Corn silage as a source of aflatoxin B1 in feed for dairy cattle

Nutrition of dairy cattle is based on two components, concentrates and forages. The main forages in Vojvodina, north province of Serbia is silage made from the whole plant of corn. After the outbreak of aflatoxin B1 in corn in 2012, the occurrence of aflatoxin B1 in corn as a source of contamination of aflatoxin M1 in milk was very broadly investigated. There is no data regarding the occurrence of aflatoxin B1 in silage and how much silage can contribute to the overall intake of aflatoxin B1 in this region. This work is an attempt to estimate how much silage, in condition and practice used in Vojvodina, contributes to the intake of aflatoxin B1, and consequently aflatoxin M1 in milk. In total, 82 samples of corn grain and 72 samples of corn silage were analyzed on the occurrence of aflatoxin B1 during 2017-2018 period. Aflatoxin B1 was found in 13.41% of corn samples in the range from 6.82 to 187.5 ppb (average 63.5 ppb). All positive samples were from 2017, while no positive samples were found during 2018. Incidence of aflatoxin B1 in silage was 54.17% in the range of 3.5-58.0 ppb (12% moisture content) or 0.95-16.1 ppb in the fresh matter. Results suggest that silage can be a significant factor to overall intake of aflatoxin B1 and that further research is needed.