As the outside temperature warms up, it is no longer possible to keep grain stored at a temperature of 50° F. This means that mycotoxins can now be produced in stored grain, explains Hans H. Stein, head of the Monogastric Nutrition Laboratory at the University of Illinois.

So keep an eye on grain quality coming out of the bins and try to keep moisture content below 14% to reduce the risk of mycotoxin production in the grain.

“Contaminated grain needs to be cleaned and dried and, if possible, it should be mixed with non-contaminated grain before usage to reduce the level of mycotoxins in the finished feed to levels that will not cause production problems,” he says.

Mycotoxins are produced by mold in grain, but mold presence doesn’t always lead to growth of mycotoxins. But just because mold isn’t visibly present doesn’t mean that the grain is free of mycotoxins either.

If a load of grain is suspected of mycotoxin contamination, test it for vomitoxin and zearalenone, the two most common toxins in the corn crop of 2009, Stein says.

If zearalenone is detected in the grain, don’t feed it to breeding animals, Stein advises, because it usually leads to reproductive problems. However, grain containing up to 2 ppm of zearalenone can be fed to grow-finish pigs.

Vomitoxin in grain will lead to feed refusals, vomiting and reduced growth performance even at levels as low as 2 ppm. If the concentration of vomitoxin is at or above 2 ppm, contaminated grain needs to be blended with non-contaminated grain, according to Stein. The complete feed should contain no more than 1 ppm vomitoxin.