Inter‐relationship between egg weight, parental age and embryonic development

Abstract

A clear positive correlation was evident between egg weight at setting and embryo weight at 18 days of incubation for broiler eggs laid at or after 32 wk of age. The weight of embryos from the same size eggs depended upon a curvilinear function of the age of parent flock, with the largest increase in embryo weight occurring between 28-32 wk of age. Hatching weight was highly correlated with egg size at setting. Flock age had no effect on hatching weight from a particular sized egg. Within any of the 5 ages studied, chicks from smaller eggs tended to hatch slightly (but not significantly) earlier than those from larger eggs.