Zearalenone (ZEA), also known as RAL and F-2 mycotoxin, is a potent estrogenic metabolite produced by some Gibberella species. Several Fusarium species produce toxic substances of considerable concern to livestock and poultry producers, namely deoxynivalenol, T-2 toxin, HT-2 toxin, diacetoxyscirpenol (DAS) and zearalenone. Zearalenone is the primary toxin, causing infertility, abortion or other breeding problems, especially in swine.