Severe feather pecking is an injurious behaviour where hens vigorously peck at and pull out the feathers of other birds. It is a widespread and serious welfare concern in the egg industry. The pulling out of feathers is painful for the recipients, which then face a higher risk of receiving further pecking. It can lead to feather damage, extensive feather loss, wounds, cannibalism and death.
Severe feather pecking, vent pecking and cannibalistic pecking occur in all production systems, but are more widespread in cage-free systems where birds are kept in large groups because the birds that are pecking have access to a lot more birds.
Beak trimming and reduced lighting levels are used in all production systems as routine measures to control severe feather pecking. However, severe feather pecking is multifactorial, and is affected by genetics, the environment, and nutrition. Recent research suggests that there is a small proportion of birds which initiate severe feather pecking, and that the behaviour may then spread throughout a flock. Therefore, the risk of severe feather pecking does not appear to vary between housing systems. Rather, it is the spread of the behaviour which differs.
Managing the risk and spread of severe feather pecking is critical in determining hen welfare. Mortality is highly variable in cage-free systems. More research, as well as the refinement of system design and management strategies are needed to control and prevent severe feather pecking and associated mortality.
Severe feather pecking is a heritable trait. Current studies are investigating selecting against traits which may predispose birds to initiate severe feather pecking. Good management, which includes adequate nutrition, providing high-fibre diets and suitable flooring material from an early age, no sudden changes in diet or environmental conditions, minimising stress and fear in the birds, appropriate rearing conditions, good husbandry, and matching rearing and laying environments should be paired with genetic selection programs. This approach has the potential to reduce the prevalence of severe feather pecking.
For more information, RSPCA Australia’s scientific report on layer hens may be accessed here: https://www.rspca.org.au/layer-hen-welfare