High ammonia concentrations in intensive pig housing cause significant respiratory disease and eye irritation, representing a preventable welfare problem at scale.
Ammonia-related respiratory disease in intensively housed pigs is a significant, chronic and largely preventable welfare problem. Pigs in poorly ventilated sheds spend their entire lives breathing air that would be unacceptable for brief human occupancy. The respiratory damage accumulates over weeks and months, causing pneumonia, reduced growth and chronic discomfort. Improving ventilation, reducing stocking density, using bedded systems and managing slurry effectively all reduce ammonia exposure. Outdoor and straw-based systems virtually eliminate the problem. Welfare standards that include air quality monitoring and limits would require meaningful improvement from current common practice.