Keel bone fractures affect the majority of laying hens in both cage-free and conventional systems, causing chronic pain that represents one of the most significant welfare problems in poultry.
Keel bone fractures represent a hidden welfare crisis because they are invisible during routine husbandry, affect the majority of hens, and cause chronic pain throughout the productive lifespan. Hens with fractured keels show behavioral changes including reduced movement, preference for floor over elevated perches, and reduced engagement with enrichments — but these signs are easily attributed to individual behavioral variation. Welfare assessment through palpation or post-slaughter examination reveals the true scale of the problem. The welfare significance is substantial: a hen with a fractured keel experiences chronic pain for months. Solutions require a combination of genetic selection for bone strength, system design that reduces impact velocities, and management practices that protect hens during the critical early weeks when fractures are most common.