Genetic and physiological factors influencing feather pecking in chickens

Feather pecking is a major welfare problem in egg production. It may be caused by endogenous (genetic and physiological) and environmental (feeding, density and housing conditions) factors. Despite the number and variety of experiments performed over past years, it is still not possible to define a genetic background for this trait. A possible reason is the complex nature of feather pecking, but also the lack of a homogenous approach in the studies conducted. The present paper summarizes recent findings regarding genetic and physiological components of feather pecking. Furthermore, it emphasizes the need for complex study combining a selection experiment together with the power of molecular biology and bioinformatics.