338 A Survey of Mycotoxin Occurrence in Us Corn and Corn By-Product Feed Ingredients from 2018 to 2022 Harvest Years

Abstract

Abstract The aim of this survey was to compare the occurrence and contamination levels of six major mycotoxin categories found in corn and corn by-product feed ingredients harvested in the United States from 2018 through 2022. Mycotoxins are secondary fungal metabolites that can negatively impact animal health and performance and have been routinely found in a variety of feedstuffs including, but not limited to, cereal grains, by-products, silages, dry hays and pasture grasses. Mycotoxin categories evaluated in this survey included: aflatoxins (AFLA), type A trichothecenes (A-Trich), type B trichothecenes (B-Trich), fumonisins (FUM), zearalenone (ZEN), and ochratoxin A (OTA). This study includes data from corn samples labeled as 2022 harvest and corn b-product feed ingredients submitted from October 2022 through March 2023 and were analyzed for 17 different metabolites via the Liquid Chromatography with tandem mass spectrometry (LC-MS/MS) method. Samples that tested above the limit of detection for each mycotoxin group were analyzed using the generalized linear mixed model procedure of SAS (SAS 9.4, Cary, NC) using harvest year as a fixed effect. The effect of harvest year on average contamination level for each mycotoxin is presented in Table 1. For 2022 harvest year, 260 corn samples and 66 corn by-product samples have been evaluated to date. Mean B-Trich, ZEN, FUM and AFLA levels (parts per billion, ppb) for corn grain samples were similar in 2022 as previous years (P > 0.05). However, for corn grain samples, FUM prevalence and concentration were numerically greater in 2022 than in 2021 and 2020. In the 66 samples of corn by-products, FUM was found in all the samples (100%) and B-Trich were found in the majority of the samples (97%). Mean concentration of FUM in 2022 corn by-product samples was greater (P < 0.001) compared with 2021. Preliminary results of this survey suggest mycotoxin occurrence and contamination remains similar to previous harvest years except for greater mean FUM concentration levels in corn and corn by-products feed ingredients.