Genetic and phenotypic parameters for litter traits of D'Man ewes

Abstract

ABSTRACTA total of 1754 records for litter traits of 458 D'man ewes sired by more than 45 rams were analysed to estimate repeatability, heritability and genetic and phenotypic correlations. Repeatability estimated by the intraclass correlation method was 0·11, 0·11, 0·12 and 0·15 for litter sizes at birth and at weaning and litter weights at birth and at weaning, respectively. Paternal half-sib estimates of heritability were 0·09 (s.e. 0·06), 0·04 (s.e. 0·05), 0·15 (s.e. 0·07) and 0·08 (s.e. 0·05), respectively. Genetic correlations among the traits were all positive and varied from 0·17 to 0·72, whereas phenotypic correlations ranged from 0·68 to 0·86.