Occurrence of aflatoxin B1 contamination in dairy cows feed in Iran

Abstract

Aflatoxins (AFs) are secondary toxic metabolites produced by fungal species. Occurrence of aflatoxin B1 (AFB1) was determined in 210 dairy cow feed samples consisting of concentrate (n=70), corn silage (n =70) and alfalfa hay ( n=70) obtained from dairy farms in central part of Iran during July-September 2014. AFB1 analysis was carried out by using the competitive enzyme-linked immunosorbent assay technique for screening and high performance liquid chromatography for confirmatory purpose. AFB1 was detected in 88 analyzed samples (41.9%), ranging from 1.87 to 19.41g/kg; and 70 samples (33.3%) had levels of the toxin above the Iranian national standard and European Commission limits (5g/kg). The frequencies of AFB1 contamination in the samples were as follows: alfalfa hay, 55.7%; concentrate, 44.3% and corn silage, 25.7%. The high occurrence of AFB1 contamination may be attributed to poor harvesting technique, environmental conditions, insect infestation or unsuitable storage conditions. Hence, the contamination with AFs could be a potential hazard for human and animal health.