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et al., 2001b), these results being in agreement with the dairy cattle literature (Rupp and Boichard, 2003). Moreover, the genetic correlations between LSCS and several udder-type traits such as teat placement or udder depth were moderately favourable as already shown in cattle and ranged from -0.10 to -0.32 (Legarra and Ugarte, 2005, Barillet et al., 2006). There is evidence that selection on milk traits only would lead in the long term to “baggy” udders more difficult to milk by machine and more susceptible to mastitis. Therefore it is relevant to include in the breeding objective functional traits related to udder morphology (udder scores) and udder health (SCS) for dairy sheep breeds profiting for several decades from efficient selection on milk traits only. Since 2005, the Lacaune breed has been selected on a total merit index giving the same relative weights to milk production and udder morphology and health (Barillet et al., 2006). It is expected that SCC of the ewes will decrease by 54 % in 10 years, corresponding roughly to a genetic decrease of about a third of the bulk milk SCC. Currently the selection for mastitis resistance is based on a linear decrease of milk SCC. To validate this strategy, in the INRA Lacaune flock, an experiment based on SCC divergent lines has been in progress since 2003 (Rupp et al., 2006) to study the consequences of such a SCC selection on different components of the host’s resistance to IMI . The preliminary results are promising: in 2005, the production during the first lactation of the two SCC lines was similar: closed to 0.9 liters per milking, while the SCS difference was 1.6, i.e. 400,000 cells/ml for the low SCC line versus 850,000 cells/ml for the high SCC line. Moreover, low SCC line ewes showed no clinical cases of mastitis, lower infection rate and better ability to recover from infections during lactation. 4.4. Conclusion At the flock level, the control of SCC has to be based on several complementary approaches: - lessening of the infection pressure: decrease of the new infections by culling the most infected ewes (if possible) or carrying out a “selective” drying-off treatment. An “exhaustive individual SCC picture” by sampling all the milked ewes would be recommended to select the sheep to be culled or treated. The Figure 11 illustrates the evolution of bulk tank SCC between 2001 and 2002 for flocks involved in a control program in 2001. There were 2 levels of “control”: normal or simplified differing from the realization or not of an exhaustive SCC (all the other actions being comparable). It can easily be noticed the decrease of SCC after the iSCC results: the sheep with high SCC had been dried off (or culled) during the year 2001. For the year 2002, a better SCC bulk level was noticed for the flocks involved on the normal action, the decrease of SCC being about 100,000 cells/ml or minus 20 %. - the limitation of new infections using all the preventive possible actions, at a reasonable cost, in accordance with the management of the flock. - the genetic control for the breeds profiting for several decades from an efficient selection on milk traits only. 52
Figure 11. Evolution of the average bulk SCC of the 3 types of flocks according to the level of control : simplified, normal, control = not involved in the program) (Lagriffoul G., 2003) SCC (mensual geometric means *1 000 cells/ml) 900.0 800.0 700.0 600.0 500.0 400.0 300.0 5 – Final Conclusions 2001_2 2001_2 2001_2 2001_3 2001_3 2001_3 2001_4 2001_4 2001_4 2001_5 2001_5 2001_5 2001_6 2001_6 2001_6 2001_7 2001_7 2001_7 2001_8 2001_8 2001_8 The results obtained during the past years have increased the knowledge on somatic cell counts in dairy sheep in several areas: - the improvement of rapid animal-side tests - the assessment of bacteriological cure and new infection rates - the estimation of true efficiency of preventative actions - the relationships with milk flow kinetics - the development of vaccines The lack of statistics for dairy sheep does not allow relevant comparisons of the SCC situation in different countries. At a large scale (country or area of production), the average value of bulk SCC ranges from 400,000/500,000 to 1,000,000/1,200,000 cells/ml, and sometimes more. But the control of SCC is now being effective in several countries and “low” levels of average SCC are being described. For example, in 2005, the average SCC in Roquefort area (2,500 flocks – 180 millions liters) was about 500,000 cells/ml, corresponding to a 33 % decrease during the last 10 years based on preventative and curative actions; not yet including genetic control which just started in 2005. 53 2002-1 2002-1 2002-1 2002-2 2002-2 2002-2 2002-3 2002-3 2002-3 2002-4 2002-4 2002-4 2002-5 2002-5 2002-5 2002-6 2002-6 2002-6 2002-7 2002-7 2002-7 2002-8 2002-8 2002-8 simplified normal control
Page 1 and 2:
Proceedings of the 12 th Annual GRE
Page 3 and 4:
Symposium Organizing Committee Yves
Page 5 and 6:
Table of Contents (cont.) SHEPHERD
Page 7 and 8:
Program of Events (cont.) Friday, N
Page 9 and 10:
Gold: Sponsors Babcock Institute fo
Page 11 and 12: SHEEP DAIRY FARM ECONOMIC ANALYSIS
Page 13 and 14: 3) Recordkeeping a) Degrees of deta
Page 15 and 16: Out of this allocation, the Dairy B
Page 17 and 18: The original plan for Uplands was t
Page 19 and 20: Cheese As previously mentioned, Ple
Page 21 and 22: ORGANIC SHEEP DAIRY: MARKETS AND PR
Page 23 and 24: products that, especially combined
Page 25 and 26: Organic Milk Production Requirement
Page 27 and 28: To become certified, you must first
Page 29 and 30: ATTRA- the National Sustainable Agr
Page 31 and 32: 1.2. The average western Pyrenees d
Page 33 and 34: During the last 15 years, the avera
Page 35 and 36: The growth of the market of Pyrenee
Page 37 and 38: them tested for OPP using the cElis
Page 39 and 40: separate facilities and tested at 4
Page 41 and 42: • Neoplastic tumors Treatment •
Page 43 and 44: STRATEGIC CONTROL OF GASTRO-INTESTI
Page 45 and 46: C. Intestinal cestode parasites (ta
Page 47 and 48: Strategic Timing of Treatment Phase
Page 49 and 50: 1.2. IMI is the main factor influen
Page 51 and 52: 1.3. Use of SCC in order to detect
Page 53 and 54: within-day fluctuation (SCC level a
Page 55 and 56: expensive. But it is necessary to b
Page 57 and 58: The influence of high SCC on cheese
Page 59 and 60: Figure 9. Contribution to bulk tank
Page 61: Regarding the dynamics of the infec
Page 65 and 66: Lafi S.Q. 2005. Use of somatic cell
Page 67 and 68: (Penning et al., 1988). Another stu
Page 69 and 70: Pre-grazing herbage mass (kg DM/ha)
Page 71 and 72: Table 2: Average test day milk prod
Page 73 and 74: Figure 4: Average test day milk fat
Page 75 and 76: lactation ewes (1.66 vs. 1.50 kg/d,
Page 77 and 78: Figure 6: Average change in body we
Page 79 and 80: esults, so an average pasture CP va
Page 81 and 82: Pulina, G. 2002. Dairy Sheep Feedin
Page 83 and 84: light treatments, when all ewes wer
Page 85 and 86: percentage protein (AgSource Milk L
Page 87 and 88: the difference was significant on o
Page 89 and 90: kg), fat (+ 3.0 kg), protein (+ 0.9
Page 91 and 92: Auchtung, T. L., A. G. Rius, P. E.
Page 93 and 94: site of a small settlement for seve
Page 95 and 96: Gonyou, HW and Stookey, JM. 1983. U
Page 97 and 98: SHEPHERD’S DAIRY Kim Curtis Ansel
Page 99 and 100: Breeds As I stated above, we starte
Page 101 and 102: Summary ARTISAN SHEEP MILK CHEESE J
Page 103 and 104: ACCURACY OF THE PORTASCC® MILK TES
Page 105 and 106: Correlation between laboratory resu
Page 107 and 108: CLOVER DALE SHEEP DAIRY John Henry
Page 109 and 110: CARR VALLEY CHEESE - WISCONSIN’S
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Page 113 and 114:
We We We Welcome Welcome You You Yo
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Hudson Valley Camemberts Pure Sheep
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N681 Rollwood Road Antigo, WI 54409
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