LEXINGTON, KENTUCKY, U.S. — The past year has presented some challenging weather in the United States, particularly in the Midwest with heavy rain, which has resulted in delayed and/or prevented planting in many areas. Extreme weather conditions and moisture levels can reduce yields and induce plant stress, and they can also lead to future issues for the crop, according to Alltech’s 2019 harvest analysis.

Some of the issues can include molds and mycotoxins. Increased moisture can allow Fusarium molds to flourish, producing a variety of mycotoxins that include deoxynivalenol (DON), fusaric acid, T-2, HT-2 and zearalenone (ZEN).

Alltech said mycotoxins are a concern for livestock producers, as they influence feed quality and animal safety. They are produced by certain species of molds and can have toxic properties that impact animal health and performance.

Samples of the 2019 corn silage from across the United States are currently being submitted to the Alltech 37+ mycotoxin analytical services laboratory, and analysis is indicating the presence of high levels of mycotoxins.

“These levels of mycotoxins found in the 2019 crop are significantly higher than the average values,” said Max Hawkins, nutritionist with the Alltech Mycotoxin management team. “Livestock producers across the U.S. should test their own corn silage to identify the levels of individual mycotoxins and the subsequent risk present to livestock health and performance.”

Results from the 2019 Alltech Harvest Analysis indicate high levels of mycotoxins in corn silage across the United States.

The samples have included an average of 7.13 mycotoxins, with a range of 2 to 14 mycotoxins per sample. In 86.6% of the samples, DON was present; 99.5% contained fusaric acid; and 94.1% tested positive for emerging mycotoxins, including beauvericin, moniliformin, enniatins, phomopsin and alternariol.

“These emerging mycotoxins will add to the risks potentially affecting rumen function, gut health and immune response,” Alltech said. “A point of interest is that ZEN was found in 48.9% of the samples and has become increasingly prevalent over the past two years.”

According to Alltech, mycotoxins are seldom found in isolation, and when multiple mycotoxins are consumed, they may have additive interactions that increase the overall risk to performance and health. As a result, an animal may have a stronger response than what would be expected if it was only experiencing a single mycotoxin challenge.