Keel bone fractures affect the majority of laying hens in many commercial systems, causing chronic pain and representing one of the most significant unresolved welfare problems in egg production.
Keel bone fractures represent the most widespread and serious unresolved welfare problem in modern egg production. The irony is that systems introduced to improve welfare over battery cages - particularly multi-tier aviary systems - have been associated with high fracture rates through the collision and fall hazards they create. The suffering caused by chronic fractures is substantial, with affected hens showing behavioural changes consistent with ongoing pain throughout the remainder of their laying lives. Addressing keel bone welfare requires coordinated intervention across genetics, housing design, and management, with no single solution yet proven effective at scale.