Estimation of genetic and phenotypic parameters in a closed ...

More documents

Recommendations

Info

$il\VOLVEMENT OF RETII\OIC ACID II{ - MSpace at the University of ...$

L4 MATERIALS AND ìGTHODS A. Sources of Data I. Reproductive traits The data for 1ítter sLze were obtaíned from the records of the uníversity of Manitoba swine breeding project over the períod of years 1967 to L977 at the Glenlea Research Station. First parity gilts of the Managra breed rîere included in this study. Managra r¡ere developed from a gene pool consisting of about 457á Swedish Landrace , 2O7. IÎessex Saddleback, 15% I,Ielsh ar'ð 707. Minnesota //l-Berkshire-Yorkshire-Tarff^rorth. Table 3 illustrates the pattern of development of the Managra and the current farrowing groups (Parker, f977). Parents of each generation consisted of 20 to 30 boars and 90 to 120 gilts. Selection of parents based on backfat thickness as measured by adjusted live ultrasonic probe, adjr,rsted age to 90 kg live weight and physical soundness. There \¡ras no line crossing among the groups and inbreedíng was rulnimized each generation. LitËers from which fewer than 3 pigs \47ere weaned were not included in the study. The number of liËters which contributed to this study from the diffeïent groups in the different years are lísted ín Table 4. Total number of pigs born, total number of pigs born alive, total number of pÍgs weaned, average bÍrth weight and average weaning weight were the five reproductive traits examined. Average birth weight and average weaning r^reight were adjusted for number born alive and number weaned, respectlvely. The adjustments were used only rvhen calculating phenotypic means. The equation for adjustmenË (Huntsberger, L977) was:
Table 3. Managra breed development patt.ern and the current farrowing groups Line 1 Swedish Landrac 2aro.rp B f arrows each year in Jan.-Febu I{essex I'Ie1sh 45% Sw. Land. Mínn. 20% I{essex Berkshire 157" Welsh Line 3 Yorkshi r 20% M.BuYnTn Tamrn¡ort L957 19s 9 L967 Gene Poollctorrp A farrows each year in May-June. Manaqra Managra group 3crorrp C farrows each year ín Sept..-octo Generation interval ís one year in each group. F (Jr
Page 1 and 2: ESTIMATION OF GENET]C AND PHENOTYPI
Page 3 and 4: ACKNOI^rLEDGÐ{ENTS The author wish
Page 5 and 6: iÍi carcass length,77.22!2.47 cm¡
Page 7 and 8: TABLE OF CONTENTS Page B. Carcass m
Page 9 and 10: va1 LIST OF TABLES Table Page L7 Me
Page 11 and 12: INTRODUCTION The heritabilíty of t
Page 13 and 14: granddaughter on granddam. The heri
Page 15 and 16: Table 1 (Contlnued) Tralcs a n Meth
Page 17 and 18: 7 r^/ith the number of pigs born al
Page 19 and 20: Table 2 (Contlnued) TraÍtg h2 Meth
Page 21 and 22: 11 as 0.31 and 0.40 by Edwardsand O
Page 23: 13 and backfat thickness r^7as nega
Page 27 and 28: L7 Adjusted Y, = Y. - b (Xt-X") whe
Page 29 and 30: 19 9) 'PercenË Ham I{eight The pro
Page 31 and 32: 2I Table 6, Regression coefficients
Page 33 and 34: a') variance is given in Table 7. T
Page 35 and 36: 25 where: "ott(*y) 2 ã: "r(x) = to
Page 37 and 38: ¿/ l. Heritability estimates - The
Page 39 and 40: 29 Standard errors (S.E.) following
Page 41 and 42: 31 tots (*v) toto(*y) = totw(*y) =
Page 43 and 44: -f1 RESULTS AND DTSCUSSION A. Repro
Page 45 and 46: Table i-2. Means and standard devla
Page 47 and 48: a1 Table 13. Estímated heritabilit
Page 49 and 50: Table 14. PhenotypÍca and geneticb
Page 51 and 52: 4L Table 15 - Means and standard de
Page 53 and 54: 43 Table 16. Means and standard dev
Page 55 and 56: 45 Most of the heritabilities deriv
Page 57 and 58: 47 moderately heritable while carca
Page 59 and 60: ,o AJ et 41. (L969), Roy er al. (19
Page 61 and 62: 51 to phenotypic correlations in mo
Page 63 and 64: 53 SI]MMARY AND CONCLUSION Data fro
Page 65 and 66: 55 also improve Ëhe others where s
Page 67 and 68: 57 Flock, D.K. 1970. Genetic parame
Page 69 and 70: APPENDIX s9
Page 71 and 72: Appendix rr. Anal-ysis of covarÍan
Page 73 and 74: Appendlx rrr' Ànalysfs of varlance
Page 75 and 76:
Appendlx IV (Conrinued) Mean cross
Page 77 and 78:
Appendlx IV (Conrlnued) Mean cross
Page 79 and 80:
Appendlx IV (Contlnued) Mean cross
Page 81 and 82:
Âppendix IV (Continued) Mea4 cross
Page 83 and 84:
Appendix IV (Conctnued) Mean crosà
Page 85 and 86:
75 Appendix V. Table of differentia
Page 87 and 88:
77 Appendix VI. (Continued) Body wt
Page 89:
79 Appendix VI. (Continued) Body wt
show all

Estimation of genetic and phenotypic parameters in a closed ...

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

Delete template?

Save as template?