How ammonia from manure affects livestock welfare in intensive buildings, what the research shows, and what management changes help most.
Ammonia is a significant but often invisible welfare problem in intensive livestock housing. It is produced by the bacterial breakdown of urine and feces and accumulates in poorly ventilated buildings. For poultry, high ammonia levels cause conjunctivitis, corneal damage, and respiratory disease, increasing susceptibility to infection. For pigs, respiratory disease associated with ammonia is a major production and welfare challenge. The irony is that improvements in ammonia control also benefit worker health and reduce local air pollution. Litter management (maintaining dry, low-bacteria bedding), improved ventilation, and lower stocking densities all reduce ammonia.