Cage-free systems improve some welfare dimensions while creating new challenges that require management.
The cage-free transition represents genuine progress for hen welfare — the ability to walk, spread wings, and dust bathe are significant improvements over battery cage conditions. However, cage-free systems are not automatically better welfare. Poorly managed cage-free flocks have high mortality from pecking, smothering, and disease. Bone fractures from osteoporosis — a consequence of the calcium demands of high egg production — affect the majority of commercial hens regardless of system. Well-managed aviary systems with outdoor access achieve the best welfare outcomes, but require skill and investment.