Avian mycotoxicosis is considered to be one of the most important problems in the poultry industry. It causes severe losses not only in terms of lost performance, but also as an immunosuppressive agent increasing the bird's susceptibility to diseases and mortality. The gastrointestinal tract represents the first barrier against ingested chemicals, feed contaminants and natural toxins. Following ingestion of mycotoxin-contaminated feed, intestinal epithelial cells can be exposed to toxins. Direct intestinal damage can be exerted by the biological action of mycotoxins.