As harvest progresses, many parts of the Midwest are reporting moldy corn after a growing season marked by heat and stress. Livestock producers need to exercise caution if they are feeding corn possibly tainted by mold.

"Illinois toxicologists report that the moldy corn samples they are seeing appear to be Fumonsin and recommended that producers have tests conducted for aflatoxins, DON, zearlenone, and fumonsins in representative samples of corn," says Michael Hutjens, University of Illinois Extension dairy specialist. "The cost is $65 per sample to screen for four mycotoxins while Fumonsin alone is $30."

Mycotoxin and Fumonsin contamination of corn fed to livestock can cause several problems, espcially in the swine breeding herd and among young pigs. To avoid the problems, producers should have grain tested before feeding. If grain is found to be contaminated, you need to consult with a nutritionist and follow U.S. Food and Drug Administration guidelines for its use. The October issue of Pork magazine also has an article outlining information and guidelines for pork producers.

"Producers need to remember that proper handling of damaged corn is critical as additional growth and mycotoxin occurs if moisture, oxygen and warm temperatures exist during storage and handling," says Hutjens.

Based on FDA guidelines, Gavin Meerdink, Illinois Extension beef and feed-safety veterinarian recommends the following levels in feed:

  • No more than 300 ppb in corn fed to finishing beef cattle; 100 ppb for breeding beef cattle.
  • No more than 200 ppb for finishing swine (animals weighing more than 100 pounds); 100 ppb for breeding swine.
  • No more than 100 ppb for mature poultry.
  • No more than 20 ppb for other animal feeds.
  • Dairy cattle diets should not contain more than 20 ppb in the total ration dry matter.

"This is not because of a health threat to the lactating cow; rather it is related to milk residues," says Hutjens. Aflatoxin is metabolized by dairy cows and some can be excreted in the milk. Milk levels must be less than 0.5 ppb, the maximum that FDA will allow.

"All livestock producers need to be aware of these potential problems and exercise care in feed use of mold-damaged corn," concludes Hutjens.

University of Illinois Extension.