Fusarium Mohilforme – Blind Staggers in Horses
Blind staggers (technically known as equine leucoencephalomalacia) occasionally occurs in horses, mules, or donkeys foraging corn left standing in the field after harvest or fed grain or screenings heavily infected with F. moniliforme. The toxins fumonisin B1 and B2 are produced only by certain strains of F. moniliforme. This toxicant is also carcinogenic in laboratory tests.
Fumonisin B1 and B2 have been extracted from corn infected with F. moniliforme. Fumonisin B1 was administered to horses and, within 8 days, the horses exhibited signs of blind staggers. F. moniliforme is common even in food-grade corn and is often abundant in ground feeds and in silage. Growing pigs fed a ration containing 78 to 82 percent corn heavily colonized by F. moniliforme grew as well as the control pigs fed a ration of sound corn. It is therefore likely that fumonisin is not always present when the fungus is, or that pigs are not sensitive to fumonisin B1.
Research on the fumonisin toxins began only recently, and current thought is that concentrations of more than 5 to 10 ppm are necessary for mycotoxicosis in horses and more than 10 to 20 ppm for swine. As with other mycotoxins, various strains of this fungus vary greatly in their toxin producing ability.