Research into bone mineral density in laying hens has revealed the biological mechanisms behind epidemic osteoporosis and keel fractures, pointing toward prevention strategies.
Bone mineral density science in laying hens reveals a welfare problem built into the biology of modern high-production laying strains. The cyclic depletion of structural bone calcium to maintain medullary bone reserves for eggshell formation progressively weakens the skeleton over the laying period - a process that is exacerbated by the extreme egg production rates of commercial strains. Exercise access through perches and platforms in non-cage systems maintains muscle mass that supports skeletal integrity, but cannot fully compensate for the calcium loss inherent in high-frequency laying. The scientific understanding of bone mineral density mechanisms provides targets for multiple intervention points: breeding, nutrition, housing, and management, each of which can contribute to reducing the epidemic of osteoporosis in laying hens.