Mycotoxin Prevalence in the 2017 Corn Crop

Mycotoxins are harmful secondary fungal metabolites, and are of key concern to food and feed safety globally. In addition to compromised performance, mycotoxins negatively impact animal health. Although classic symptoms such as decreased feed intake and vomiting are utilized in the field as an indicator for exposure, even at low levels mycotoxins act as predisposing factors for diseases by immune suppression, causing inflammation, and modulating the gastrointestinal environment. This survey presents information regarding mycotoxin contamination of samples from the 2017 corn harvest compared to the prior two years. New crop corn samples from feed mills, integrators and producers were submitted from mid-August to December 2017. All participants were informed of best sampling practices. Samples were analyzed utilizing the LC-MS/MS method for six major mycotoxin groups: aflatoxins, type A trichothecenes, type B trichothecenes (B-Trich), fumonisins (FUM), zearalenone (ZEN) and ochratoxin-A. Data is presented for Fusarium mycotoxins in table 1. A majority of samples contained at least one detected mycotoxin; however, co-occurrence (≥2 mycotoxins) in samples thus far is lower than 2016. Prevalence of ZEN and FUM are less this year compared to 2017, but B-Trich prevalence is similar to last year. Although contamination levels for DON have decreased, levels are still higher compared to the 2015 harvest while FUM levels are comparable to the 2016 crop and numerically higher than the 2015 crop. The preliminary results from the 2017 corn harvest suggest a continued risk from mycotoxins produced by Fusarium fungal species. Because of the risk of multi-mycotoxin contamination in samples thus far, multiple mitigation strategies are needed beyond adsorption, including biotransformation and supporting the immune system and liver function.

Table 1. Fusarium toxin contamination by year
	Year
Parameter	2015		2016		2017
N	318		595		252
Toxin Count	1.4a		2b		1.6a
B-Trich
Prevalence (%)	72a		85b		77ab
Median (ppb)	400		933		557
Average (ppb)±SEM	691a±204		1845b±137		1325c±221
> 1000 ppb (%)	13		41		21
ZEN
Prevalence (%)	17a		51b		30c
Median (ppb)	107		183		130
Average (ppb)±SEM	247±138		356±57		325±117
> 1000 ppb (%)	5		24		12
FUM
Prevalence (%)	52a		61b		46a
Median (ppb)	500		1400		800
Average (ppb)±SEM	1190a±542		3998b±361		2746ab±644
> 1000 ppb (%)	15		36		20

a-c Means are statistically significant different p < 0.05