Aviary systems are multi-tier housing structures that allow hens to move vertically between levels. They provide perches, dust baths, nest boxes, and foraging areas. Compared to cage systems, aviaries dramatically increase behavioral complexity and expression.
Hens in aviary systems show lower rates of bone breakage from disuse osteoporosis, better muscle tone from movement, and higher rates of dust bathing, perching, and nesting. Feather condition is typically superior to crowded cage systems.
Floor eggs (laid outside nest boxes), smothering, and keel bone fractures remain challenges in aviary management. Training hens to use nest boxes from pullet stage reduces floor eggs. Perch design and height reduce keel bone fracture risk.
High bird density in multi-tier systems requires careful ventilation to control ammonia, dust, and pathogens. Mechanical ventilation with filters and regular litter management are essential. Poor air quality negates welfare gains.
Well-managed aviary systems show comparable or lower mortality to enriched cage systems. Cannibalism risk is managed through light intensity, beak treatment policies, and flock size management. Disease monitoring must be intensive given higher bird-to-bird contact.
Major retailers and food companies globally have committed to cage-free supply chains, driving rapid aviary adoption. Third-party welfare auditing certifies aviary standards. Consumer education on what cage-free means supports demand for higher welfare production.