Keel Bone Fractures in Laying Hens

Keel bone fractures affect up to 80% of laying hens in some flocks, causing chronic pain and welfare compromise.

Key Facts

The keel bone is the breastbone ridge where flight muscles attach in birds
Keel bone fractures affect 50-80% of laying hens in some free-range and aviary systems
Fractures occur from impacts with perches, from falls, and from osteoporosis
Hens with keel bone fractures show pain behaviours and reduced activity
Paradoxically, higher-welfare systems like aviaries can have higher keel bone fracture rates than cages

Welfare Considerations

Keel bone fractures represent one of the most significant emerging welfare issues in laying hen production. The paradox is that systems providing more space and perch access — which are welfare-positive in many respects — can have higher fracture rates due to impacts with perches during landing. This creates a complex welfare trade-off that requires system design improvements rather than a return to caging. Perch height, diameter, and landing zones can be optimised to reduce fracture rates while maintaining the welfare benefits of movement and perch access.

What You Can Do

Support research into housing design changes that reduce keel bone fracture rates
Advocate for keel bone assessment as a welfare indicator in egg certification
Choose eggs from producers actively monitoring and reducing keel bone fractures
Learn about the ongoing research into keel bone welfare and its causes
Understand the complex welfare trade-offs in different housing system comparisons