Estimation of genetic parameters of body weights and carcass traits in English White quail

In order to estimate genetic parameters of body weights in difference ages and carcass traits in English White quail using first filial generation of 105 pair of sires and dams which was randomly selected from base population and were mated in cages. Body weight at one day- old, 7, 14, 21, 28 and 35 days and carcass traits including breast, thigh and carcass weights for the progenies were recorded. Average body weights for day-old and 5 week of age were 9.06 and 192.88 g, respectively. (Co) Variance components for the above traits were estimated using univariate and bivariate animal model and restricted maximum likelihood procedure. Mostly of traits studied of phase statistical significant and females weights were more than males and this difference was varied from 0.11 until 12.28 g for one day-old and 5 week body weights, respectively. Heritability of day-old, 7, 14, 21, 28 and 35 days body weights were estimated as 0.73±0.04, 0.32±0.06, 0.30±0.06, 0.22±0.05, 0.22±0.05 and 0.25±0.06, respectively and for breast, thigh and carcass weights and, breast, thigh and carcass percent were as 0.26±0.06, 0.28±0.06, 0.28±0.05, 0.127±0.04, 0.19±0.06 and 0.048±0.03, respectively. Body weights of 28 and 35 days had highest genetic and phenotypic correlations with breast, thigh and carcass weights. Considering moderate heritability of body weight at fourth week of age and high genetic correlations of this trait with other body and carcass components weights and also possibility of sex determination at this age, selection of quails at this age may be preferred.