0115 Occurrence of mycotoxins in the 2015 U.S. corn crop

Mycotoxins are toxic metabolites produced by filamentous fungi which commonly contaminate feedstuffs harvested for both human and livestock consumption. Although the different types of mycotoxins have variable effects on different livestock species, exposure to mycotoxins can impair health and adversely affect animal performance. The objective of the current study was to determine the occurrence of mycotoxins in the 2015 corn crop in the United States and to assess the potential risk to livestock species. From September 2015 to January 2016, 381 corn samples were collected from 20 states as part of the annual Biomin Mycotoxin Survey. Samples were analyzed either by high performance liquid chromatography (HPLC) or liquid chromatography tandem mass spectrometry (LC-MS/MS) techniques, which are highly sensitive in detecting very low mycotoxin concentrations. The major mycotoxin groups analyzed were aflatoxins (Afla), zearalenone (ZEN), trichothecenes including deoxynivalenol (DON) and T-2 toxin (T-2), fumonisins (FUM), and ochratoxin A (OTA). Mycotoxins were detected in 94% of the corn samples tested and 50% of the positive samples contained more than one mycotoxin. Co-occurrence of mycotoxins may lead to synergism and enhanced toxicity in animals which consume contaminated feed. The percentage of positive samples, mean of positives (ppb), maximum of positives (ppb), and risk threshold (ppb) for the six major mycotoxins are presented in Table 1 (not available). The occurrence of Afla, T-2, and OTA were minimal in relation to ZEN, DON, and FUM in these samples. The highest threat in these corn samples was posed by DON due to its high prevalence and number of samples above the FDA recommended level. As a result of their common co-occurrence, ZEN also presents a major threat. In terms of occurrence, FUM ranks second among the six major mycotoxins analyzed in these samples. With the increased occurrence and co-occurrence levels in 2015 compared with the previous year, DON, FUM, and ZEN pose a higher risk to livestock production in 2016.