EFFECT OF SUBCLINICAL LEVELS OF T-2 TOXIN ON THE BOVINE CELLULAR IMMUNE-SYSTEM

  • 1 January 1984
    • journal article
    • research article
    • Vol. 48  (3) , 308-312
Abstract
The effect of subclinical levels of mycotoxin T-2 on the cells of the bovine immune system was investigated in 2 in vivo experiments. In experiment 1, 5 calves were orally dosed with 0.3 mg/kg per day of T-2 toxin for 56 days, and 5 calves were pair fed controls. The neutrophil function, as measured by nitroblue tetrazolium reduction, was reduced in the mycotoxin treated calves. The cutaneous reaction to intradermally infected phytohemagglutinin was reduced in the T-2 toxin treated calves. B-cell (SIg+) numbers increased slightly, but T-cell (PNA+) numbers were not affected during the experimental period. In the 2nd experiment, 6 calves were given 0.5 mg/kg per day T-2 toxin orally for 28 days, and 6 calves were pair fed controls. B-cell numbers, and the response of a B-cell enriched fraction to phytohemagglutinin, increased after toxin administration. T-cell numbers, and the response of a T-cell enriched fraction and the whole mononuclear cell population to phytohemagglutinin, was reduced only on day 19 posttoxin administration. The in vitro (T-2 toxin) exposure of the mononuclear cell population, B-cell enriched, or T-cell enriched fraction reduced their lymphoblastic response to mitogens. A 50% reduction was induced by as little as 1.4 ng/ml of T-2 toxin.