Mycotoxin Survey in US corn: March 2019 update

Corn

  • 98% of ground corn samples were positive for at least one mycotoxin, vs 89% in 2017
  • 73% of samples had more than one mycotoxin, vs 47% in 2017
  • Aflatoxin prevalence in dry corn jumped to 9% vs 4% in 2017, with average contamination levels increasing nearly five-fold.
  • Deoxynivalenol (vomitoxin) prevalence was 76% vs 70% in 2017, with average contamination level increasing by 38%
  • Fumonisin prevalence has increased to 79% vs 52% in 2017, with average contamination levels increasing by 49%
  • Zearalenone prevalence has jumped to 45% vs 25% in 2017, with average contamination levels remaining steady.

Corn By-Product

  • 95% of samples were positive for at least one mycotoxin, vs 100% in 2017
  • 90% of samples had more than one mycotoxin, vs 94% in 2017
  • Aflatoxin prevalence is 2% vs. 9% in 2017, both years with similar and low contamination levels.
  • Deoxynivalenol (vomitoxin) prevalence is 93% vs 99% in 2017, with average contamination level increasing by 34%
  • Fumonisin prevalence is 88% vs 91% in 2017, with average contamination levels decreasing by 20%
  • Zearalenone prevalence is 85% vs 80% in 2017, with average contamination level increasing over two fold.

Corn Silage

  • 89% of samples were positive for at least one mycotoxin, vs 91% in 2017, a drop of nine percentage points from our February report.
  • 62% of samples had 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 remained steady at 85%, with average contamination level increasing by 80%
  • Fumonisin prevalence was 28% vs 12% in 2017, with average contamination levels increasing by 25%
  • Zearalenone prevalence was 58% vs 26% in 2017, with average contamination level doubling.

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.