Don't take a risk; Test for aflatoxin, Bartz says
With the harvest winding down, Wisconsin agriculture officials are urging farmers to protect themselves and their animals by getting corn tested for aflatoxin before using it in feeds.
"Aflatoxin is not common in Wisconsin, but if we were ever going to have it, this would be the year, because of the hot, dry summer we just had," said Nate Bartz, feed specialist with the Wisconsin Department of Agriculture, Trade and Consumer Protection.
Bartz added, "Aflatoxin is a human health risk, an animal health risk, and a financial risk. Dairy farmers who feed their cows corn tainted with aflatoxin could end up dumping a couple of weeks' worth of milk."
Aflatoxins are chemicals produced by two common mold species that infect corn: Aspergillus flavus and Aspergillus parasiticus.
In animals, the toxin may reduce feed efficiency and reproduction, and suppress the immune system.
Aflatoxin-producing molds are associated with very hot, very dry growing seasons, and are usually found in the southern and central regions of the nation. It is less of a risk in Wisconsin, but can occur here.
Bartz recommends that farmers feeding their own corn:
• Scout their corn fields and harvests for olive green or gray-green mold on kernels. Molds do not automatically produce aflatoxins, but the moldier the corn, the higher the risk for aflatoxin contamination.
• Do a quick screening test with a black light, and submit samples to a laboratory if screening tests are positive. A list of laboratories is available at http://datcp.wi.gov/Farms/Drought_2012.
• Assuming tests are negative, dry the corn to 15 percent moisture or less for winter storage, and plan to use it before the following summer. Cool corn to 35-40 degrees Fahrenheit after drying, and attempt to maintain that temperature through the winter. Check the condition of the corn every two weeks.
For detailed information about drawing samples and testing, read the Iowa State University fact sheet at http://www.extension.iastate.edu/Publications/PM1800.pdf.
The U.S. Food and Drug Administration sets levels for aflatoxin in corn, at which the agency may take regulatory action.
Corn for dairy cattle and young animals must contain less than 20 parts per billion aflatoxin. Corn fed to breeding beef cattle and swine and mature poultry must contain less than 100 parts per billion; for finishing swine, less than 200 parts per billion; and for finishing beef cattle, less than 300 parts per billion.
There is no acceptable level for milk.