Approximately 1.6 million tons of feed are fed annually to the roughly 1 million horses living in Germany. However, there is little data available on the quality of the grain used in horse feed production. This is critical because health-hazardous contaminants can be present in the feed (Liesner, 2012).

Various fungi can produce secondary metabolites such as mycotoxins (Samyal & Sharma, 2023). These are formed either in the field or later during storage. Mycotoxins are largely heat-stable and are not actively combated by the immune system (TSK BW, 2020).

In the past, various horse magazines and portals reported on the danger that mycotoxins pose to horses. (Cavallo, 2017, Cavallo, 2025, Sladky, 2016). Among other things, it was reported that horses ate feed containing mycotoxins, which consequently led to elevated liver values. According to the interviewed veterinarians, ZEN, FUM, and DON play a particular role here (Cavallo, 2025).

Research results in veterinary medicine show that mycotoxin contamination is widespread in commercially produced horse feed in Germany. Immediate severe health problems in horses usually become apparent when high amounts of mycotoxins are ingested. Little is known about the long-term consequences of ingesting moderate amounts over an extended period (Liesner, 2012).