Mycoestrogen

Mycoestrogens are estrogens produced by fungi. Among important mycoestrogens are zearalenone, zearalenol and zearalanol Although all of these can be produced by various Fusarium species, zearalenol and zearalanol may also be produced endogenously in ruminants that have ingested zearalenone. Alpha-zearalanol is also produced semisynthetically, for veterinary use; such use is prohibited in the European Union.

Mycoestrogens are commonly found in stored grain. They can come from fungi growing on the grain as it grows, or after harvest during storage. Mycoestrogens can be found in silage.

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