Eggs and Chicks from Broiler Breeders of Extremely Different Age

Abstract Eggs and broiler chicks originating from breeder flocks having extremes in age (27 vs. 62 wk old) wee examined. Eggs from the older flock were heavier and had a greater proportion of yolk and smaller proportions o albumen and shell than those from 27 wk old birds. Yolks of eggs from young breeders and albumen of eggs from old breeders had greater percentage of moisture. Chick and yolk sac weights from old breeders were greater, but yolk sac proportions were not different. Analyses for crude protein and amino acids, as well as ash and minerals of eggs, chicks, and yolk sacs, did not reveal obvious differences in concentrations. Phosphorus in the yolk sac of chicks from young breeders appeared to be low, indicating that additional supplementation in the first feed may be appropriate.