The fumonisins include two principal toxins produced by Fusarium moniliforme. Signs of acute toxicity in growing and adult pigs are primarily related to the respiratory system and include dyspnea, cyanosis, weakness and death within four to ten days. Pulmonary lesions include marked pulmonary edema and hydrothorax. Pregnant sows that survive acute toxicity frequently abort in the days following their recovery. Growing pigs that survive the acute syndrome suffer from clinical signs related to a hepatotoxicosis. Their lesions may include icterus, hepatic necrosis, and megalocytosis. Differences in lesions and clinical presentation seem to be dose related.
Recent research has demonstrated that fumonisins decrease the ability of intravascular macrophages to clear blood-borne bacteria in swine, thereby potentially increasing susceptibility to respiratory disease. Fumonisin is a well known cause of leukoencephalomalacia in horses and is carcinogenic in humans at high concentrations.