High ammonia concentrations in poultry buildings are a common and serious welfare problem, causing eye damage, respiratory disease, and chronic discomfort in millions of birds. Improving air quality is one of the most achievable welfare improvements in the sector.
Ammonia-related welfare harm in poultry is pervasive but invisible to consumers and rarely discussed in welfare debates focused on housing system type. The direct welfare impact — corneal damage, respiratory inflammation, and chronic mucous membrane irritation — affects birds throughout their productive lives in inadequately managed buildings. Corneal necrosis from chronic ammonia exposure is a painful condition that impairs vision and predisposes to secondary infection. At concentrations common in poorly managed facilities, birds live in a state of continuous respiratory irritation equivalent to what humans experience as a persistent eye and throat burning sensation. The economic costs of high ammonia — reduced growth rates, increased respiratory disease, higher medication costs — create potential commercial alignment with welfare improvement, but the costs of monitoring and litter management interventions may not be perceived as justified without regulatory pressure. Ammonia monitoring should be a routine component of all poultry welfare assurance audits, treated with the same seriousness as space allocation and water provision.