Genetic analysis of growth traits in Salem Black goats under farm conditions.

Abstract

In this study, data on pedigree, production traits for 19 years (2002-2022) of Salem Black goat from the Mecheri Sheep Research Station, Tamil Nadu, India was used. Various growth traits viz., birth weight (BW), weaning weight (WW), 6-month weight (6W), 9-month weight (9W), 12-month weight (YW), pre- and post-weaning average daily gain (ADG) (3-6, 6-9, 9-12 and 3-12 months) were analyzed. Univariate analysis was carried out after correcting for significant non-genetic factors. (Co)variance components for different production and functional traits were estimated by Restriction Maximum Likelihood method (REML) using WOMBAT. Heritability estimates for most of the growth traits were medium providing better scope for selection. Direct heritability estimates for BW, WW, 6W, 9W and YW, pre- and post-weaning ADG (3-12) were 0.177 ± 0.066, 0.094 ± 0.055, 0.111 ± 0.068, 0.123 ± 0.082, 0.181 ± 0.122, 0.118 ± 0.060 and 0.188 ± 0.126 respectively. Through bivariate analysis genetic and phenotypic correlations between growth traits were obtained. Positive, medium to high genetic correlation was observed in post-weaning body weight traits which would support multistage selection. Similar positive and medium to high genetic correlation between pre- and post-weaning ADG (3-6 and 3-12 months) with post- weaning body weight traits would facilitate indirect selection. Breeding values (EBV) for BW, WW, 6W, 9W, YW, pre- and post-weaning ADG (3-12 months) were estimated. High genetic variability was observed in weaning and post- weaning body weight traits. The findings of this study could further aid in the improvement of the breeding programme.