Occurrence of aflatoxin B1, ochratoxin A and zearalenone in maize silage in the region of Vojvodina, Serbia

Silage made from the whole-plant maize is one of the most popular forages in Serbia. Consumption of maize silage by cows can be up to 30-35 kg/day. In Serbia in the few last years in the focus of the public and agriculture community were two mycotoxins, aflatoxin B1 and its metabolite aflatoxin M1 due to the outbreak of contaminated maize which affected the Balkans in 2012. Maize is regularly checked on the occurrence of aflatoxin B1, however forages are often neglected as a potential source of mycotoxins in the nutrition of dairy cattle.

In this work, 48 samples of maize silage were analyzed for the occurrence of aflatoxin B1, ochratoxin A and zearalenone. Samples were collected from three regions (Bačka, Banat and Srem) in Vojvodina. In all samples, at least one mycotoxin above the limit of quantification was measured. Aflatoxin B1 was detected in 36 (75%) samples. In two samples from Banat, the concentration of aflatoxin B1 exceeded the maximum level (ML) set by Serbian regulation (30 µg/kg at moisture content of 12%). In seven samples, the concentration of aflatoxin B1 was above 20 µg/kg which is the EU regulated ML. Average concentration of ochratoxin A was 10.4 µg/kg, while the maximum measured value was 34.3 µg/kg. Maximum zearalenone content in all samples was 538 µg/kg while the average zearalenone concentration was 138 µg/kg.

The results from this research point out that mycotoxin contaminated silage in the region of Vojvodina, Serbia can significantly contribute to daily intake of aflatoxin B1 in dairy cattle.