The effects of protein levels on feather pecking and other behaviors of laying hens

From 9 week to 11 week, 120 Hailan layers were assigned at random to groups of 5 individuals and distributed among 24 pens. They were kept in pens with three protein levels (14%,17%,19%). We observe the feather pecking, feeding groveling, preening, foraging, drinking, standing and walking. we find that protein levels had significant effects on rate of feather pecking (p<;0.01). With the protein levels increasing, the occurrence of groveling and preening were increased, the occurrence of feather pecking, feeding, foraging, drinking, standing and walking were decreased.