Mycotoxin contaminations in commercially used hay

Occurrence and levels of mycotoxins (T-2 toxin, diacetoxyscirpenol, 4-deoxynivalenol, zearalenone, fumonisins, alternariol, sterigmatocystin, emodin, cyclopiazonic acid, ochratoxin A, citrinin, mycophenolic acid, PR-toxin, aflatoxin B 1 and ergot alkaloids) were examined by indirect competitive enzyme-linked immunosorbent assay in field-dried hay from farms in central regions of European Russia. Studies have shown that co-contamination with 5-13 mycotoxins is typical for this forage, and the percentage of 10 mycotoxin complexes is rather high. Complex of 5 components including alternariol, sterigmatocystin, cyclopiazonic acid, emodin and ergot alkaloids was regularly revealed in a half of the taken samples, being the most considerable in this fodder type. The detection frequency of fusariotoxins shown to decrease among: T-2 toxin, diacetoxyscirpenol, 4-deoxy-nivalenol, zearalenone, fumonisins. For the first time wide contamination of dry grassy feeds (more than in half of the analyzed samples) with mycophenolic acid possessing extensive immunosuppressive action is established. Mycophenolic acid inhibits inosine monophosphate dehydrogenase in DNA synthesis during cell growth. PR-toxin was met slightly less often in quantities of 100-1000 mg/kg at an average value of 280 mg/kg. For group of less wide-spread mycotoxins (aflatoxin B 1, ochratoxin A, citrinin) content levels didn’t exceed 100 mg/kg. Accumulation of amounts more than 1000 mg/kg is shown for three fusariotoxins - T-2 toxin, 4-deoxynivalenol, zearalenone and also for alternariol, cyclopiazonic acid, mycophenolic acid, emodin and ergot alkaloids. Combinations of several mycotoxins at high levels are injurious to horses and young ruminants with no paunch function. The mycotoxins with antibacterial activity, particularly emodin, mycophenolic acid and PR-toxin, also cause a misbalance in gut microflora and contribute to other mycotoxin penetration. The possible role of microscopic fungi relating to genera Fusarium, Alternaria, Penicillium, Aspergillus, Chaetomium and Claviceps in hay contamination with mycotoxins is discussed.