Farmed Hen Bone Health: Osteoporosis and Fracture Prevention

Bone fractures are epidemic in laying hens due to calcium depletion from egg production and lack of exercise, causing widespread undetected pain across the industry.

Key Facts

Up to 30% of commercially housed hens have bone fractures at time of slaughter
Laying hens produce up to 300 eggs per year, depleting skeletal calcium reserves
Medullary bone — a calcium reservoir — is depleted and rebuilt repeatedly during lay
Cage housing prevents exercise needed to maintain bone density in load-bearing bones
Keel bone fractures affect 50-80% of hens in some production systems and cause chronic pain
Aviary systems with perches reduce fracture rates but require careful design to prevent collision injuries

Welfare Considerations

Hen bone welfare is one of the most significant and underappreciated welfare problems in commercial egg production. The combination of extreme laying rates and restricted movement creates an epidemic of painful fractures that hens must endure silently throughout their productive lives. Keel bone fractures — breaks to the breastbone — are particularly prevalent and cause persistent pain that alters feeding and resting behavior. While cage-free systems improve bone density through exercise, poorly designed aviaries introduce new fracture risks from falls and collisions. Solving hen bone health requires both housing reform and genetic consideration.

What You Can Do

Choose eggs from systems with documented lower keel bone fracture rates
Support research into hen genetics that reduce fracture susceptibility at high laying rates
Advocate for mandatory bone welfare monitoring in commercial laying hen flocks
Reduce egg consumption to lower demand on systems with endemic bone health problems
Support laying hen welfare organizations working specifically on fracture prevention