Keel Bone Fractures in Laying Hens: A Pervasive and Underaddressed Welfare Crisis

Keel bone fractures affect the majority of commercial laying hens in many housing systems, causing chronic pain throughout their productive lives. This is one of the most significant welfare failures in modern egg production.

Key Facts

Keel bone fractures affect 50-80% of hens in cage-free aviaries and 30-50% in enriched cages
Most fractures occur during landing from perches and often go undetected
Fractures cause chronic pain measurable through pain assessment tools validated in hens
Genetics, bone density, housing design, and perch height all contribute to fracture risk
No current housing system has eliminated keel bone fractures — it is an industry-wide challenge

Welfare Considerations

Keel bone fractures represent an extraordinary welfare failure: the majority of the 4 billion laying hens globally may be living with painful bone fractures that are never detected or treated. The transition from conventional cages to cage-free aviaries — driven by welfare concerns — has paradoxically increased fracture rates by providing more perches from which birds fall. Solutions require a multi-pronged approach: genetic selection for stronger bones, housing design that reduces fall distances, nutritional strategies to optimize bone density, and pain monitoring systems to identify affected individuals. This is an active and urgent research and policy area.

What You Can Do

Engage with egg certification bodies about their keel bone fracture reduction plans
Support research into keel bone fracture prevention through hen genetics and housing design
Reduce egg consumption or choose eggs from smaller flocks with more attentive monitoring
Advocate for keel bone fracture monitoring to be included in laying hen welfare audits
Donate to poultry welfare research programs working on this challenging problem