Dairy Group Issues Warning About Aflatoxin

Handling corn and feed carefully critical for dairymen.

Published on: Oct 5, 2012

A special alert sent out by the Indiana Dairy Producers organization was one of the first to officially say what many are coming to realize – all the talk about the aflatoxin threat was more than talk. There is aflatoxin out there, at least in some fields. As the release from the Indiana Dairy Producers puts it, "Aflatoxin is our reality this year."

If Aflatoxin is there, it's there, and it could show up in the milk. The maximum for aflatoxin in dairy feed is 20 parts per billion. The maximum in milk is 0.5 parts per billion.

The best thing a dairyman can do is dry the corn he's going to feed if he grew it himself at 180 degrees or higher, and dry it quickly to 14% moisture or lower to stop the fungus that produces aflatoxin from growing. Just because Aspergillus, an olive brown mold, is on ears or kernels doesn't mean aflatoxin is present. It doesn't produce it in every case. But it does mean that you ought to test for it, or act as if it is there.

Aspergillus and aflatoxin?  It would take tests for both to know for sure, but the olive-brown mold on these kernels looks suspicious.
Aspergillus and aflatoxin? It would take tests for both to know for sure, but the olive-brown mold on these kernels looks suspicious.

It also means you need to be particular if you're buying corn from another source. Do whatever it takes so you get good testing information and know that the corn coming into your operation is free of aflatoxin.

The worst thing you can do this year is use in-bin drying systems that use low heat. If the Aspergillus is present, it can multiply quickly, and if it is producing aflatoxin, it also can get out of hand quickly.

The rule from grain specialists is to not store wet corn in bins or anywhere else for more than 24 hours, including leaving wet corn on a truck. The fungus can still grow even though the field is harvested. That's because it can attach to kernels.