Desired Gain Selection Indices for Pre-Weaning Body Weights in Zaraibi Male Kids in Egypt

The aim of the current study was to estimate the genetic parameters and evaluate various desired-gain selection indices for pre-weaning live body weights of Zaraibi male kids in Egypt. From 2005 to 2012, data of 763 does mated with 75 bucks of Zaraibi goats raised at El-Serw Experimental Station belonging to the Animal Production Research Institute were collected. Data were analyzed with REML using animal model to determine genetic parameters and using SAS to construct different desired-gain selection indices. Direct heritability (h²_d) for BW, W30, W60 and WW were 0.25, 0.22, 0.31 and 0.35, respectively. Corresponding maternal heritability (h²_m) for aforementioned traits were 0.145, 0.141, 0.099 and 0.073, respectively. While total heritability (h²_t) above traits were 0.25, 0.38, 0.48, 0.49 and 0.34, respectively. The direct-maternal genetic correlations (r_dm) were positive for W30 (0.35) and W60 (0.47), while negative for BW (-0.23) and WW (-0.19). Genetic correlations (r_d1d2) among studies traits ranged from 0.80 to 0.95, while phenotypic correlations (r_p1p2) among all traits ranged from 0.69 to 0.84. Comprisable between selection indices was the highest number of generations required (T) to attain the pre-estimated goals was 5.6143 in I₄. In contrast, the lowest number of generations required (T) was 2.0220 in I₁₄. Therefore, I₁₄ was considered the best selection index lead to save time and efforts for genetic improvement of studied traits in Zaraibi male kids in Egypt.