Mold, Yeast & Mycotoxin Testing

A difficult growing season combined with a wet fall is spawning optimal conditions for corn ear mold (fungi) growth. Many molds are harmless however others produce toxins that can cause illness, pregnancy loss and in some cases, death in mature cows. Younger animals or fresh cows are even more vulnerable to problems from eating these types of feeds.

            AgSource offers a number of mold, yeast and mycotoxin tests for both grain and corn silage. The simplest analysis provides a mold and yeast count. If between 100,000 and 10 million mold counts are present, caution is advised in feeding. If more than 10 million are present, feeding may not be recommended; however simple mold and yeast counts may not be sufficient for the 2009 corn crop. 

Molds themselves are not harmful to animals. However, some molds produce an array of chemical products known as mycotoxins. A more expansive AgSource analysis provides the mold count and identification of molds present. This test determines which molds are present and if those molds have the potential to produce mycotoxins that may be harmful to animals. In some cases, mold counts may be high enough to warrant caution; however if the mold is not a toxin producer, feed containing the mold can be safely fed.

While both of the above analyses are valuable, neither identifies if the actual mycotoxin that cause health problems may be present. AgSource's most specific tests identify the presence of the four most common types of mycotoxins. Mycotoxins are secondary metabolites of fungal origin that are toxic to animals and humans.

• Aflatoxin B1, a potent cancer causing agent.
• Zearalenone, associated with infertility and abortion problems in dairy cattle in the midwestern U.S.
• Vomitoxin, known to reduce feed consumption.
• T-2 Toxin, symptoms in cattle are bleeding (uncontrollable, at times, during castration or dehorning), inflammation of the digestive tract, vomiting, diarrhea, decrease in milk production, loss of appetite and feed refusal. 

Under favorable environmental conditions some toxigenic molds can produce mycotoxins on agricultural commodities during plant growth, or after harvest in storage and shipment. Producers with crop insurance that see mold in standing corn should definitely test before harvest. Producers hoping to harvest moldy corn as high moisture corn should also test before harvest. If mold is found in corn in storage, an analysis will determine if adding a binder or dietary dilution is advised or if simply not feeding it is the best alternative.

There are two ways to send your moldy feed sample to AgSource:

• Order mailers from AgSource and simply drop them in the mail
• For faster information, print a Forage Submittal Form from AgSource's website, put your sample in a sealed plastic bag, put both in an envelope and send them to AgSource.

Typically, expect results back in a week after mailing.