Laying hens face severe bone loss from the metabolic demands of intensive egg production. Osteoporosis and fractures cause significant chronic pain in the majority of commercial hens.
Hen bone welfare is the most systematic welfare problem in egg production — affecting virtually every hen by end of lay, driven by the fundamental metabolic conflict between eggshell formation and skeletal integrity. The calcium mobilised for 300+ eggs over a laying cycle comes increasingly from structural bone as the laying year progresses, leaving hens with severely fragile skeletons by the time they are removed from production. The broken legs and wings sustained during rough depopulation handling represent welfare harms inflicted on animals already compromised by chronic osteoporosis. Addressing bone welfare requires both nutritional management during lay and reduced production rate through selection of slower-producing breeds. This is a welfare problem embedded in the genetics of modern commercial hens.