus spp. group<br />

bacterial counts, the statistically significant differences were observed among<br />

lactation stages.<br />

Counts <strong>of</strong> indicator bacteria, except for coliforms, based on the teat end<br />

condition were observed to have statistically significant differences, in which normal<br />

teat ends had significantly lower counts <strong>of</strong> bacteria compared to teat ends with a<br />

smooth rough ring form. A similar pattern was found for the teat shape condition and<br />

udder inflammation status. In the teat shape condition, only the TPC showed a<br />

statistically significant difference. The TPC was significantly increased as the teat<br />

shape condition was more dilated, whereas in the normal udder, the counts <strong>of</strong><br />

indicator bacteria except for coliforms had significantly lower counts compared to the<br />

udder with inflammation.<br />

In the factor <strong>of</strong> <strong>milk</strong> appearance, indicator bacterial counts were not<br />

significantly different between the normal and abnormal <strong>milk</strong> appearance, except for<br />

TPC. TPC was significantly higher in the abnormal <strong>milk</strong> appearance than the normal<br />

one.<br />

5.1.2 Qualitative data<br />

Overall prevalence <strong>of</strong> coliforms, Staphylococcus spp., CPS and CNS <strong>from</strong><br />

udder-half <strong>milk</strong> samples were 46.3, 78.7, 37.7 and 66.0%, respectively and <strong>from</strong> bulk<br />

<strong>milk</strong> samples were 86.7, 96.7, 76.7, and 86.7%, respectively.<br />

In the udder-half <strong>milk</strong> samples, statistically significant difference was<br />

observed only for prevalence <strong>of</strong> coliforms and CNS among farms, whereas in bulk<br />

<strong>milk</strong> samples no statistically significant difference was observed among prevalence <strong>of</strong><br />

indicator bacteria within farm level.


65<br />

The prevalence <strong>of</strong> coliforms in these study results, either <strong>from</strong> udder-half or<br />

bulk <strong>milk</strong> samples, were higher compared to a study result <strong>of</strong> coliform prevalence in<br />

unpasteurized <strong>goat</strong> <strong>milk</strong> in England and Wales, UK by Little and de Luvois (1999).<br />

They reported that the prevalence <strong>of</strong> coliforms was 12%. However within the farm<br />

level, farm 1 had a lower prevalence <strong>of</strong> Coliforms with only 6% in the udder-half <strong>milk</strong><br />

samples.<br />

Prevalence <strong>of</strong> Staphylococcus spp. both <strong>from</strong> udder-half and bulk <strong>milk</strong><br />

samples <strong>from</strong> this study were higher to the prevalence <strong>of</strong> these bacteria reported in the<br />

previous reports <strong>from</strong> other countries by Kalogridou-Vassiliadou (1991); Contreras et<br />

al. (1995); White and Hinckley (1999); Sanchez et al. (1999); Ndegwa et al. (2001);<br />

Leitner et al. (2004); Moroni et al. (2005b) and Leitner et al. (2007), which were 3.1<br />

(Greece), 4.1 (Italy), 38.2 (USA), 70.0 (Spain), 60.3 (Kenya), 32.9 (Israel), 1.6 (Italy)<br />

and 28.8% (Israel), respectively.<br />

However the prevalence <strong>of</strong> Staphylococcus spp. in the bulk <strong>milk</strong> samples<br />

found here was comparable to the study results reported by Contreras et al. (1999).<br />

They examined bulk tank <strong>milk</strong> <strong>from</strong> <strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong>s in Maryland, USA and it<br />

was found that most <strong>of</strong> the pathogen isolated was Staphylococcus spp. with 95.7% <strong>of</strong><br />

prevalence.<br />

As reported by many others studies, this study also recorded CNS as the most<br />

prevalent pathogens within Staphylococcus spp. Staphylococcus spp. is the most<br />

prevalent pathogen responsible for IMI in small ruminants and CNS is the most<br />

prevalent one within this group <strong>of</strong> bacteria (Contreras et al., 2007). Although less<br />

pathogenic than S. aureus, CNS can also produce persistent subclinical mastitis,<br />

significantly increase MSCC and cause clinical mastitis (Deinh<strong>of</strong>er and Pernthaner,<br />

1995; Contreras et al., 1997).<br />

Most studies on the IMI estimated the prevalence by halves and not by<br />

animals because the half is an anatomically independent unit (Sanchez et al., 1999).


66<br />

In this study 64.7% (97/150) <strong>of</strong> <strong>goat</strong>s had infections in both <strong>of</strong> their udders<br />

(positive bacteriological isolation <strong>of</strong> Staphylococcus spp.) and it was found also that<br />

the counts and prevalence <strong>of</strong> indicator bacteria were not observed to have statistically<br />

significant differences between samples <strong>from</strong> left and right udders (Table 20 and 21).<br />

The results <strong>of</strong> this study showed that the CNS prevalence was higher<br />

compared to CPS. The CNS and CPS prevalence <strong>from</strong> udder-half <strong>milk</strong> samples were<br />

66 and 37.7%, respectively.<br />

Following studies reported to have lower CNS and CPS prevalence <strong>of</strong> udderhalf<br />

<strong>goat</strong> <strong>milk</strong> samples than here: 44.5 and 17.2%, respectively in Greece<br />

(Kalogridou-Vassiliadou, 1991); 61.1 and 18.5%, respectively in Greece (Boscos et<br />

al., 1996), 9.6% in Ethiopia (Wakwoya et al., 2006); 17.9 % in Israel (Leitner et al.,<br />

2007) and 47% in UK (Hall and Rycr<strong>of</strong>t, 2007) (the last three data only for CNS).<br />

Whereas these following studies reported higher CNS prevalence compared to<br />

these study results: 76.1% in Austria (Deinh<strong>of</strong>er and Pernthaner, 1995); 71.4% in<br />

Spain (Contreras et al., 1997); 68.1% in USA (White and Hinckley, 1999).<br />

Comparable results were found <strong>from</strong> the study in <strong>dairy</strong> <strong>goat</strong> farms in Vermont, USA<br />

which reported 66.7% prevalence <strong>of</strong> CNS <strong>from</strong> udder-half <strong>milk</strong> samples taken in 40<br />

days after parturition (McDougall et al., 2002).<br />

5.1.2.1 The assessment <strong>of</strong> associations between sample prevalence <strong>of</strong> indicator<br />

bacteria and potential risk factors<br />

The evaluation <strong>of</strong> several potential risk factors in its association with the<br />

presence <strong>of</strong> indicator bacteria in the samples was shown in Tables 10 – 16. All<br />

potential risk factors were analyzed for the prevalence <strong>of</strong> each indicator bacteria both<br />

by univariate (Chi-square test) and by multivariate analysis <strong>of</strong> the logistic regression<br />

test. Multivariable analysis permits estimation <strong>of</strong> the real impact <strong>of</strong> a particular factor<br />

without interaction <strong>from</strong> other factors. The results show that some <strong>of</strong> those potential<br />

risk factors could be considered to be risk factors, which increased the risk <strong>of</strong><br />

presence <strong>of</strong> each indicator bacteria.


67<br />

Breed <strong>of</strong> <strong>goat</strong>s: these study results show that the breed <strong>of</strong> <strong>goat</strong>s was only<br />

significantly associated with the presence <strong>of</strong> coliforms in the samples, and the Saanen<br />

crossbreed had a significantly higher chance <strong>of</strong> coliform contamination (P


68<br />

evaluation by logistic regression showed that the lactation stage was not a risk factor<br />

for those bacteria (Table 13 and 15). Bergonier et al. (2003) stated that the incidence<br />

<strong>of</strong> clinical IMI did not vary with the lactation stage in the same way as in <strong>dairy</strong> cattle,<br />

on the contrary, higher rates were observed during the first third <strong>of</strong> lactation. This<br />

statement was in agreement with the results presented in Tables 13 and 15. Bergonier<br />

et al. (2003) also stated that the variations <strong>of</strong> subclinical IMI incidence according to<br />

the stage <strong>of</strong> lactation should be assessed by systematic, monthly <strong>milk</strong> culturing <strong>of</strong><br />

large numbers <strong>of</strong> healthy udders, and this kind <strong>of</strong> a study was very rare. However a<br />

finding reported by Moroni et al. (2005b) was contrary to this study result. They<br />

concluded that later stages <strong>of</strong> lactation had more infection than earlier lactation stages.<br />

Udder inflammation status: another potential risk factor, which was found to<br />

have a positive association with indicator bacteria, was the udder inflammation status.<br />

The status <strong>of</strong> udder inflammation was based on a CMT score by following the method<br />

suggested by Wakwoya et al. (2006). Udder inflammation status was found to have a<br />

significant association with the presence <strong>of</strong> Staphylococcus spp. and CPS. Moreover<br />

results <strong>of</strong> logistic regression confirmed that the udder inflammation status was a risk<br />

factor for the presence <strong>of</strong> both bacteria in the <strong>milk</strong> samples. The udders with<br />

inflammation had a strong and significant association with and higher prevalence <strong>of</strong><br />

Staphylococcus spp. [OR= 2.490, P= 0.002, 95%CI= 1.403, 4.418] and CPS [OR=<br />

2.622, P= 0.001, 95%CI= 1.487, 4.623] compared to the udders without<br />

inflammation.<br />

None <strong>of</strong> the potential risk factors was significantly associated with the<br />

presence <strong>of</strong> CNS in the samples, but as a member <strong>of</strong> Staphylococcus spp. and despite<br />

<strong>of</strong> statistical insignificancy, numerical prevalence <strong>of</strong> CNS in the udder with<br />

inflammation was higher than in the normal udder (Table 16). Therefore the udder<br />

inflammation status could be used as an indicator <strong>of</strong> the presence <strong>of</strong> CNS in the <strong>milk</strong><br />

samples.<br />

Other potential risk factors (udder symmetry, udder hygiene status, teat end<br />

condition, teat skin condition, teat shape and <strong>milk</strong> appearance) were found to have no<br />

statistically significant association with the presence <strong>of</strong> indicator bacteria in the


69<br />

samples either in univariate or multivariate analysis. Those potential risk factors were<br />

unrelated to indicator bacteria detection rates.<br />

5.1.3 California Mastitis Test results<br />

CMT was conducted on 300 udder-half <strong>milk</strong> samples for determining the<br />

udder inflammation status as well as for an indicator <strong>of</strong> the presence <strong>of</strong> subclinical<br />

mastitis or IMI. Regarding the CMT score, 62.7% (188/300) <strong>of</strong> the samples were<br />

CMT positive and 37.3% (112/300) <strong>of</strong> the samples were CMT negative. This result<br />

was different compared to the study result reported by Wakwoya et al. (2006) in<br />

Ethiopia, that showed <strong>from</strong> 680 udder-half <strong>goat</strong> <strong>milk</strong> samples, 278 (40.9%) <strong>milk</strong><br />

samples were CMT positive, while 402 (59.1%) samples were CMT negative. On the<br />

other hand, 28 (10.1%) <strong>of</strong> the 278 CMT positive <strong>milk</strong> samples yielded no bacterial<br />

growth while the remaining 250 (89.9%) samples were also culture positive in which<br />

diverse bacterial pathogens were identified. They did not present a further proportion<br />

<strong>of</strong> the bacteria growth in CMT positive-negative samples for each identified bacteria.<br />

In the isolation <strong>of</strong> indicator bacteria using conventional bacteriological<br />

isolation method, it was found that for coliforms 47.3% (89/188) <strong>of</strong> CMT positive<br />

samples yielded coliform growth, while the remaining 52.7% (99/188) <strong>of</strong> CMT<br />

positive samples yielded no coliform growth. On the other hand, 44.6% (50/112) <strong>of</strong><br />

the CMT negative samples yielded coliform growth and 55.4% (62/112) <strong>of</strong> the CMT<br />

negative samples yielded no bacterial growth.<br />

For the Staphylococcus spp., 84.0% (158/188) <strong>of</strong> CMT positive samples<br />

yielded bacterial growth and the rest [16.0% (30/188) <strong>of</strong> CMT positive samples]<br />

yielded no bacterial growth. Whereas 69.6% (78/112) <strong>of</strong> CMT negative samples<br />

yielded bacterial growth and the rest [30.4% (34/112)] yielded no growth.<br />

In CPS, 44.1% (83/188) <strong>of</strong> CMT positive samples yielded bacterial growth<br />

and the remaining 55.9% (105/188) yielded no bacterial growth. In CMT negative<br />

samples, 26.8% (30/112) yielded bacterial growth and for the rest <strong>of</strong> the samples<br />

(73.2% (82/112)) yielded no growth <strong>of</strong> bacteria.


70<br />

For CNS, 69.68% (131/188) <strong>of</strong> CMT positive samples yielded bacteria growth<br />

and the remaining 30.32% (57/188) <strong>of</strong> the samples yielded no growth <strong>of</strong> bacteria. In<br />

CMT negative samples, 59.82% (67/112) yielded bacterial growth, whereas 40.18%<br />

(45/112) <strong>of</strong> the remaining samples yielded no growth <strong>of</strong> bacteria.<br />

The study results showed that except in coliforms and CPS, the proportion <strong>of</strong><br />

CMT positive samples which yielded bacterial growth was higher compared to CMT<br />

positive samples with no bacterial growth. Wakwoya et al. (2006) explained that the<br />

CMT positive and culture negative samples (those which yielded no bacterial growth)<br />

could be partly explained in that the udder could be injured and was recovering <strong>from</strong><br />

infection or the infection could be not due to a bacterial pathogen. It could also be<br />

due to an organism such as mycoplasma, which requires special media and cannot be<br />

detected using routine bacterial isolation techniques.<br />

The proportion <strong>of</strong> CMT negative samples that yielded bacterial growth in each<br />

indicator bacteria, except for CPS, in this study was relatively higher than a report<br />

<strong>from</strong> Wakwoya et al. (2006). They found that <strong>from</strong> a total <strong>of</strong> 402 <strong>milk</strong> samples taken<br />

as CMT negative, 124 (30.8%) yielded bacterial growth on cultures. This study result<br />

was also higher compared to the study results in Kenya by Ndegwa et al. (2000), who<br />

reported that 22.5% <strong>of</strong> 568 CMT negative samples yielded bacterial growth. They<br />

suggested that bacterial organisms isolated <strong>from</strong> the CMT negative samples were<br />

either a latent cause <strong>of</strong> infections or did not stimulate any significant increase in<br />

somatic cell counts.<br />

McNemar Chi-square test results showed that statistically significant<br />

differences (P


71<br />

The results were comparable with findings by Ndegwa et al. (2000), who<br />

reported no significant direct relationship between bacterial isolation and CMT in<br />

<strong>goat</strong> <strong>milk</strong> <strong>from</strong> <strong>dairy</strong> <strong>goat</strong> farms in Kenya; Winter and Baumgartner (1999) reported<br />

<strong>from</strong> their study results in Austria regarding the evaluation <strong>of</strong> CMT reaction in <strong>goat</strong><br />

<strong>milk</strong>, that CMT was not specific for infected udder halves, but can be used as an<br />

additional diagnostic tool concerning <strong>goat</strong> mastitis without overestimation, due to the<br />

influence <strong>of</strong> different factors in cell counts.<br />

Another previous report was comparable to the result here, Schaeren and<br />

Maurer (2006) had evaluated the relationship <strong>of</strong> subclinical udder infection and<br />

individual SCC as well as CMT in three <strong>dairy</strong> <strong>goat</strong> herds in Bern, Switzerland. They<br />

concluded that the relation between CMT reactions and udder infections was not very<br />

close. More than 20% <strong>of</strong> mammary halves infected with CNS showed negative CMT<br />

reactions. On the other hand, 25% <strong>of</strong> the samples <strong>from</strong> mammary halves without a<br />

proven infection reacted positively.<br />

However, these study results showed that despite <strong>of</strong> statistical significance,<br />

numerically the proportion <strong>of</strong> CMT positive samples which yielded bacterial growth<br />

was higher compared to CMT negative samples which yielded bacterial growth in all<br />

indicator bacteria.<br />

McDougall et al. (2001) stated that definite detection <strong>of</strong> infected animals relies<br />

on the positive culture <strong>of</strong> pathogens <strong>from</strong> aseptically collected <strong>milk</strong> samples. However<br />

bacteriology has limitations due to the requirements for laboratory support, the time<br />

delays for culture to occur and the costs associated with the bacteriology assessment.<br />

Contreras et al. (1996), Perrin et al. (1997) and McDougall et al. (2001) stated that<br />

CMT is a subjective screening test based on scoring the degree <strong>of</strong> gel formation <strong>of</strong> a<br />

<strong>milk</strong> and bromocresol reagent mixture. The CMT score has been shown to be<br />

positively associated with SCC and with the probability <strong>of</strong> bacterial infection.<br />

McDougall et al. (2001) also stated that <strong>of</strong> the “animal side test” CMT was<br />

superior to other indirect test such as impedance. They concluded <strong>from</strong> their study<br />

that wide variation in the test characteristics <strong>of</strong> SCC, CMT and impedance were


72<br />

reported in sheep and <strong>goat</strong>. This was at least partly due to differences in the<br />

prevalence <strong>of</strong> infection within the population studied. Their study result showed the<br />

effect <strong>of</strong> changing prevalence on the test performances. Perrin et al. (1997) also<br />

suggested that CMT had to be used carefully for low <strong>milk</strong>-yield <strong>goat</strong>s or for late<br />

lactations.<br />

Furthermore Gonzalez-Rodriguez and Carmenes (1996) reported their study<br />

results about the accuracy <strong>of</strong> CMT that was higher when compared with SCC, but an<br />

increase <strong>of</strong> false-positive samples was observed toward the end <strong>of</strong> lactation, which<br />

also implied a decrease in the predictive value <strong>of</strong> positive results. They also concluded<br />

that samples taken in the last month prior to the dry therapy would have a high error<br />

rate in predicting infected glands. They suggested taking the samples in the second<br />

and third months after parturition. Constant CMT positive reactions should be<br />

submitted for bacteriological analysis.<br />

Based on these study results and the above mentioned previous reports, it<br />

could be stated that CMT can be used as an effective, reliable, cheap and “farm and<br />

farmer friendly test” for screen testing <strong>of</strong> IMI or subclinical mastitis in <strong>dairy</strong> <strong>goat</strong>s.<br />

5.2 Conclusions<br />

Three hundred udder halves and thirty bulk <strong>milk</strong> samples <strong>from</strong> three<br />

<strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> farms, in the Bogor District, West Java Province, Indonesia<br />

were investigated for counts and prevalence indicator bacteria, which were TPC,<br />

coliforms, Staphylococcus spp., CPS and CNS. Ten potential risk factors were also<br />

evaluated in relation to the counts and prevalence <strong>of</strong> indicator bacteria.<br />

The median values <strong>of</strong> the indicator bacterial counts <strong>from</strong> overall udder-half<br />

<strong>milk</strong> samples were 3.74, 0.70, 3.00, 1.70 and 2.52 log cfu/ml and <strong>from</strong> the bulk <strong>milk</strong><br />

samples 5.69, 2.98, 3.86, 3.65 and 3.32 log cfu/ml for TPC, coliforms, Staphylococcus<br />

spp., CPS and CNS, respectively.


73<br />

The indicator bacterial counts <strong>from</strong> udder-half <strong>milk</strong> samples were significantly<br />

different (P


74<br />

and higher risk <strong>of</strong> having CPS in the samples, and udders with inflammation, that had<br />

a strong significant association and a higher chance <strong>of</strong> having contaminated samples<br />

by Staphylococcus spp. or CPS, compared to udders without inflammation.<br />

No statistically significant difference was observed either for counts or<br />

prevalence <strong>of</strong> indicator bacteria between left and right udder <strong>milk</strong> samples.<br />

A statistically insignificant difference (P>0.05) between the CMT result and<br />

the bacterial isolation was only observed for CNS, but the agreement between the two<br />

test results was poor (κ = 0.100) and the CMT had moderate sensitivity (66%) and a<br />

relatively low specificity (44%). However, numerically, the proportion <strong>of</strong> CMT<br />

positive samples that yielded bacterial growth was higher compared to the CMT<br />

negative samples that yielded bacterial growth in all indicator bacteria. It was also<br />

supported by the fact that udder with inflammation, which was determined based on<br />

the CMT result, had been proved to have statistically significant higher results <strong>of</strong><br />

Staphylococcus spp. and CPS positive samples than udder without inflammation.<br />

Therefore CMT could be used as an effective, reliable, cheap and “farm and farmer<br />

friendly test” for screen testing <strong>of</strong> IMI or subclinical mastitis in <strong>dairy</strong> <strong>goat</strong>s.


REFERENCES<br />

Abou-Eleinin, A.A., Ryser, E.T., Donelly, C.W. (2000): Incidence and seasonal<br />

variation <strong>of</strong> Listeria species in bulk <strong>milk</strong> tank <strong>goat</strong>’s <strong>milk</strong>. J. Food Prot. 63<br />

(9), 1208-13.<br />

Adams, M.R., Moss, M.O. (2000): Food Microbiology. 2 nd Ed. The Royal Society <strong>of</strong><br />

Chemistry. Cambridge.<br />

Ameh, J.A., Tari, I.S. (2000): Observations on the prevalence <strong>of</strong> caprine mastitis in<br />

relation to predisposing factors in Maiduguri. Small Rumin. Res. 35, 1-5.<br />

Ariznabarreta, A., Gonzalo, C., San Primitivo, F. (2002): Microbiological quality and<br />

somatic cell count <strong>of</strong> ewe <strong>milk</strong> with special reference to staphylococci. J.<br />

Dairy Sci. 85, 1370–1375.<br />

Bean, N.H., Goulding, J.S., Lao, C., Angulo, F.J. (1996): Surveillance <strong>of</strong> foodborne<br />

disease outbreaks-United States, 1988-1992. Morbidity and Mortality Weekly<br />

Rep. 45 (SS-5), 1.<br />

Bergonier, D., De Cremoux, R., Rupp, R., Lagriffoul, G., Berthelot, X. (2003):<br />

Mastitis <strong>of</strong> <strong>dairy</strong> small ruminants. Vet. Res. 34, 689-716.<br />

BGBl (Bundesgesetzblatt). (2004): Milchverordnung - Verordnung über Hygieneund<br />

Qualitätsanforderungen an Milch und Erzeugnisse auf Milchbasis.<br />

Neugefasst durch Bek. v. 20. 7.2000 I 1178; zuletzt geändert durch Art. 5 V<br />

v. 9.11.2004 I 2791. Bundesministerium der Justiz, Bundesrepublik<br />

Deutschland.<br />

Boscos, C., Stefanakis, A., Alexopoulos, C., Samartzi, O. (1996): Prevalence <strong>of</strong><br />

subclinical mastitis and influence <strong>of</strong> breed, parity stage <strong>of</strong> lactation and<br />

mammary bacteriological status on coulter counts and California mastitis test<br />

in <strong>milk</strong> <strong>of</strong> Saanen and autochthonous <strong>goat</strong>s. Small Rumin. Res. 21, 139-147.<br />

BSN (Badan Standardisasi Nasional) (1998): Susu Segar. SNI 01-3141-1998. Jakarta.<br />

Chye, F.K., Abdullah, A., Ayob, M.K. (2004): Bacteriological quality and safety <strong>of</strong><br />

<strong>raw</strong> <strong>milk</strong> in Malaysia. Food Microbiol. 21, 535-541.<br />

Contreras, A., Corrales, J.C., Sierra, D., Marco, J. (1995): Prevalence and aetiology <strong>of</strong><br />

nonclinical intramammary infection in Murciano–Granadina <strong>goat</strong>s. Small<br />

Rumin. Res. 17, 71–78.


76<br />

Contreras, A., Sierra, D., Corrales, J.C., Sanchez, A., Marco, J. (1996): Physiological<br />

threshold <strong>of</strong> somatic cell count and California mastitis test for diagnosis <strong>of</strong><br />

caprine subclinical mastitis. Small Rumin. Res. 21, 259-264.<br />

Contreras, A., Corrales, J.C., Sanchez, A., Sierra, D. (1997): Persistence <strong>of</strong><br />

subclinical intramammary pathogens in <strong>goat</strong>s throughout lactation. J. Dairy<br />

Sci 80, 2815–2819.<br />

Contreras, A., Paape, M.J., Miller, R.H. (1999): Prevalence <strong>of</strong> subclinical<br />

intramammary infection caused by Staphylococcus epidermidis in a<br />

<strong>commercial</strong> <strong>dairy</strong> <strong>goat</strong> herd. Small Rumin. Res. 31, 203-208.<br />

Contreras, A., Sierra, D., Sanchez, A., Corrales, J.C., Marcoc, J.C., Paape, M.J.,<br />

Gonzalo, C. (2007): Mastitis in small ruminants. Small Rumin. Res. 68, 145–<br />

153.<br />

Dawson, B., Trapp, R.G. (2004): Basic and Clinical Biostatistics. 4 th ed. Mc G<strong>raw</strong><br />

Hill. International Edition.<br />

Deinh<strong>of</strong>er, M., Pernthaner, A. (1995): Staphylococcus spp. as mastitis-related<br />

pathogens in <strong>goat</strong> <strong>milk</strong>. Veterinary Microbiology 43, 161-166.<br />

Delgado-Pertinez, M., Alcalde, M.J.,Guzman-Guerrero, J.L., Castel, J.M., Mena, Y.,<br />

Caravaca, F. (2003): Effect <strong>of</strong> hygiene-sanitary management on <strong>goat</strong> <strong>milk</strong><br />

quality in semi-extensive systems in Spain. Small Rumin. Res. 47, 51–61.<br />

Devendra, C., Coop, I.E. (1982): Ecology and Distribution. In: I.E. Coop (Editor):<br />

World Animal Science C 1 Production System Approach: Sheep and Goat<br />

Production. Amsterdam: Elsevier. pp. 1-14.<br />

DGLS (Directorate General <strong>of</strong> Livestock) (2005): Livestock statistics <strong>of</strong> Indonesia.<br />

DGLS-Ministry <strong>of</strong> Agriculture, Republic <strong>of</strong> Indonesia.<br />

EFSA (European Food Safety Authority) (2005): Opinion on the usefulness <strong>of</strong><br />

somatic cell counts for safety <strong>of</strong> <strong>milk</strong> and <strong>milk</strong> derived products <strong>from</strong> <strong>goat</strong>s.<br />

EFSA Journal 305, 1-19.<br />

EC (European Council) (1992): EC Directive 92/46/EEC <strong>of</strong> 16 June 1992 laying<br />

down the health rules for the production and placing on the market <strong>of</strong> <strong>raw</strong><br />

<strong>milk</strong>, heat-treated <strong>milk</strong> and <strong>milk</strong>-based products. Luxembourg.<br />

FAO (Food and Agricultural Organization) (2002): Medium term projections for meat<br />

and <strong>dairy</strong> products to 2010. Committee on commodity problems.<br />

Intergovernmental group on meat and <strong>dairy</strong> products. 19 th session. Rome.<br />

[cited 2006 Aug 31]. Available <strong>from</strong>: http://www.fao.org/DOCREP/<br />

MEETING /004/Y7022E /y7022e00.htm.


77<br />

FAO (Food and Agricultural Organization) (2006): Major food and agricultural<br />

commodities and producers. Country by commodity. [cited 2006 Aug 25].<br />

Available <strong>from</strong>: http://www.fao.org/es/ess/top/commodity.html?lang=en&<br />

item=1020&year=2005.<br />

FDA (Food and Drug Administration) (2001): Aerobic Plate Count. Bacteriological<br />

Analytical Manual Online. US FDA CFSAN. [cited 2006 Aug 20].<br />

Available <strong>from</strong>: http://www.cfsan.fda.gov/~ebam/bam-3.html.<br />

Foschino, R., Invernizzi, A., Barucco, R., Stradiotto, K., (2002): Microbial<br />

composition, including the incidence <strong>of</strong> pathogens, <strong>of</strong> <strong>goat</strong> <strong>milk</strong> <strong>from</strong> the<br />

Bergamo region <strong>of</strong> Italy during a lactation year. J. Dairy Res. 69, 213–225.<br />

Galal, S. (2005): Biodiversity in <strong>goat</strong>s. Small Rumin. Res. 60, 75–81.<br />

Goldberg, J. J., Murdough, P.A., Howard, A.B., Drechsler, P.A., Pankey,J.W.,<br />

Ledbetter, G.A., Day, L.L., Day, J.D. (1994): Winter evaluation <strong>of</strong> a<br />

post<strong>milk</strong>ing powdered teat dip. J. Dairy Sci. 77: 748-758.<br />

Gonzalez-Rodriguez, M.C., Carmenes, P. (1996): Evaluation <strong>of</strong> the California<br />

mastitis test as a discriminant method to detect subclinical mastitis in ewes.<br />

Small Rumin. Res. 21, 245-250.<br />

Gonzalo, C., Carriedo, J.A., Beneitez, E., Juarez, M.T., De La Fuente, L.F., San<br />

Primitivo, F. (2006): Short communication: Bulk tank total bacterial count<br />

in <strong>dairy</strong> sheep: Factor <strong>of</strong> variation and relationship with somatic cell count.<br />

J. Dairy Sci. 89, 549-552.<br />

Haenlein, G.F.W. (2002): Relationship <strong>of</strong> somatic cell counts in <strong>goat</strong> <strong>milk</strong> to mastitis<br />

and productivity. Small Rumin. Res. 45, 163–178.<br />

Haenlein, G.F.W. (2004): Goat <strong>milk</strong> in human nutrition. Small Rumin. Res. 51, 155-<br />

163.<br />

Hall, S.M., Rycr<strong>of</strong>t, A.N. (2007): Causative organisms and somatic cell counts in<br />

subclinical intramammary infections in <strong>milk</strong>ing <strong>goat</strong>s in the UK. Vet. Rec.<br />

160, 19-22.<br />

Hillerton, J. E., Bramley, A. J., Staker, R. T., McKinnon, C. H. (1995): Patterns <strong>of</strong><br />

intramammary infection and clinical mastitis over a 5-year period in a closely<br />

monitored herd applying mastitis control measures. J. Dairy Res. 62, 39–50.<br />

ISO (International Organization for Standardization) 4832 (1991): International<br />

Standard: Microbiology – General guidance for the enumeration <strong>of</strong> coliforms<br />

– colony count technique. Geneve.


78<br />

ISO (International Organization for Standardization) 6887-1 (1999): International<br />

Standard: Microbiology <strong>of</strong> food and animal feeding stuffs – Preparation <strong>of</strong><br />

test samples, initial suspension and decimal dilutions for <strong>microbiological</strong><br />

examination - Part 1: General rules for the preparation <strong>of</strong> the initial<br />

suspension and decimal dilutions. Geneve.<br />

ISO (International Organization for Standardization) 6888-1 (1999): International<br />

Standard: Microbiology <strong>of</strong> food and animal feeding stuffs – horizontal<br />

method for the enumeration <strong>of</strong> coagulase-positive staphylococci<br />

(Staphylococcus aureus and other species). Part 2: Technique using Baird<br />

Parker agar medium. Geneve.<br />

ISO (International Organization for Standardization) 4833 (2003): International<br />

Standard: Microbiology <strong>of</strong> food and animal feeding stuffs – horizontal<br />

method for the enumeration <strong>of</strong> microorganisms – colony count technique at<br />

30 o C. Geneve.<br />

Jay, J.M., Loessner, M.J., Golden, D.A. (2005): Modern Food Microbiology. 7 th ed.<br />

New York: Springer.<br />

Jayarao, B.M., Wang, L. (1999): A study on the prevalence <strong>of</strong> Gram negative<br />

bacteria in bulk <strong>milk</strong> tank. J. Dairy Sci. 82, 2620-2624.<br />

Kalogridou-Vassiliadou, D. (1991): Mastitis-related pathogens in <strong>goat</strong> <strong>milk</strong>. Small<br />

Rumin. Res. 4, 203–212.<br />

Klinger, I., Rosenthal, I. (1997): Public health and the safety <strong>of</strong> <strong>milk</strong> and <strong>milk</strong><br />

products <strong>from</strong> sheep and <strong>goat</strong>s. Rev.sci.tech.Off.int Epiz.16 (2), 482-488.<br />

Knights, M., Garcia, G.W. (1997): The status and characteristics <strong>of</strong> the <strong>goat</strong> (Capra<br />

hircus) and its potential role as a significant <strong>milk</strong> producer in the tropics: A<br />

Review. Small Rumin. Res. 26, 203-215.<br />

Kyozaire, J.K., Veary, C.M., Petzer, I.M., Donkin, E.F. (2005): Microbiological<br />

quality <strong>of</strong> <strong>goat</strong>’s <strong>milk</strong> obtained under different production systems. J. S. Afr.<br />

Vet. Assoc. 76 (2), 69-73.<br />

Leitner, G., Merin, U., Silanikove, N. (2004): Changes in <strong>milk</strong> composition as<br />

affected by subclinical mastitis in <strong>goat</strong>s. J. Dairy Sci. 87, 1719–1726.<br />

Leitner, G., Merin, U., Lavi, Y., Egber, A., Silanikove, N. (2007): Aetiology <strong>of</strong><br />

intramammary infection and its effect on <strong>milk</strong> composition in <strong>goat</strong> flocks.<br />

Journal <strong>of</strong> Dairy Research 74, 186–193.<br />

Little, C.L., de Louvois, J. (1999): Health risks associated with unpasteurized <strong>goat</strong>s'<br />

and ewes' <strong>milk</strong> on retail sale in England and Wales. A PHLS Dairy Products<br />

Working Group Study. Epidemiol. Infect. 122, 403-408.


79<br />

McDougall, S., Murdough, P., Pankey, W., Delaney, C., Barlow, J., Scruton, D.<br />

(2001): Relationship among somatic cell count, California mastitis test,<br />

impedance and bacteriological status <strong>of</strong> <strong>milk</strong> in <strong>goat</strong>s and sheep in early<br />

lactation. Small Rumin. Res. 40, 245-254.<br />

McDougall, S., Pankey, W., Delaney, C., Barlow, J., Murdough, P.A., Scruton, D.<br />

(2002): Prevalence and incidence <strong>of</strong> subclinical mastitis in <strong>goat</strong>s and <strong>dairy</strong><br />

ewes in Vermont, USA. Small Rumin. Res. 46, 115–121.<br />

Mein, G. A., Neijenhuis, F., Morgan, W. F., Reinemann, D. J., Hillerton, J. E., Baines,<br />

J. R., Ohnstad, I., Rasmussen, M. D., Timms, L., Britt, J. S., Farnsworth, R.,<br />

Cook, N., Hemling, T. (2001): Evaluation <strong>of</strong> bovine teat condition in<br />

<strong>commercial</strong> <strong>dairy</strong> herds: 1. Non-infectious factors. Pages 347–351 in Proc.<br />

2nd Int. Symp. on Mastitis and Milk Quality, Vancouver, BC, Canada.<br />

Meyrand, A., Montet, M.P., Bavai, C., Ray-Gueniot, S., Mazuy, C., Gaspard, C.E.,<br />

Jaubert, G., Perrin, G., Vernozy-Rozand, C. (1999): Risk linked to an<br />

enterotoxigenic strain <strong>of</strong> Staphylococcus lentus during the manufacture and<br />

ripening <strong>of</strong> <strong>raw</strong> <strong>goat</strong>s’ <strong>milk</strong> Camembert-type cheeses. Rev. Med. Vet. 150 (8–<br />

9), 703–708.<br />

Morgan, F., Massouras, T., Barbosa, M., Roseiro, L., Ravasco, F., Kandarakis, I.,<br />

Bonnin, V., Fistakoris, M., Anifantakis, E., Jaubert, G., Raynal-Ljutovac, D.<br />

(2003): Characteristics <strong>of</strong> <strong>goat</strong> <strong>milk</strong> collected <strong>from</strong> small and medium<br />

enterprises in Greece, Portugal and France. Small Rumin. Res. 47, 39–49.<br />

Moroni, P., Pisoni, G., Antonini, M., Ruffo, G., Carli, S., Varisco, G., Boettcher, P. J.<br />

(2005a): Subclinical mastitis and antimicrobial susceptibility <strong>of</strong><br />

Staphylococcus caprae and Staphylococcus epidermidis isolated <strong>from</strong> two<br />

Italian <strong>goat</strong> herds. J. Dairy Sci. 88, 1694-1704.<br />

Moroni, P., Pisoni, G., Ruffo, G., Boettcher, P.J. (2005b): Risk factors for<br />

intramammary infections and relationship with somatic-cell counts in Italian<br />

<strong>dairy</strong> <strong>goat</strong>s. Prev. Vet. Med. 69, 163–173.<br />

Muehlherr, J.E., Zweifel, C., Corti, S., Blanco, J.E., Stephan, R. (2003):<br />

Microbiological quality <strong>of</strong> <strong>raw</strong> <strong>goat</strong>’s and ewe’s bulk-tank <strong>milk</strong> in<br />

Switzerland. J. Dairy Sci. 86, 3849–3856.<br />

Ndegwa, E.N., Mulei, C.M., Mynyua, S.J. (2000): The prevalence <strong>of</strong> subclinical<br />

mastitis in <strong>dairy</strong> <strong>goat</strong>s in Kenya. J. S. Afr. Vet. Assoc. 71 (1), 25-27.<br />

Ndegwa, E.N., Mulei, C.M., Mynyua, S.J. (2001): Prevalence <strong>of</strong> microorganism<br />

associated with udder infections in <strong>dairy</strong> <strong>goat</strong>s on small-scale farms in Kenya.<br />

J. S. Afr. Vet. Assoc. 72 (2), 97-98.


80<br />

Oliver, S.P., Jayarao, B.M., Almeida, R.A. (2005): Foodborne pathogens, mastitis,<br />

<strong>milk</strong> quality and <strong>dairy</strong> food safety. Papers presented at a National Mastitis<br />

Council Annual Meeting. USA.<br />

Peris, S., Caja, G., Such, X. (1999): Relationships between udder and <strong>milk</strong>ing traits<br />

in Murciano-Granadina <strong>dairy</strong> <strong>goat</strong>s. Small Rumin. Res. 33, 171-179.<br />

Perrin, G.G., Mallereau, M.P., Lenfant, D., Baudry, C. (1997): Relationships between<br />

California mastitis test (CMT) and somatic cell counts in <strong>dairy</strong> <strong>goat</strong>s. Small<br />

Rumin. Res. 26, 167-170.<br />

Petrie, A., Watson, P. (1999): Statistics for Veterinary and Animal Science.<br />

Blackwell Science Ltd. London.<br />

Petrifilm. (2001): Coliform count plates interpretation guide. Microbiology<br />

Products. 3M Health Care Ltd. USA.<br />

Ruegg, P.L. (2002): Managing the dry period for <strong>milk</strong> quality. University <strong>of</strong><br />

Wisconsin, Madison. USA.<br />

Ruegg, P.L. (2003): Practical food safety interventions for <strong>dairy</strong> production. J. Dairy<br />

Sci. 86 (E. Suppl.), E1-E9.<br />

Sanchez, A., Contreras, A., Corrales, J.C. (1999): Parity as a risk factor for caprine<br />

subclinical intramammary infection. Small Rumin. Res. 31, 197-201.<br />

Schaeren W, Maurer J. (2006): Prevalence <strong>of</strong> subclinical udder infections and<br />

individual somatic cell counts in three <strong>dairy</strong> <strong>goat</strong> herds during a full lactation.<br />

[Article in German]. Schweiz Arch Tierheilkd. 148 (12), 641-648.<br />

Sevi, A., Albenzio, M., Marino, R., Santillo, A., Muscio, A. (2004): Effects <strong>of</strong><br />

lambing season and stage <strong>of</strong> lactation on ewe <strong>milk</strong> quality. Small Rumin. Res.<br />

51, 251–259.<br />

Shearer, J.K., Harris Jr., B. (2003): Mastitis in <strong>dairy</strong> <strong>goat</strong>s. IFAS Extension.<br />

University <strong>of</strong> Florida. USA.<br />

Valle, J., Gomez-Lucia, E., Piriz, S., Goyache, J., Orden, J.A., Vadillo, S. (1990):<br />

Enterotoxin production by staphylococci isolated <strong>from</strong> healthy <strong>goat</strong>s. Appl.<br />

Environ. Microbiol. 56, 1323-1326.<br />

Wakwoya, A., Molla, B., Belihu, K., Kleer, J., Hildebrandt, G. (2006): A cross<br />

sectional study on the prevalence, antimicrobial susceptibility patterns and<br />

associated bacterial pathogens <strong>of</strong> <strong>goat</strong> mastitis. Intern. J. Appl. Res. Vet.<br />

Med. 4 (2), 169-176.


81<br />

White, E.C., Hinckley, L.S. (1999): Prevalence <strong>of</strong> mastitis pathogens in <strong>goat</strong> <strong>milk</strong>.<br />

Small Rumin. Res. 33, 117-121.<br />

Winter, P., Baumgartner, W. (1999): Evaluation <strong>of</strong> the California mastitis test<br />

reaction in <strong>goat</strong> <strong>milk</strong> and its interpretation. [Article in German]. Dtsch.<br />

Tierarztl. Wochenschr. 106 (1), 30-4.<br />

Zeng, S.S., Escobar, E.N. (1995): Effect <strong>of</strong> parity and <strong>milk</strong> production on somatic cell<br />

count, standard plate count and composition <strong>of</strong> <strong>goat</strong> <strong>milk</strong>. Small Rumin. Res.<br />

17, 269–274.<br />

Zeng, S.S., Escobar, E.N. (1996): Effect <strong>of</strong> breed and <strong>milk</strong>ing method on somatic cell<br />

count, standard plate count and composition <strong>of</strong> <strong>goat</strong> <strong>milk</strong>. Small Rumin. Res.<br />

19, 169–175.<br />

Zweifel, C., Muehlherr, J.E., Ring, M., Stephan, R. (2005): Influence <strong>of</strong> different<br />

factors in <strong>milk</strong> production on standard plate count <strong>of</strong> <strong>raw</strong> small ruminant’s<br />

bulk-tank <strong>milk</strong> in Switzerland. Small Rumin. Res. 58, 63-70.


APPENDIX<br />

Appendix A:<br />

A. GENERAL INFORMATION<br />

1. Farm owner<br />

QUESTIONNAIRE<br />

(Principal investigator: Epi Taufik)<br />

Name:<br />

2. a. Address<br />

Street<br />

Telephone/MP<br />

Village<br />

Sub district<br />

FARM ID<br />

b. Farm characteristics<br />

Location in the residence<br />

area<br />

No. <strong>of</strong> animals<br />

No. <strong>of</strong> workers<br />

3. Educational level<br />

1. None<br />

2. Elementary school<br />

3. Secondary school<br />

4. University<br />

Male<br />

Age<br />

Female<br />

Age<br />

B. GENERAL FARM CONDITION AND MANAGEMENT PRACTICES<br />

4. Herd size<br />

1 200 heads


83<br />

5. Animal housing<br />

1 Elevated<br />

2 On the ground<br />

6. Type <strong>of</strong> house<br />

1 Pen<br />

2 Loose housing barn<br />

7. Ventilation<br />

1 Good<br />

2 Poor<br />

8. House for lactating <strong>goat</strong>s<br />

1 Yes<br />

2 No<br />

9. House surface material<br />

1 Bamboo<br />

2 Wood<br />

10. Surface condition<br />

1 Good<br />

2 Poor<br />

11. General hygiene status <strong>of</strong> the farm<br />

1 Good<br />

2 Poor<br />

12. Special worker for <strong>milk</strong>ing?<br />

1 Yes<br />

2 No<br />

13. Hygiene status <strong>of</strong> workers?<br />

1 Good<br />

2 Poor


84<br />

14. Source <strong>of</strong> water?<br />

1 Tap<br />

2 Well<br />

15. Water storage?<br />

1 Closed<br />

2 Open<br />

16. Is water chlorinated?<br />

1 Yes<br />

2 No<br />

17. Stocking density?<br />

1 Low<br />

2 Medium<br />

3 High<br />

18. Presence <strong>of</strong> other animal species in the farm?<br />

1 Yes<br />

2 No<br />

C. MILKING PRACTICES<br />

20. How do you <strong>milk</strong> the <strong>goat</strong>?<br />

1 Machine <strong>milk</strong>ing<br />

2 Hand <strong>milk</strong>ing<br />

21. Is there a special place for <strong>milk</strong>ing the animal?<br />

1 Yes<br />

2 No<br />

22. How many times is the <strong>goat</strong> <strong>milk</strong>ed?<br />

1 Once a day<br />

2 Twice a day


85<br />

23. Is pre-<strong>milk</strong>ing washing done?<br />

1 Yes<br />

2 No<br />

24. Is pre-<strong>milk</strong>ing drying done?<br />

1 Yes<br />

2 No<br />

25. Is pre-dipping done?<br />

1 Yes<br />

2 No<br />

26. Is fore-stripping done?<br />

1 Yes<br />

2 No<br />

27. Is post-dipping done?<br />

1 Yes<br />

2 No<br />

D. GOAT CONDITION<br />

28. Breed <strong>of</strong> <strong>goat</strong>?<br />

1<br />

2<br />

3<br />

29. Animal parity?<br />

1 Primiparous<br />

2 Multiparous<br />

If multiparous in<br />

which parity?<br />

30. Animal lactation stage?<br />

1 First<br />

2 Second<br />

3 Third


86<br />

31. Udder halves symmetric?<br />

1 Yes<br />

2 No<br />

32. Teat end condition scoring*<br />

1 No ring<br />

2 Slightly or smooth<br />

rough ring<br />

33. Teat skin condition scoring**<br />

Score<br />

0<br />

1<br />

2<br />

3<br />

4<br />

5<br />

34. Teat shape?***<br />

1 Normal<br />

2 Dilated<br />

3 Generally dilated<br />

35. Udder hygiene scoring****<br />

Score<br />

0<br />

1<br />

2<br />

3<br />

4<br />

36. Udder inflammation? (<strong>from</strong> CMT result)*****<br />

1 Normal<br />

2 Inflammation<br />

37. Appearance <strong>of</strong> <strong>milk</strong>?<br />

1 Normal<br />

2 Abnormal


87<br />

38. If no. 37 is abnormal, please check below!<br />

1 Discoloration<br />

2 Clotting<br />

3 Watery<br />

4 Blood<br />

5 Off odor<br />

Remarks regarding the above-mentioned scoring are as follows:


88<br />

(*) Teat end scoring<br />

Since no rough ring and very rough ring teat ends were found, the scoring was made<br />

only for no ring and smooth or slightly rough ring (Mein et al., 2001)


89<br />

(**) Subjective Teat Skin and Teat End Evaluation System, University <strong>of</strong> Vermont,<br />

USA (cited <strong>from</strong>: Goldberg et al., 1994)<br />

TEAT SKIN CONDITION SCORING<br />

0 = Teat skin has been subjected to physical injury (e.g. stepped on or frostbitten) not<br />

related to the treatment, or the quarter is nonlactating.<br />

1 = Teat skin is smooth and free <strong>from</strong> scales. cracks, or chapping.<br />

2 = Teat skin shows some evidence <strong>of</strong> scaling<br />

3 = Teat skin is chapped. Some small warts may be present.<br />

4 = Teat skin is chapped and cracked, Redness, indicating inflammation, is present.<br />

Numerous warts may be present.<br />

5 = Teat skin is severely damaged and ulcerative with scabs or open lesions. Large or<br />

numerous warts are present that interfere with teat end function<br />

- Since no score <strong>of</strong> 0, 3, 4 and 5 were found, the scoring was only for 1 and 2<br />

(***) Example for teat shape scoring<br />

Normal<br />

Dilated<br />

Generally dilated


90<br />

(****) udder hygiene scoring was adopted <strong>from</strong> scoring for cow’s udder<br />

(Ruegg, 2002)<br />

- No scores <strong>of</strong> 3 and 4 were found, so the scores were only for 1 and 2<br />

(*****) CMT result:<br />

- 0 or Trace = Normal (negative)<br />

- +1, +2, +3 = Inflammation (positive)<br />

(Wakwoya et al., 2006)<br />

Example <strong>of</strong> +3 CMT reaction <strong>of</strong> <strong>milk</strong><br />

sample (gel like form) indicated that the<br />

udder had inflammation


91<br />

Appendix B: Lists <strong>of</strong> materials and equipments<br />

1 . Equipment and materials<br />

- Eppendorf tubes<br />

- Autoclave<br />

- Balance with a 2000 g-weights capacity and a sensitivity <strong>of</strong> 0.1 g<br />

- Bunsen burner<br />

- Culture tubes, 16*150 and 20*150 m<br />

- Incubator<br />

- Ose/loop<br />

- Laboratory refrigerator, - 20 o C and -1 to 4 o C<br />

- Sterile Petri dishes, 15*100 mm<br />

- Sterile Hockey stick<br />

- Petrifilm plates for Coliform isolation (3M Petrifilm, USA)<br />

- Sterile pipettes<br />

- Micropipette<br />

- Micropipette tip<br />

- Sterile culture tubes<br />

- Test or culture tube racks<br />

- Vortex mixer<br />

- Ice box, 24 liters<br />

- Beakers, and containers<br />

- Sterile 500, 1000 and 2000 ml Erlenmeyer flasks, sterile 250 and 500 ml<br />

- Sterile Schott Duran bottles 50, 250 ml<br />

- Marker pen<br />

2 . Media, reagents and chemicals<br />

- Maximum Recovery Diluent (MRD) (Merck, Germany)<br />

- Brain Heart Infusion Broth (BHI) (Merck, Germany)<br />

- Plate Count Agar (PCA) (Merck, Germany)<br />

- Baird Parker Agar (BPA) (Merck, Germany)


92<br />

- Sterile aquadestila (Faculty <strong>of</strong> Veterinary Medicine, Bogor Agricultural University)<br />

- Egg yolk tellurite (Faculty <strong>of</strong> Veterinary Medicine, Bogor Agricultural University)<br />

- Rabbit plasma (Faculty <strong>of</strong> Veterinary Medicine, Bogor Agricultural University)<br />

- CMT reagents (Faculty <strong>of</strong> Veterinary Medicine, Chiang Mai University)<br />

- Alcohol/Ethanol 95% (PT Kimia Farma, Indonesia)<br />

Appendix C: Calculation <strong>of</strong> total aerobic mesophilic bacteria/total plate count and<br />

Staphylococcus spp. (coagulase positive and negative)<br />

1. Calculation <strong>of</strong> total aerobic mesophilic bacteria/total plate count<br />

1.1 General case (for the dishes containing 15 – 300 colonies)<br />

N =<br />

∑ C<br />

[(n1) + (n2 + 0.1)] x (d)<br />

N<br />

∑ C<br />

n1<br />

n2<br />

d<br />

= Number <strong>of</strong> colonies per ml <strong>of</strong> product<br />

= Sum <strong>of</strong> all colonies on all plates counted<br />

= Number <strong>of</strong> plates selected at the first dilution<br />

= Number <strong>of</strong> plates selected at the second dilution<br />

= Dilution rate corresponding to the first dilution selected<br />

1.2. Estimation <strong>of</strong> low numbers<br />

1.2.1 If the two dishes contained less than 15 colonies, the formula was simplified<br />

and only the arithmetical mean was used for calculation<br />

N = y/d<br />

y<br />

d<br />

= Arithmetical mean <strong>of</strong> the colonies counted on two dishes<br />

= The dilution factor <strong>of</strong> the initial suspension


93<br />

1.2.2 If the two dishes did not contain any colonies, the results are to be expressed as<br />

follows:<br />

- Less than 1/d per ml, where d is the dilution factor <strong>of</strong> the initial suspension<br />

2. Calculation <strong>of</strong> Staphylococcus spp. (coagulase positive and negative)<br />

2.1 Calculation <strong>of</strong> the number a <strong>of</strong> either coagulase positive or negative staphylococci<br />

identified for each plate selected<br />

a = (b c /A c x c c ) + (b nc /A nc x c nc )<br />

A c<br />

A nc<br />

b c<br />

b nc<br />

c c<br />

c nc<br />

= Number <strong>of</strong> typical colonies submitted to the coagulase test<br />

= Number <strong>of</strong> atypical colonies submitted to the coagulase test<br />

= Number <strong>of</strong> typical colonies which have been shown to be coagulase<br />

positive/negative<br />

= Number <strong>of</strong> atypical colonies which have been shown to be coagulase<br />

positive/negative<br />

= Total number <strong>of</strong> typical colonies seen on the plate<br />

= Total number <strong>of</strong> atypical colonies seen on the plate<br />

2.2 Calculation <strong>of</strong> the number N <strong>of</strong> identified coagulase positive or negative staphylococci<br />

in the test portion<br />

N =<br />

∑ a<br />

V x [(n1) + (n2 + 0.1)] x (d)<br />

N<br />

∑ a<br />

= Number <strong>of</strong> colonies per ml <strong>of</strong> product<br />

= Sum <strong>of</strong> the coagulase positive or negative staphylococcal colonies<br />

identified on all the dishes selected


94<br />

V = Volume <strong>of</strong> inoculum on each dish, in mililitres (in this study 0.1 ml =<br />

spreading method)<br />

n1 = Number <strong>of</strong> plates selected at the first dilution<br />

n2 = Number <strong>of</strong> plates selected at the second dilution<br />

d = Dilution rate corresponding to the first dilution selected<br />

2.3 Estimation <strong>of</strong> low numbers<br />

2.3.1 If the two dishes, corresponding to the test sample or the initial suspension each<br />

contain less than 15 identified colonies, the calculation is as follows:<br />

N =<br />

∑ a<br />

V x 2 x d<br />

∑ a = Sum <strong>of</strong> the coagulase positive or negative staphylococcal colonies<br />

identified on all the dishes selected<br />

V = Volume <strong>of</strong> inoculum on each dish, in mililitres (in this study 0.1 ml =<br />

spreading method)<br />

d = Dilution rate corresponding to the first dilution selected<br />

2.3.2 If the two dishes, corresponding to the test sample or the initial suspension do<br />

not contain any colonies, the results are to be expressed as follows:<br />

- Less than 10/d per ml, where d is the dilution factor <strong>of</strong> the initial suspension


96<br />

CURRICULUM VITAE<br />

Name : Epi Taufik<br />

Place/date <strong>of</strong> birth : Ciamis, Indonesia December 2 1975<br />

Sex : Male<br />

Religion : Islam<br />

Marital Status/children : Married/one daughter<br />

Present status : Lecturer/academic staff <strong>of</strong> lab. <strong>of</strong> animal product<br />

technology, Faculty <strong>of</strong> Animal Science, Bogor<br />

Agricultural University (IPB) Indonesia.<br />

http://www.ipb.ac.id<br />

Home Address : Perumahan IPB Alamsinarsari Jl. Dahlia D64<br />

Darmaga, Bogor, Indonesia Post code 16680<br />

email: etaufik@yahoo.com<br />

Office Address : Laboratory <strong>of</strong> Animal Product Technology,<br />

Department <strong>of</strong> Animal Science and Technology,<br />

Faculty <strong>of</strong> Animal Science, Bogor Agricultural<br />

University. Jl. Agatis Kampus IPB Darmaga,<br />

Bogor, West Java, INDONESIA 16680. Phone and<br />

Fax. 62-251-629104<br />

email: fapetipb@indo.net.id<br />

EDUCATION:<br />

Level <strong>of</strong><br />

Education<br />

University<br />

(undergraduate)<br />

School Name<br />

Study Program Animal<br />

Product Technology,<br />

Department <strong>of</strong> Animal<br />

Production, Faculty <strong>of</strong><br />

Animal Science, Bogor<br />

Agricultural University,<br />

Indonesia<br />

Year<br />

Diploma and date<br />

<strong>of</strong> issued<br />

1994 - 1999 Diploma No.<br />

1006990025<br />

Graduate Status:<br />

With Honor<br />

February 27 1999


97<br />

Master degree<br />

Study Program <strong>of</strong><br />

Veterinary Public Health,<br />

Graduate School <strong>of</strong> Bogor<br />

Agricultural University,<br />

Indonesia<br />

2004 - present - (postponed, will be<br />

continued January<br />

2008 for final thesis<br />

research)<br />

TRAININGS: (Last 5 years)<br />

No. Training Organizer Year<br />

1. Research Proposal Making IPB in cooperation with<br />

Directorate General <strong>of</strong> Higher<br />

Education<br />

2. Community Empowerment<br />

Program<br />

3. National Training on<br />

Microbiology in Animal<br />

Science and Veterinary Public<br />

Health<br />

INDONESIA<br />

IPB in cooperation with<br />

Directorate General <strong>of</strong> Higher<br />

Education<br />

INDONESIA<br />

Ministry <strong>of</strong> National<br />

Education in cooperation<br />

with Department <strong>of</strong><br />

Veterinary Public Health,<br />

Faculty <strong>of</strong> Veterinary<br />

Medicine IPB<br />

INDONESIA<br />

2004<br />

2004<br />

2004


98<br />

PROFESSIONAL ORGANIZATIONS:<br />

1. INDONESIAN SOCIETY FOR MICROBIOLOGY/PERHIMPUNAN<br />

MIKROBIOLOGI INDONESIA / PERMI Member Registration No. 002 – BGR<br />

298<br />

RESEARCH EXPERIENCES:<br />

1. Physical, chemical and <strong>microbiological</strong> characteristics <strong>of</strong> dadih (Indonesian<br />

traditional fermented <strong>milk</strong> food) made <strong>from</strong> cow’s <strong>milk</strong> fermented with different<br />

starter probiotic bacteria combinations stored at different temperatures. 2003<br />

2. Antimicrobial activity <strong>of</strong> dadih (Indonesian traditional fermented <strong>milk</strong> food) made<br />

<strong>from</strong> cow’s <strong>milk</strong> fermented with different starter probiotic bacteria combinations.<br />

2004<br />

3. Antimicrobial activity <strong>of</strong> different fermented <strong>goat</strong> <strong>milk</strong> products <strong>from</strong> different<br />

breeds <strong>of</strong> <strong>goat</strong>s. 2005<br />

4. Microbiological Investigation <strong>of</strong> Raw Goat Milk <strong>from</strong> Commercial Dairy Goat<br />

Farms, in Bogor Indonesia. 2006-2007.<br />

5. Survival <strong>of</strong> Pathogenic Bacteria in Yoghurt and Kefir during Fermentation and<br />

Cold Storage. 2007<br />

RESEARCH GRANTS:<br />

1. Young Academic Staff Research Grant <strong>from</strong> Bogor Agricultural University<br />

(IPB), 2003<br />

2. Young Academic Staff Research Grant Bogor Agricultural University (IPB),<br />

2004<br />

3. Research Grant under A2 Competition Grant Program, Directorate General <strong>of</strong><br />

Higher Education, Ministry <strong>of</strong> National Education, Indonesia, 2005<br />

4. Research Grant under A2 Competition Grant Program, Directorate General <strong>of</strong><br />

Higher Education, Ministry <strong>of</strong> National Education, Indonesia, 2007<br />

PROFESSIONAL EXPERIENCES:<br />

1. Internship at PT Sierad Produce, Poultry Processing Plant, 1998


99<br />

2. Assistant specialist in the agricultural sector for project benefit evaluation <strong>of</strong><br />

projects funded by the JAPAN BANK FOR INTERNATIONAL<br />

COOPERATION (JBIC) Loan INP 22 dan 23, 2002-2003<br />

SCIENTIFIC PUBLICATIONS:<br />

1. Production Technology and Product Quality Control at PT Sierad Produce Tbk.<br />

Poultry Processing Plant, Parung, Bogor. Internship report 1998<br />

2. Shelf life <strong>of</strong> duck carcasses chlorinated with different concentration levels. Jurnal<br />

Peternakan dan Lingkungan, Vol. 08. No. 2 (Juni 2002) ISSN: 0852-4092<br />

(Indonesia National Scientific Journal)<br />

3. Quality <strong>of</strong> dadih (Indonesian traditional fermented <strong>milk</strong> food) fermented with<br />

probiotic starter bacteria and stored at low temperature: I. chemical characteristic.<br />

Media Peternakan. Vol. 27 No. 3: 88-100, December 2004 (Indonesia National<br />

Scientific Journal)<br />

4. Quality <strong>of</strong> dadih (Indonesian traditional fermented <strong>milk</strong> food) fermented with<br />

probiotic starter bacteria and stored at low temperature: II. physical,<br />

organoleptical and <strong>microbiological</strong> characteristics. Media Peternakan. Volume 28<br />

No. 1 : 13- 20 April 2005 (Indonesia National Scientific Journal)<br />

5. Physical, Chemical and Microbiological Characteristics <strong>of</strong> Dadih (Indonesian<br />

Traditional Fermented Milk Food) Made <strong>from</strong> Cow’s Milk Fermented with<br />

Different Starter Probiotic Bacteria Combination and Stored at Different<br />

Temperatures. Research Report, Research Institute <strong>of</strong> IPB, 2003<br />

6. Antimicrobial Activity <strong>of</strong> Dadih Fermented with Probiotic Starter Bacteria.<br />

Research Report, Research Institute <strong>of</strong> IPB, 2004<br />

SCHOLARSHIP AWARDS<br />

1. McDonald Indonesia Family Restaurant Co. Ltd. for Undergraduate Study, 1994 –<br />

1999<br />

2. Scholarship for Postgraduate Study, Ministry <strong>of</strong> National Education <strong>of</strong><br />

The Republic <strong>of</strong> Indonesia, 2004 – 2006 (for Master study at Bogor Agricultural<br />

University)


100<br />

3. Deutscher Akademischer Austauschdienst (DAAD)/German Academic Exchange<br />

Service for Postgraduate Study in Master <strong>of</strong> Veterinary Public Health in the Joint<br />

Master Program between the Freie Universitaet Berlin, Germany and Chiang Mai<br />

University, Thailand, 2005 - 2007

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!