Farm Animal Welfare

Keel Bone Fractures in Laying Hens

Keel bone fractures affect the majority of laying hens in aviary and free-range systems, causing chronic pain that is widely underdiagnosed; it is one of the most significant welfare problems in egg production.

Key Facts

Up to 80% of laying hens in free-range and aviary systems sustain keel bone fractures
Fractures occur from collision with equipment during flight and from falls
Hens with keel bone fractures show pain sensitivity indicators and altered behaviour
Breeding for keel bone density is being actively researched as a mitigation strategy

Welfare Considerations

The keel bone fracture problem illustrates how welfare improvement in one area can create challenges in another: aviary housing improves natural behaviour expression over cage systems but imposes higher keel fracture prevalence. Chronic keel bone fracture pain represents a significant ongoing welfare cost that is invisible to consumers and under-appreciated by producers. Systematic pain assessment and selective breeding for keel bone integrity are priority interventions.

What You Can Do

Support research into keel bone fracture prevention through housing design and breeding
Advocate for keel bone fracture monitoring as a mandatory welfare indicator in laying hen assurance schemes
Raise awareness that free-range and aviary systems, while preferable to cages, have unresolved welfare challenges