Laying Hen Keel Bone Fractures: A Welfare Crisis in Cage-Free Systems

Keel bone fractures affect the majority of laying hens in commercial production, causing chronic pain that represents one of the largest unaddressed welfare problems in animal agriculture.

Key Facts

Keel bone fractures affect 50-80% of laying hens in cage-free and free-range systems, and 30-50% in enriched cages
The keel bone — the sternum of birds — is particularly vulnerable during flight landings and falls from perches
Research confirms that hens with keel bone fractures show altered behavior and pain responses
Selective breeding for production traits may have inadvertently reduced bone mineral density, increasing fracture risk
Perch design, height, and substrate type all influence fracture rates — welfare-optimized designs reduce risk
There is no routine treatment for keel bone fractures in commercial flocks — affected birds live with the injury

Welfare Considerations

Keel bone fractures represent a welfare crisis hiding in plain sight. The transition to cage-free systems — widely celebrated as a welfare improvement — has in some ways worsened this specific problem by giving hens the ability to fly to perches and then land heavily. The majority of commercial laying hens are living with painful broken bones for significant portions of their productive lives. This is not a peripheral welfare issue but a central one affecting billions of birds annually. Addressing it requires coordinated action on genetics (breeding for stronger bones), housing design (perch height, substrate softness), and management. The fact that this massive welfare problem receives far less attention than it deserves reflects how easily animal suffering can remain invisible at industrial scale.

What You Can Do

Support welfare certification schemes that include keel bone fracture monitoring and reduction requirements
Advocate for keel bone fracture to be treated as a priority welfare indicator in laying hen standards
Support research into genetics, housing design, and management practices that reduce fracture risk
Reduce egg consumption or shift to plant-based alternatives
Raise awareness that cage-free does not mean welfare-problem-free in laying hen production