Keel bone fractures affect over 50% of hens in cage-free systems and are a major unresolved welfare crisis in egg production, causing chronic pain throughout the laying period.
The transition away from battery cages to cage-free systems improved many welfare outcomes for laying hens but inadvertently created a new welfare crisis through keel bone fractures at scale. Hens with fractured keels live with chronic bone pain for the remainder of their laying lives — potentially months. Addressing keel bone welfare requires coordinated investment in breeding programs selecting for bone strength, aviary design improvements reducing fall distances, and management practices that train pullets to navigate complex systems safely before they begin laying.