While excessive moisture may not be a problem for many in the Midwest this harvest season, mold and toxins aren’t something to sleep on this year.
If mold is present, there is an increased chance that mycotoxins will be present.
“Mycotoxins are not automatically produced whenever grain becomes moldy,” according to research from Iowa State University’s Grain Quality Laboratory. “However, from a risk viewpoint, the likelihood of toxins is greater in damaged kernels than in sound kernels.”
There are inherent health risks to those handling the grain when it comes to mold and other toxins. The University of Minnesota said in a report recently reviewed by Alfredo DiCostanzo, who now works for the University of Nebraska, that compromised grain consumed by livestock creates some of the bigger health risks that are easily avoidable.
“Moldy grain can harm cattle production with Mycoses and mycotoxicoses,” they said. “Respiratory problems aren’t clearly reported in cattle, but you should consider them when cattle have reduced dry matter intake or breathing problems from feed. Molds rarely cause systemic disease, but have caused abortion and blood poisoning in cattle.”
Mycotoxins are also able to cause vomitoxin and F-2 toxin.
To determine what could be infected grain, field conditions are the best place to start. If there has been stalk rot or ear rot, the odds are increased for impacted grain. A lower-than-expected bushel weight and a musty odor are also signs of mycotoxins in the field.
In addition to medical concerns, mold will lower the nutritional value of the feed.
“Animal production may decline after eating moldy feed,” Minnesota said. “Many molds produce substances with antibiotic activity, which can alter rumen microflora if eaten by cattle. Thus, you can discount the nutrient value of grain by 5 to 10% if it has 1 to 5 million cfu/g (colony forming units per gram).”
Spore counts on grain is common, but often they are less than 10,000 cfu/g.
To avoid the spread of mycotoxins, the first step is to avoid cross-contamination. Don’t mix potentially “dirty” grain with grain that is unaffected.
It’s a good practice for trucks and containers to be completely emptied between loads, they said. Ideally, they are swept too. Mixing occurs during loading and unloading.
Drying grain down as quickly as possible is helpful as molds thrive in high-moisture environments. Keep an eye on storage areas and ensure there is proper temperature and humidity control throughout the winter. Any rapid fluctuations can cause issues for grain.
The best practice is simply to dry the grain, have a clean storage area, and maintain a climate that is hostile to molds.