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

More documents

Recommendations

Info

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

11 ASSTRACT Phenotypic and genetic parameters of some reproductive traits in swine were estimated from 1 ,264 Lrtters of first parÍty }lanagra gilts farrowed between L967 anô, 1977. Means and standard deviations for the traits of total number of pigs born, number born alive, number at weaning, average birth weÍght and average weaning weight were: 9.681 2.22, 9.L7!2.L3, 7.68!2.L6, 1.3410.18 kg and 10.66!I.52 kg, respectively. SignÍficant dÍfferences were observed among three different farrorn'ing groups and among years in all reproductive traits. HeritabilíÈy estimates r,rere as follows: total number of pigs born, 0.0710.12; number of pigs born alive, 0.0210.12; number of pigs weaned, 0.0110.12; average birth weight, 0.36t0.11; and average weaning weight, 0.3710.11. PhenotypÍc correlations among the three different litter size traits were highly positive and the correlation between average birth weíght and average weaning weight was moderately posÍtive. Phenotypic correlations between litter si-ze' traits and average pig r.igfrt traits were moderately negative except for the correlaËion of nr:mber weaned r¿ith average bírth weight. Genetic correlations between total number born and average pig weight at birth and at weaning were 0"3010.46 and 0.92! 0.09, respectively. Genetic correlations betv¡een average weaning weight and nr:mber of pigs weaned and average birth weight r,¡ere 0.5211.05 and 0 .77x0.20, respectively. Phenotypic and genetÍc parameters for carcass aeasurements and age to market weight were estimated from data on 1r455 Managra pigs consisting of 425 barrows and 1,030 gilts over a seven year period (1971- 1977). Means and standard devÍations for 10 traits \^rere as follows:
iÍi carcass length,77.22!2.47 cm¡' maximum shoulder fat thíckness, 4.1710.50 cmi mininsrn mid-back fat thickriess, 2.01t0.37 cur; loin fat thickness, 3.2L!0.42 cm; total fat thickness, 9.40tL.04 cm;1oin eye area,30.171 2 3.70 cm-; grade index, 101.84t2.80; 7" lnam weight, 26.6911.62; lnam surface area, L25.25!L5.34 "*2; and age Lo market weight, 188.40115.06 days. T'he differences between barrorvs and gilts.\^rere significant for all c.arcass trait.s and age to market rveight. Heritabilities estimated from sire and. dam components Treïe: carcass length, 0.62!0.08; maxímum shoulder fat, 0.39t0.07; rninimr:m mid-back fat, 0.3310.07; loin fat, 0.24!0.07; total fat thickness,0.4510.07; loin eye area,0.5310.07; grade index, 0.4910.07; % ham weight, 0.24!0.07; harn surface aÍea, 0.41t 0.07; % predícted yíe1d, 0.56t0.08; and age to narket weight, 0.59t0.08. Phenotypic and genetÍc correlation coefficÍents r¡ere calculated from analysis of covariance. Several genetic correlation coefficients r¿ere outside the theoretical range and the standard errors for most of the genetic correlatÍon coefficients were hÌgh. Phenotypic and genetic correlatíons among eleven traits were in the same direction buÈ genetic correlations tended to be higher.
Page 1 and 2: ESTIMATION OF GENET]C AND PHENOTYPI
Page 3: ACKNOI^rLEDGÐ{ENTS The author wish
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 and 24: 13 and backfat thickness r^7as nega
Page 25 and 26: Table 3. Managra breed development
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:
^Appendix 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?