Estimation of genetic parameters of juvenile traits in synthetic coloured broiler male line (PB-1) using REML animal model

The synthetic-coloured broiler male line (PB-1) population was evaluated for variance and co variance components of juvenile traits viz. body weight at day old, 2^nd, 4^th, 5^th and 6^th weeks of age; keel length and shank length at 5^th week of age using REML animal model. The 5^th week body weight and conformation traits shown significant difference (P<0.01) for both hatch and sex effects. The total heritability estimates (h²_t) for body weight at day-old, 2^nd, 4^th and 5^th body weight was 0.44, 0.19, 0.32 and 0.17; keel length and shank length 0.15 and 0.22, respectively. The direct additive genetic correlation between the body weights was positive, high in magnitude and highly significant (P<0.01) between them except for the day-old body weight. The phenotypic correlation of conformation traits with body weights were positive and moderate to high in magnitude except for the day-old body weight which was low. The precise estimation of genetic parameters, heritability and correlation with REML model improve accuracy of the estimates, thus enabling the breeder’s decision related to the selection and breeding strategy being more accurate and ultimately aiding in genetic improvement of the populations.