Commercial egg - laying hens have often already begun feather pecking when they are transferred to the egg laying farm from the rearing farm at approximately 16 -- 20 weeks of age .
Plumage quality can then rapidly deteriorate until peak lay at approximately 25 weeks of age .
Commercial egg - laying hens have often already begun feather pecking when they are transferred to the egg laying farm from the rearing farm at approximately 16 -- 20 weeks of age , and plumage quality can then rapidly deteriorate until peak lay at approximately 25 weeks of age .