Laying Hen Keel Bone Fractures | Animal Welfare Hub

Keel bone fractures are an extremely prevalent and painful welfare problem in laying hens across all non-cage housing systems, representing a major unresolved welfare challenge.

Key Facts

Keel bone fractures affect an estimated 50-80% of hens in enriched colony, barn, and free-range systems by end of lay.
The keel bone is the elongated sternum to which flight muscles attach — fractures cause chronic pain during movement and roosting.
Fractures result from collisions with perches and furniture, osteoporosis from calcium demand of egg production, and falls.
Hens with keel fractures show pain-related behaviour changes detectable through grimace scale and activity monitoring.
Genetic selection, perch design, calcium supplementation, and lighting management all influence fracture prevalence.

Welfare Considerations

Keel bone fractures represent a welfare scandal hidden in plain sight: the majority of free-range hens — the product marketed as high welfare — suffer from chronically painful skeletal injuries that are largely unrecognized by consumers and inadequately addressed by producers. The fracture rate has increased as hens have been selected for higher egg production, creating a biological vulnerability. Addressing this requires genetic selection for bone strength, better perch design, and potentially lower colony sizes.

What You Can Do

Advocate for keel bone fracture prevalence to become a mandatory welfare outcome measure in laying hen assurance schemes.
Support research into genetic selection for keel bone strength as a welfare breeding priority.
Choose eggs from producers that publish and work to reduce keel bone fracture rates in their flocks.
Contact egg retailers to ask about their keel bone fracture monitoring and reduction commitments.