Effects of vomitoxin (deoxynivalenol) on conditioned saccharin aversion and food consumption in adult rats.

Vomitoxin is a trichothecene mycotoxin that induces feed refusal. Experiment I evaluated the potential aversive action of vomitoxin in a conditioned taste aversion paradigm. Adult male rats were fed either a control chow diet or a diet adulterated with 640 ppm lithium chloride (positive control) or with 2, 4 or 8 ppm vomitoxin and given access to a 0.1% saccharin solution and tap water during three training days. The rats were then shifted to a plain chow diet during 5 extinction days. Vomitoxin (8 ppm) and the positive control diet induced marked taste aversion commencing on the first day of exposure. Rats fed the 4 and 8 ppm vomitoxin diets ate less food only on the first day of contaminated diet exposure. Experiment II evaluated the potential action of vomitoxin on food palatability. Adult male rats were fed a powdered commercial chow for 5 days and then offered, in a preference test, a choice of chow and either: the same chow or chow adulterated with either 0.25, 0.50, 1.0, 2.0, 4.0 or 8.0 ppm vomitoxin. Relative to the total food intakes and the choice ratios (control chow consumed/total chow consumed) of the chow-chow groups, adulteration with 8 ppm vomitoxin resulted in a significant reduction in overall food intake, but not in food choice ratio and this effect of vomitoxin on feed consumption was observed only on day 1 of exposure. Vomitoxin, at 4 and 8 ppm, does not alter food palatability but does induce conditioned saccharin aversion.