ESTIMATE OF GENETIC AND PHENOTYPIC PARAMETERS FOR LITTER SIZE AND WEANING WEIGHT IN YANKASA SHEEP

Abstract

Data on 964 and 1150 weaning weight and\xa0litter size records respectively, collected over a\xa010-year period on Yankasa Sheep breeding\xa0project at the National Animal Production\xa0Research Institute (N.A.P.R.I.), Zaria, were\xa0used in this study. The analysis was for\xa0estimation of genetic and phenotypic\xa0parameters for litter size and weaning weight\xa0in Yankasa sheep. Estimates of heritability\xa0for litter size and weaning weight were\xa0obtained from paternal half sib intraclass\xa0correlation. The genetic and phenotypic\xa0relationship between the litter size and\xa0weaning weight were estimated from the\xa0covariance and variance components or the\xa0two traits. Least squares means of 1.18±0.02\xa0and 10.67 ±0.11 were obtained for litter size\xa0and weaning weight, respectively. Heritability (h 2 ) estimates or 0.18±0.07 and 0.63±.0.01\xa0were obtained, respectively for litter size and\xa0weaning weight. Genetic and phenotypic\xa0correlations of -0.83±0.052 and 0.23±0.094\xa0respectively, were obtained, between weaning\xa0weight and litter size. Key words : Genetic, Phenotypic, correlations,\xa0litter size, weaning weight heritability