Laying Hen Bone Health and Osteoporosis

Laying hens face a hidden but severe welfare problem: osteoporosis caused by calcium depletion from constant egg laying, leading to fractures and bone pain.

Key Facts

Over 30% of laying hens sustain bone fractures during their laying life, often undetected
Medullary bone provides calcium for eggshell formation but depletes structural bone
Keel bone fractures affect up to 50-80% of hens in some cage-free systems
Fracture rates are lower in cage systems but cage systems prevent natural behavior
Pain from keel bone fractures affects feeding, movement and overall hen welfare

Welfare Considerations

The pressure to produce an egg almost every day has made modern laying hens prone to a form of production disease: osteoporosis so severe that bones fracture during normal activity. This welfare problem exists across all production systems, from battery cages to free-range, though the causes differ. In cages, disuse osteoporosis occurs due to immobility. In cage-free systems, keel bone fractures happen from perch falls and collisions. Neither system has adequately solved this welfare challenge.

What You Can Do

Choose eggs from farms with documented keel bone fracture monitoring programs
Support research into laying hen genetics that balance productivity with bone health
Advocate for perch design standards that reduce keel bone injury risk
Consider reducing egg consumption as part of a lower-impact diet