Aspergillus is found worldwide and causes damage to other crops such as peanuts, cotton seed, and tree nuts. Aflatoxin is a highly poisonous and carcinogenic substance that when fed to farm animals can cause poor weight gains, reproduction difficulties and even death. However, FDA regulations allow certain amounts to be fed to livestock and poultry. Corn must not exceed 100 ppb aflatoxin if it is destined for breeding cattle, breeding swine or mature poultry. There is marked variation in susceptibility of farm animal species to aflatoxin, but in all species studied the young are far more susceptible than mature animals.
Sheep appear to be the most resistant of the farm animals.
In most species studied the first clinical signs of aflatoxicosis are lack of appetite and weight loss. General unthriftiness may be the only sign of disease until a few days before death when animals become dull, develop nervous signs and are recumbent. The most important pathology change is damage to the liver. The livers from affected animals are pale or discolored and the liver damage is accompanied by accumulation of fluid in the body cavities and about the visceral membranes. Researchers with the Agriculture Research Service have released aflatoxin resistant germ plasm to commercial corn seed companies.