Trends in Mycotoxin Contamination of the 2022 United States Corn Crop

Abstract Mycotoxins are harmful secondary fungal metabolites detrimental to animal health, even at reduced quantities. Focus on clinical signs such as decreased feed intake and vomiting overlook impacts of mycotoxicosis, including increased disease incidence and severity, immune modulation, inflammation, and gastrointestinal disorders. This study was conducted to compare mycotoxin contamination of initial samples of the 2022 corn crop with previous year trends. Samples were analyzed utilizing the liquid chromatography with tandem mass spectrometry (LC-MS/MS) method for six major mycotoxin groups: aflatoxins (Afla), type A trichothecenes (A-Trich), type B trichothecenes (B-Trich), fumonisins (FUM), zearalenone (ZEN), and ochratoxin A (OTA). The 2022 crop year data were compared with the prior four harvest years using GLIMMIX procedure of SAS with harvest year as fixed effect and sample as the experimental unit. A limited number of samples is available thus far (n = 44) as harvest is still progressing, therefore the risk profile of this crop year is likely to change as the sample pool expands. Contamination levels in corn for the tested toxin groups have remained consistent over the survey period. To date, 97% of the samples evaluated contained at least one mycotoxin, compared with 90% that was observed in 2021. The percentage of Afla contaminated samples increased (P < 0.05) in 2022 corn compared with the 2020 and 2021 harvest years (42 vs. 5 and 7%). The percentage of FUM contaminated samples in 2022 corn is greater (P < 0.05) compared with 2020 and 2021 (88 vs. 64 and 64%). The preliminary results of the 2022 US corn crop survey indicate mycotoxin occurrence and contamination levels are similar or greater (Afla and FUM) to the prior crop year and will continue to challenge animal health and performance as these ingredients are fed out.