Aviary housing systems for laying hens offer significant welfare improvements over cages by allowing natural movement, but present new challenges around smothering, keel bone fractures, and management.
Aviary housing represents an important step forward for laying hen welfare by allowing natural movement and behavioral expression impossible in cages. However, the transition from cage to cage-free has not always delivered expected welfare gains because aviary system design and management profoundly affect outcomes. Keel bone fractures — painful chest bone breaks from collisions and falls — affect a substantial proportion of hens in poorly designed aviaries. Smothering risk from hen piling requires active management through lighting and physical interventions. The welfare potential of aviary systems is substantially higher than cages, but realizing that potential requires investment in design, management training, and outcome monitoring that not all producers undertake.