Introduction
Mycotoxins are secondary fungal metabolites which are frequently found in various plant-based ingredients and can negatively affect health and performance of aquatic species. The increasing inclusion of plant protein in aqua feed, leads to the introduction of mycotoxins in aqua diets. Mycotoxin occurrence in raw ingredients as well as finished feed is monitored within the DSM Mycotoxin Survey, the longest running global mycotoxin survey available. Global results between January-June 2023 of prevalence and concentrations of the six well known mycotoxins aflatoxins (Afla), zearalenone (ZEN), deoxynivalenol (DON), T-2 toxin (T-2), fumonisins (FUM) and ochratoxin A (OTA), in commonly used ingredients are presented.
Material and methods
Samples were analyzed with ELISA, HPLC and LC-MS/MS (liquid chromatography coupled to tandem mass spectrometry) based methods. For Asia, mainly the multi-mycotoxin method Spectrum Top®50 developed by Romer Labs®, was used. This method allows the simultaneous detection of >50 different toxins and metabolites, including masked and “emerging” (unregulated) mycotoxins.
Results and discussion
Table 1 shows the number of samples analyzed, % of samples tested positive for each mycotoxin, average concentration of all positive samples (ppb), median concentration of all positive samples (ppb) as well as the maximum (ppb) detected.
Afla occurs most frequently in soybean, but at moderate levels. Wheat/-bran shows high abundance of DON. Corn is frequently contaminated with Fusarium toxins (ZEN, DON, FUM), but shows also an extreme Afla maximum. Corn gluten meal and corn DDGS are risky ingredients due to high contamination. Poster will also provide details on rice bran, cottonseed - and sunflower cake, rapeseed meal as well as cassava.
Conclusion
Prevalence and concentrations of the six well known mycotoxins underline the importance of a proper mycotoxin risk management including regular testing of ingredients as well as testing of aqua finished feed and inclusion of a mycotoxin deactivator.