Effects ofFusarium-toxincontaminated wheat in ruminant nutrition

An experiment was carried out to examine the effects of aFusarium-contaminated wheat grain as a component of the concentrate portion (10 mg deoxynivalenol and 0.76 mg zearalenone, ZON, per kg dry matter) on performance of growing bulls, and on carry over of ZON into tissues and body fluids. In a second study, rumen physiological parameters were investigated in wethers equipped with rumen fistulae. Moreover, the influences of a detoxifying agent (Mycofix®, MP, Biomin GmbH, Herzogenburg, Austria) were considered as an additional experimental factor beside the contamination of the wheat (uncontaminated control wheat,Fusarium-toxincontaminated wheat).The fattening experiment with bulls (n=14 per treatment) covered the live weight range between 244 kg and 460 kg. Daily dry matter intake and live weight gain (kg per animal and day) were 7.40, 7.52, 7.51 and 7.49 and 1.367, 1.296, 1.380 and 1.307 for bulls fed the unsupplemented control wheat, the supplemented control wheat, the unsupplemented andFusarium toxin contaminated wheat and the supplementedFusarium toxin contaminated wheat, respectively. Concentration of ZON and its metabolites in edible tissues were lower than the detection limits of the applied HPLC-method.The results of the rumen physiological investigations revealed that the molar ratios of short chained volatile fatty acids and ammonia concentration in rumen fluid remained unchanged in response to dietary treatments whereas the addition of MP to the diets buffered the postprandial decrease in rumen pH.