Keel Bone Fractures in Laying Hens: Scale and Solutions

Keel bone fractures affect the majority of laying hens in commercial production, causing chronic pain that profoundly impacts welfare throughout a laying cycle that typically lasts 72 weeks.

Key Facts

Studies find keel bone fractures in 50-80% of laying hens across all housing systems including free-range
Fractures develop gradually from repeated collision with perches, feeders, and housing structures
Hens with keel bone fractures show reduced activity, altered posture, and pain-related behavioural changes
The keel bone is the sternum — central to locomotion and perching — making fractures particularly debilitating
Genetic selection for bone strength and perch design modifications can significantly reduce fracture rates

Welfare Considerations

Keel bone fractures represent one of the most pervasive and overlooked welfare problems in commercial egg production. Because fractures develop gradually and hens mask pain, the problem went unrecognised for decades. It affects free-range and enriched colony hens as well as caged birds, demonstrating that housing system alone does not solve the problem. Targeted breeding programmes, improved perch design, and lighting management to reduce flying are all evidence-based interventions. Consumer and retailer pressure for welfare-verified eggs should explicitly include keel bone health metrics.

What You Can Do

Support egg producers with documented welfare monitoring programmes that include keel bone assessment
Advocate for keel bone health as an explicit metric in egg welfare certification schemes
Choose eggs from producers using slower-maturing breeds with better bone density
Support research into perch design and flock management practices that reduce fracture incidence