Fusarium Ear Blight - Effect in Human and Animal Health

Effect in Human and Animal Health

Many Fusarium species (including F. graminearum) produce mycotoxins—fungal chemicals that are harmful to animals. These chemicals may operate in nature to disable plant defense mechanisms or to defend the fungus against other microorganisms. The major toxin produced by F. graminearum in association with FHB in wheat and barley is deoxynivalenol (DON). DON is sometimes called vomitoxin because of its deleterious effects on the digestive system of swine and other monogastric animals. DON disrupts normal cell function by inhibiting protein synthesis. Humans consuming flour made from wheat contaminated with DON will often demonstrate symptoms of nausea, fever, headaches, and vomiting.

DON contamination is measured in parts per million (ppm). DON levels in FHB-infected wheat are frequently quite high (>20 ppm). The USDA recommends that DON levels in human foods not exceed 1 ppm. However, individual grain buyers may have lower tolerances of DON in purchased grain. The FDA has various guideline levels of DON permissible in livestock feed: ruminant animals, such as feeder cattle, are the most tolerant, while swine have the highest sensitivity to DON in livestock feed, with pigs refusing feed containing 1ppm of DON.

The mycotoxins produced by F. graminearum may pose a serious threat to human and domestic animal health. Grain that has been infected with the fungus may become incorporated into our staple diets. Strains of the fungus from different countries produce different toxins, some potentially more potent and dangerous than those from strains currently in the United States.