Mycotoxins in feeds and their fate in animals: a review

Mycotoxins are secondary metabolites secreted by moulds, mostly belonging to the three genera Aspergillus, Penicillium and Fusarium. They are produced in cereal grains as well as forages before, during and after harvest, in various environmental conditions. Due to the diversity of their toxic effects and their synergetic properties, mycotoxins are considered as risky to the consumers of contaminated foods. Mycotoxin metabolism is complex and involves pathways of bioactivation and detoxification in both humans and animals. Detoxification occurs via biotransformation mediated by enzymes in the host cells and in the digestive microbial flora. Some of the toxins or their metabolites may become fixed in animal or human tissues. However, most are eliminated in the urine, faeces and milk. In animals, toxicity is generally revealed as chronic minor troubles and only rarely causes death. The presence of mycotoxins in feeds may decrease feed intake and affect animal performance. In addition, the possible presence of toxic residues in edible animal products (milk, meat, offal), may have some detrimental effects on human health. Maximum acceptable doses in feeds and milk have been set for certain mycotoxins by international authorities. The potential risks of mycotoxins may be controlled by checking plant material for fungal contamination, by improving methods of cultivation, harvest and storage, by eliminating or diluting toxins from the contaminated food or feeds, and by using adsorbents to reduce the bioavailability of toxins in the digestive tracts of animals. These measures will be assessed in the present paper.