Overt signs of toxicity to dogs and cats of dietary deoxynivalenol.

Studies were conducted to determine the dietary amounts of deoxynivalenol (DON; vomitoxin) in dog and cat food that are required to produce overt signs of toxicity (e.g., vomiting or reduced food intake). Wheat naturally contaminated with 37 mg of DON/kg was used to manufacture pet foods containing 0, 1, 2, 4, 6, 8, and 10 mg of DON/kg. Deoxynivalenol concentration in pet food following manufacture was unchanged, indicating that the toxin was stable during conventional extrusion processing. Dogs previously fed DON-contaminated food were able to preferentially select uncontaminated food. Dogs not previously exposed to DON-contaminated food consumed equal quantities of contaminated and uncontaminated food. There was no effect of 6 mg of DON/kg on dog food digestibility. Food intake of dogs was significantly reduced by DON concentrations greater than 4.5 +/- 1.7 mg/kg, and DON greater than 7.7 +/- 1.1 mg/kg reduced cat food intake. Vomiting by dogs and cats was commonly observed at the 8 and 10 mg DON levels.