Genetic improvement of body weight has received great attention in the poultry industry. So, this study was carried out on the flock of Dandarawi chicken through five successive generations at the Poultry Research Farm, Faculty of Agriculture, Assiut University to determine the genetic response in growth measures due to selection for high body weight at 8 weeks of age and estimate the realized heritabilities.
The chicks in each generation divided into two lines, selected line for high body weight at 8 weeks of age and control line. Body weight, shank length and keel length were recorded, selection differential, cumulative selection response and realized heritability for growth traits over generations were estimated.
The results showed that the birds of selected line were higher in body weight, shank and keel length compared with those in control line (P≤0.01) at different ages. There were significant differences (P≤0.01) between generations, lines, and sexes in all traits studied at different ages. Also, there were significant interactions between the main effects considering the different studied traits.
After five generations, the cumulative responses to selection for body weight were 4.75, 110.79, 223.80, 321.41, 297.89, and 323.53 gram at 0, 4, 8, 12, 16, and 20 weeks of age, respectively. Also, realized heritability estimates varied from moderate to high (0.30- 0.61) for all growth traits studied over generations at different ages.
According to the obtained results, it is necessary to continue the program of selection to achieve further improvement in growth measurements in Dandarawi chicken.