Laying Hen Osteoporosis and Bone Welfare

Laying hens suffer from chronic calcium depletion due to high egg production rates, leading to osteoporosis and bone fractures that cause significant ongoing pain.

Key Facts

A modern laying hen produces over 300 eggs per year — far beyond wild jungle fowl rates
Each egg contains approximately 2g of calcium that must come from skeletal reserves
Over 50 percent of hens in some studies show osteoporosis by end of lay
Bone fractures, especially keel bone fractures, affect 50 to 80 percent of hens in some flocks
Keel bone fractures cause chronic pain that alters behavior and reduces welfare

Welfare Considerations

The welfare impact of keel bone fractures in laying hens is one of the most significant underaddressed problems in poultry welfare. Fractures occur when hens fall or collide with enriched cage or aviary structures, causing breaks in the sternum that heal incorrectly, leaving permanent deformity and chronic pain. The prevalence of keel bone fractures across welfare systems — including free-range and organic — indicates that genetics, calcium metabolism, and housing design all require attention. Hen welfare at end of lay is also poorly addressed as spent hens are rarely given the same welfare consideration as younger birds.

What You Can Do

Choose eggs from producers committed to addressing keel bone fracture through genetic and housing improvements
Support research into keel bone fracture prevention in aviary systems
Reduce egg consumption as a direct welfare improvement for laying hens
Advocate for welfare standards that address keel bone fracture specifically
Engage egg producers about their keel bone monitoring and improvement programs