Laying Hen Keel Bone Fractures: A Major Welfare Problem

Keel bone fractures affect the majority of laying hens in cage-free systems, representing an urgent and underaddressed welfare crisis.

Key Facts

Studies find keel bone fractures in 50-80% of hens in commercial aviary and cage-free systems
Keel bone fractures cause acute and potentially chronic pain that impairs normal movement and behavior
The keel bone — the large sternum of birds — is subjected to impact forces from landing in multi-tier aviaries
Genetic selection for high egg production may compromise bone density, increasing fracture susceptibility
Perch design, ramp angle, and aviary layout significantly affect keel bone fracture rates
Hens with keel bone fractures show altered movement patterns, reduced perch use, and changes in feeding behavior
Current welfare certification schemes largely fail to monitor or require action on keel bone fracture rates

Welfare Considerations

Keel bone fractures represent an unresolved welfare crisis within the cage-free transition that was supposed to improve hen welfare. The irony is significant: the housing systems adopted to address battery cage welfare failures have introduced a different form of widespread suffering. Pain from keel bone fractures is real — hens show behavioral indicators of chronic pain including reduced activity, altered posture, and avoidance of perches. Addressing this requires integrated action across breeding (bone density selection), housing design (perch and ramp geometry), and management (appropriate stocking density). Welfare certification schemes must incorporate keel bone assessment to drive improvement.

What You Can Do

Support research funding for keel bone fracture prevention in cage-free laying hen systems
Advocate for welfare certification schemes to monitor and require action on keel bone fracture rates
Choose eggs from farms participating in keel bone monitoring programs where available
Consider reducing egg consumption or shifting to plant-based alternatives while keel bone welfare is addressed