Occurrence of Mycotoxins in Conserved Grass and Legume Forages – A Systematic Review

Conserved forages are important feed for livestock and equines all over the world. However, contamination with mycotoxins may occur, leading to health issues to the animals and to humans that consume products of animal origin. As information on the occurrence of mycotoxins in conserved grass and legume forages is scarce, a review of the literature published between January 1992 and July 2022 was performed to assess the worldwide occurrence and levels of mycotoxins in hay, haylage, and silage. Zearalenone (ZEN), deoxynivalenol (DON), and aflatoxins (AFs) were the most common mycotoxins found in conserved forage in North America, Africa, and the Middle East, with ZEN and AFs in levels above the maximum levels determined in European Union (EU) regulations for animal feed. Ochratoxin a (OTA) was detected in high levels in conserved forages in Europe. Although other mycotoxins were found, they were detected in lower frequencies and levels. Co-occurrence of mycotoxins was identified in more than half of the studies analyzed. There were few studies carried out in Asia, Middle East, Oceania, and no information was available on Central and South America, reinforcing the need of studies on the issue in these regions.