**Preface to "Mycotoxins Occurence in Feed and Their Influence on Animal Health"**

A large percentage of plant materials and plant-based products used in feed production can be contaminated with mycotoxins (undesirable substances), which pose health risks for humans and different livestock species. The symptoms and adverse health (toxicological) effects associated with exposure to high doses of many mycotoxins are well known. According to the hormesis paradigm, greater attention should be paid to the risks resulting from exposure to low mycotoxin doses that are often encountered in feedstuffs. Dysfunctions in mammals exposed to pure parent compounds, without metabolites or modified mycotoxins, constitute a very interesting research problem.

Most mycotoxins are absorbed in the proximal section of the small intestine, due to considerable physiological variation between intestinal segments. Next, mycotoxins enter the bloodstream, and blood parameters can be used for non-invasive assessment of the animals' health status and for identifying new biomarkers of pathological states. Most targets are cells, where mycotoxins and their metabolites can cause certain pathological states. These mycotoxins not only regulate enzyme metabolism or gene expression, but can also act as ligands that bind to specific receptors on cell membranes or in nuclei, thus participating in signal transduction.

For this reason, the presented studies in the Special Issue of Toxins evaluated selected body systems and functional biomarkers of animals for different doses of mycotoxins causing mycotoxicosis. I hope that the knowledge gained will deepen our knowledge about the effects of mycotoxins on animal health and facilitate decision-making in risk management.

> **Maciej Gajęcki, Magdalena Gajęcka , Łukasz Zielonka** *Editors*
