Article Master

25 Mycotoxins are toxigenic metabolites of fungi. They occur worldwide and are a potential risk to humans and animals when feeds and cereals are contaminated. Their importance and occurrence have been recognised for over 30 years. Following the eating of contaminated foods and feeds, so called mycotoxicoses are observed in animals. These intoxications should be differentiated from mycoses, which are caused by active invasion of growing fungi into living tissues in a way that results in destruction of the tissue. In dairy cows the course of mycotoxicoses is acute or chronic, depending on the amount of mycotoxin ingested. Furthermore, mycotoxins depress the cow’s immune system making her more susceptible to infections. Mycotoxin contaminated feedstuffs are a potential risk to the consumer because of residues in meat and milk products. Specific mycotoxins affect certain organs, such as the liver, kidney and brain, or mucous membranes of the gastrointestinal or genital system. In this article a general view of the most important moulds and mycotoxins and their effects on dairy cows will be considered and cases studies from Austrian dairy herds are described. Feeding studies with zearalenone and vomitoxin contaminated feedstuffs and their effect on dairy cows are also reported. Based on the climatic conditions the most important mycotoxins in Austrian foodstuffs are as follows: Fusarium toxins (deoxynivalenol = vomitoxin and other trichothecenes). These affect the mucous membranes of the digestive tract. Zearalenone, causing infertility. Aflatoxins (liver damage) occur in imported feedstuffs (peanut meal, soybean meal). Ochratoxin A (kidney problems) are of lesser importance in terms of economic losses in dairy herds.