Editor’s note: This article is part of TheHorse.com’s ongoing coverage of topics presented at the 2012 Kentucky Equine Research Conference, held May 17-18 in Lexington, Ky.

For years, researchers, scientists, and veterinarians have advised horse owners to be cautious and aware of mycotoxins in horse feeds, forages, and pastures. And while these tiny toxins can cause serious illnesses in horses, they can also be difficult for owners to understand.

At the 2012 Kentucky Equine Research Conference, held May 17-18 in Lexington, Ky., Ramesh C. Gupta, DVM, PhD, Dipl. ABT, professor and head of the toxicology department at Murray State University’s Breathitt Veterinary Center, in Hopkinsville, Ky., gave an overview of mycotoxins that affect horses and the clinical signs, diagnostics, and treatments associated with mycotoxicosis.

Gupta explained that mycotoxins–dangerous toxins exuded from molds–can form or develop during any stage of the food production chain, from when the host plants are germinated all the way through when the finished product is consumed. There are more than 100 species of mycotoxin-producing fungi worldwide, he said, noting that the species can produce one or multiple types of toxins.

There are five major mycotoxin groups that affect horses, Gupta noted, and he described each in detail.

Aflatoxins

Gupta explained there are four major aflatoxins that affect horses: aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), and aflatoxin G2 (AFG2). Aflatoxins, he said,