Laying Hen Bone Health and Keel Bone Fractures

The prevalence and welfare impact of keel bone fractures in laying hens, and housing and management changes that reduce this widespread injury.

Key Facts

Keel bone fractures affect 50-80% of laying hens in many commercial flocks, making this the most common farm animal welfare problem by number
Fractures cause chronic pain that affects feeding, movement, and overall quality of life
Colony cages reduce some keel bone fracture rates compared to enriched cages but create other welfare problems
Perch design, height, and positioning significantly affect fracture risk during landing and roosting
Selective breeding for bone strength is being explored as a longer-term solution to the keel bone crisis

Welfare Considerations

Keel bone fractures in laying hens represent arguably the largest single source of unaddressed chronic pain in farmed animal welfare globally — affecting hundreds of millions of birds at any given time. The fractures are painful, common, and poorly understood by consumers who associate welfare concerns with cage confinement rather than this invisible injury. Even cage-free and free-range systems show high fracture rates from collisions during flight and landing. Addressing keel bone welfare requires improved perch design, selection for bone strength, and better monitoring and intervention protocols on commercial farms.

What You Can Do

Support egg certification schemes that explicitly track and report keel bone fracture prevalence
Advocate for research funding to address keel bone fractures as a priority welfare problem
Engage with egg producers and retailers about their monitoring and response to keel bone injuries
Choose eggs from flocks that have demonstrated lower fracture rates through welfare monitoring programs
Learn about keel bone welfare science to understand that cage-free does not automatically mean better welfare in this regard