Farmed Laying Hen Bone Health Welfare

Osteoporosis and bone fractures are endemic in laying hens across all housing systems, causing chronic pain and representing one of the most pervasive welfare challenges in egg production.

Key Facts

Over 70% of end-of-lay hens have fractures detectable at slaughter in some studies
Calcium is diverted from bones to eggshell production throughout the laying period
Hens laying 300 or more eggs per year face unprecedented calcium demands compared to wild ancestors
Cage-free systems with perches improve bone strength compared to battery cages through increased activity
Selective breeding for extreme egg production is the root cause — wild jungle fowl lay 15 to 20 eggs per year

Welfare Considerations

Laying hens carry the welfare burden of being selected for egg production rates far beyond their evolutionary biology. The continuous calcium demand from eggshell production depletes bone mineral density progressively, and osteoporotic fractures cause chronic pain that persists through the entire laying period. Improved housing that allows wing flapping and perching improves bone strength, but the fundamental welfare challenge is the breeding for extreme production that makes bone disease nearly universal. Consumer support for slower-production welfare breeds would address the root cause.

What You Can Do

Support welfare certification schemes that assess bone health indicators in laying hen flocks
Advocate for breeding goal reforms that reduce laying rate in favor of bird health and welfare
Choose eggs from slower-laying heritage breeds where available at premium markets
Learn about the connection between extreme egg production and laying hen bone welfare