Zelenka and Ceresnakova (2005) found that the total tract starch digestibility coefficient already exceeded 0.96 at 3 d of age for broiler chickens.
The same authors also found that starch digestibility decreased (P < 0.01) linearly with increasing age in fast-growing broiler chickens but not in slow-growing layer chickens. Thomas et al. (2008) observed that starch digestibility in broiler chickens dropped from 5 to 7 d of age, but was restored to a normal high level at 14 d of age.