Feeding trials with vomitoxin (deoxynivalenol)-contaminated wheat: effects on swine, poultry, and dairy cattle.

Nutritional and toxicologic feeding trials with 3 species of farm animals demonstrated that decreased feed consumption and reduced weight gains in pigs are the main effects of ingestion of a diet with low vomitoxin (deoxynivalenol; DON) content, eg, 2 mg of DON/kg of feed, ie, 2 ppm. The feeding trials indicated that swine can ingest up to 2 mg of DON/kg of feed without serious adverse effects. Poultry can tolerate at least 5 mg of DON/kg feed. In fact, at concentrations up to 5 mg of DON/kg feed, some beneficial effects on poultry were observed. In dairy cattle, feed consumption decreased slightly when a wheat-oats diet containing 6 mg of DON/kg was fed at the rate of 1% of body weight/day, with hay offered ad libitum. In surveys of Canadian grains carried out during the past 3 years, the DON content (maximum of 8.5 mg/kg) in eastern Canadian wheats probably was not high enough to account for reports of feed refusal, vomiting, and reproductive problems in livestock operations. This conclusion is based partly on the fact that even at the highest concentrations of DON found in wheat, formulated diets comprise, at maximum, about 70% to 80% wheat. Consequently, the actual DON content of diets fed to farm animals would be much lower.