|Wu, W - U OF WI, MADISON, WI|
|Krick, T - U OF MN, ST PAUL, MN|
|Xie, W - U OF MN, ST PAUL, MN|
Submitted to: Journal of Natural Toxins
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 16, 1999
Publication Date: N/A
Interpretive Summary: We isolated the molds from high-moisture corn suspected to have caused dairy cattle to refuse to eat, suffer bloating, and diarrhea. The predominant mold we found was called Fusarium. When we grew the mold in the laboratory, we found it produced the family of toxins called fumonisins, and a second known toxin, called moniliformin. We found a previously unknown compound as well but have not yet completely determined its chemical structure. The new compound was toxic in a simple bioassay. But its role, if any, in the cattle sickness is not known. The fumonisins and moniliformin are well known mold toxins. They cause sickness in other animals, but have not been previously associated with these or any other symptoms in cattle. More work will be required to determine if combinations of these substances played an important role in making cattle sick. This information will be useful to veterinarians conducting research with cattle sicknesses.
Technical Abstract: Corn samples suspected of causing refusal-to-eat syndrome in dairy cattle were examined mycologically. Fusarium moniliforme (14 isolates) and F. proliferatum (12 isolates) were the predominant fungi present. These isolates were tested for mycotoxin production on rice at 25 C. Each strain of F. moniliforme produced fumonisin B1 (FB1:378-15,600 ppm) and fumonisin B2 (FB2:2-1050 ppm). Each strain of F. proliferatum produced moniliformin (45-16,000 ppm), FB1 (27-6140 ppm), and FB2 (5-1550 ppm). In addition a new Fusarium metabolite of molecular composition C21H38N2O6 was produced by ten of the F. moniliforme isolates and seven of the F. proliferatum isolates. The metabolite's 1H- and 13C-NMR, HRFAB/MS and IR spectra indicate an alpha amino acid. It is toxic to Lemna minor L. duckweed (LD50 100 ug/mL).