Ammonia in Poultry Houses and Respiratory Welfare

Ammonia generated from poultry litter is a major welfare concern in commercial housing, causing respiratory disease, eye damage and chronic discomfort in housed birds.

Key Facts

Ammonia concentrations above 25 parts per million cause measurable respiratory and eye damage in poultry
UK welfare codes recommend maximum ammonia concentrations of 20 ppm in poultry buildings
Poorly ventilated broiler houses can have ammonia levels exceeding 50 ppm in cold weather when ventilation is reduced
Ammonia-related eye damage (keratoconjunctivitis) affects significant proportions of birds in poorly managed units
Litter moisture content is the primary determinant of ammonia production — dry litter generates far less ammonia

Welfare Considerations

Ammonia exposure in poultry housing is a pervasive welfare problem that is directly preventable through good management. Birds living in high-ammonia environments experience burning of the respiratory tract and eyes, causing chronic discomfort and predisposing them to respiratory disease. In severe cases, eye damage from ammonia can cause blindness. The welfare harm is invisible to consumers but affects hundreds of millions of broilers and laying hens annually. Ventilation management that maintains ammonia below welfare thresholds is achievable and required under welfare codes, but enforcement is inconsistent. Litter quality management that prevents moisture accumulation is the primary control measure.

What You Can Do

Support welfare certification schemes that include ammonia monitoring requirements
Advocate for mandatory ammonia level recording and reporting in commercial poultry units
Choose chicken and egg products from farms with documented ventilation management protocols
Support research into low-ammonia litter management techniques and ventilation system design