Occurrence and transfer of mycotoxins from ingredients to fish feed and fish meat of common carp (Cyprinus carpio) in Serbia

Abstract

As fish has been known for its high protein content and other health benefits, aquaculture production has started to flourish in Serbia. Common carp is the predominant species being farmed, comprising more than 80% of the total fish production in Serbia. The primary ingredients in fish feed are plant-based products, which present a risk of mycotoxin contamination, posing a potential risk to consumers. Therefore, this study aimed to determine the mycotoxin status of carp aquaculture in Serbia. At the beginning of the feeding season, May to June 2019, 27 samples of feed ingredients, 8 of finished feed and 14 of edible fish meat were analysed. The fish feed and feed ingredients were sampled from local producers, while the fish were sampled from fish farms that were reported to use the sampled feed. The feed ingredients were locally produced maize and maize products, sunflower meal, soybean and soybean products, wheat, bone meal, yeast and distillers dried grains with solubles, which were ground together, mixed and pelleted in different sizes. All samples were tested for the presence of aflatoxins (aflatoxin B1 (AFB1), B2, G1 and G2), ochratoxin A (OTA), zearalenone, deoxynivalenol, fumonisins (fumonisin B1 and B2), HT-2 and T-2 toxins. The most prevalent mycotoxins were OTA (91.4%), fumonisin B1+B2 (68.6%) and AFB1 (48.6%). Only one sample of the plant-based ingredients was below limit of quantification (LOQ), and more than 85% of the samples had more than one mycotoxin detected, ranging from 0.43 μg/kg of AFB1 to 3,168.5 μg/kg of fumonisin B1+B2. However, all the samples of edible fish meat were under the LOQ. We suggest that further research should be conducted on the effects of co-occurring mycotoxins; we also recommend stricter regulations on fish feed to reduce the impacts of mycotoxins on fish health and productivity.