[Impact of atmospheric ammonia on livestock animals--a minireview].

Ammonia is one of the most important trace gases in the air of livestock buildings. Due to its physical and chemical properties and in dependance on the exposure conditions ammonia belongs to the irritant gases with a capability to have a negative impact on the respiratoy mucosa, the eyes and the skin of animals and men. The observed effects are ranging from performance losses over reductions of the mucociliary clearance to disturbences of the epithelial homeostasis including airway inflammations. Furthermore, some livestock species have shown in choice tests their affinity to a low ammoniated environment, where exposure concentrations were considerable lower than the threshold limit values fixed in animal welfare regulations. It can be expected that ammonia will continously be of relevance in future. Therefore, this article gives a short literature-based overview about the biological impact of ammonia on poultry, pigs and cattle.