Ammonia from poorly managed poultry litter causes respiratory damage and eye problems in chickens and turkeys, representing a major avoidable welfare harm in intensive systems.
Chronic low-level ammonia exposure is a hidden welfare harm: birds in high-ammonia environments show no dramatic clinical signs but experience respiratory inflammation, immune suppression, and painful eye conditions throughout their lives. The conditions develop gradually and in mass-housed flocks often go undetected until welfare is significantly compromised. Proper ventilation design, litter management, and stocking density control are the primary preventive measures — all of which are under farm management control.