Laying Hen Keel Bone Fractures: A Major Welfare Problem

Keel bone fractures affect the majority of laying hens in commercial systems and cause significant chronic pain.

Key Facts

Prevalence of keel bone fractures in commercial laying hens ranges from 50-80% in cage-free systems
The keel bone is the breastbone to which flight muscles attach — fractures occur during perch collisions
Fractured keel bones cause chronic pain affecting feeding behaviour, movement, and social interaction
Cage-free systems have higher keel fracture rates than cages, presenting a complex welfare trade-off
Selective breeding for stronger keel bones and better perch design can significantly reduce fracture rates
Gentle ramp access, lower perch heights, and cushioned perch surfaces reduce collision-related injuries

Welfare Considerations

Keel bone fractures represent one of the most significant welfare challenges in cage-free egg production. The move from cages to cage-free systems generally improves hen welfare — providing space, movement, and natural behaviour opportunities — but simultaneously increases keel fracture rates due to collisions with perches and structures during flight and landing. This is not a reason to return to cages, but a welfare problem requiring active solution. Perch design, height, angle, and surface material all affect fracture risk. Selective breeding for keel bone strength and bone density is a long-term solution that the industry is beginning to implement. Regular assessment of keel bone health in flocks provides data to drive management improvements.

What You Can Do

Choose eggs from systems with explicit keel bone welfare management programmes
Support industry efforts to develop perch systems that reduce keel bone fracture rates
Advocate for keel bone fracture assessment to be included in flock welfare auditing
Engage egg producers about their keel bone reduction strategies and breeding programme commitments
Support research into perch design, hen genetics, and management approaches to reduce fractures