Animal & Veterinary
FDA Reminds Horse Owners of Fumonisin Danger
by Walt D. Osborne, M.S., J.D. Assistant Editor
FDA Veterinarian Newsletter 2006 Volume XXI, No V
The Food and Drug Administration (FDA) recently issued a reminder to owners of horses that corn and corn products can contain fumonisins, a group of mycotoxins which is extremely harmful for horses. More than 10 types of fumonisins have been isolated and characterized, and of these, the most prevalent in contaminated corn is fumonisin B1, which is believed to be the most toxic. The dangers are dose-related, and horses and rabbits are the most susceptible of the domestic species. Fumonisins can produce a serious neurologic disease in horses known as leukoencephalomalacia.
Each year, a number of horses die from eating corn or corn byproducts containing fumonisins, which are produced from a mold that resides in corn kernels while still on the corn plant. Typically, fumonisin levels are highest in damaged corn kernels and these damaged corn kernels most often end up in the screenings that separate out when corn is handled. FDA recommends that corn screenings not be used in horse feed since many of the investigated cases of fumonisin poisoning in horses have involved the feeding of corn screenings.
Fumonisins are frequently found in varying amounts in corn and corn byproducts, and they can increase under improper storage conditions. Thus, corn and feed containing corn needs to be kept dry and protected from moisture when stored.
In November 2001, FDA’s Center for Veterinary Medicine (CVM) and the Center for Food Safety and Applied Nutrition jointly issued a final guidance for industry on fumonisin levels in human food and animal feeds. CVM recommended that corn and corn by-products used in horse feed should contain less than 5 parts per million (ppm) of fumonisins and comprise no more than 20 percent of the dry weight of the total ration. This guidance for industry can be viewed on FDA’s Web site at: http://www.cfsan.fda.gov/~dms/fumongu2.html. Additional information about fumonisins is also available at:http://www.fda.gov/cvm/fumonisin.htm.