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 19.41 μg/kg; and 70 samples (33.3%) had levels of the toxin above the Iranian national standard and European Commission limits (5 μg/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.