[Effect of ammonia on the pig respiratory system. Study of the dose-response relation].

The effects of ammonia on the respiratory system and somatic growth have been measured in piglets taking into account the interactions with endotoxins from gram-bacteria and dust. Dose-response curves were constructed for the inflammatory reactions induced in nasal cavities, the smooth muscle hyperresponsiveness in the trachea, the permeability of alveolo-capillary barrier, the pulmonary vasomotricity, the cough reflex and the systemic effects. An acceptable level of pollution was proposed.