Respiratory disease is among the most common and painful conditions affecting commercial poultry. Overcrowding, poor ventilation, and pathogen pressure combine to create chronic welfare problems for billions of broiler and layer hens.
Chickens experiencing respiratory disease suffer from laboured breathing, lethargy, swollen sinuses, and secondary immune suppression. In highly stocked commercial environments, disease spreads rapidly before clinical signs are detected. Ammonia-induced damage is both painful and silent — welfare assessments using ammonia monitoring are a key tool. Lower stocking densities, improved litter management, and better ventilation reduce disease burden significantly. Welfare-centred respiratory health programmes combine vaccination, environmental management, and clinical monitoring to minimise suffering at scale.