Mycotoxin Survey in US corn: May 2019 update

Our May update from the annual Biomin® PROcheck mycotoxin survey in corn harvested in 2018 includes 620 samples from 30 states. Of the sample pool 79% are corn samples (425 samples), 20% are corn silage (125 samples), and 11% are corn by-product (70). Below we discuss trends of each of these feed ingredients regarding mycotoxin prevalence and contamination levels. 

Corn

  • 98% of ground corn samples are positive for at least one mycotoxin, vs 89% in 2017
  • 72% of samples have more than one mycotoxin, vs 47% in 2017
  • Aflatoxin prevalence in dry corn increased to 9% vs 4% in 2017, with average contamination levels increasing over four fold.
  • Deoxynivalenol (vomitoxin) prevalence rose to 77% vs 70% in 2017, with average contamination level increasing by 44%
  • Fumonisin prevalence jumped to 78% vs 52% in 2017, with average contamination levels increasing by 42%
  • Zearalenone prevalence increased to 44% vs 25% in 2017, with average contamination levels remaining steady

Corn By-Product

  • 96% of samples are positive for at least one mycotoxin, vs 100% in 2017
  • 90% of samples have more than one mycotoxin, vs 94% in 2017
  • Aflatoxin prevalence decreased to 1% vs. 9% in 2017, both years with similar and low contamination levels.
  • Deoxynivalenol (vomitoxin) prevalence decreased slightly to 94% vs 99% in 2017, with average contamination level increasing by 46%
  • Fumonisin prevalence is 88% vs 91% in 2017, with average contamination levels remaining steady.
  • Zearalenone prevalence is 84% vs 80% in 2017, with average contamination level nearly 2.7 fold

Corn Silage

  • 93% of samples are positive for at least one mycotoxin, vs 91% in 2017
  • 65% of samples have more than one mycotoxin, vs 30% in 2017, a drastic increase in co-contamination.
  • Aflatoxin prevalence is 1% with low average contamination levels.
  • Deoxynivalenol (vomitoxin) prevalence has increased slightly to 90% vs. 85% in 2017, with average contamination level nearly doubling.
  • Fumonisin prevalence increased to 36% vs 12% in 2017, with average contamination levels increasing by 10%
  • Zearalenone prevalence jumped to 60% vs 26% in 2017, with average contamination level increasing over two fold.

These contamination levels present MEDIUM to HIGH risk for all livestock and poultry species depending on toxin and feed ingredient type. Overall, producers in the Midwest should be on the lookout for the impacts from deoxynivalenol and zearalenone, while Southern states should be vigilant regarding fumonisin and aflatoxin contamination.