Keel bone fractures affect the majority of laying hens in cage-free systems and cause chronic pain that is emerging as a major welfare priority.
Keel bone fractures cause chronic pain that affects every aspect of hen behaviour. Hens with fractures spend less time at feeders and drinkers due to pain on movement. The fractures often occur at a time when hens are at their most productive, meaning welfare harm coincides with the peak production period. The high prevalence of this condition makes it one of the most significant unresolved welfare problems in commercial egg production, including in cage-free systems that are promoted as high welfare alternatives.