Assessment of aflatoxin B1 contamination level in dairy animal feeds from selected towns of North Shoa Zone, Oromia, Ethiopia

Aflatoxins are secondary metabolites produced by certain Aspergillus fungi in foods and feedstuffs due to poor storage and favorable climatic conditions suitable for fungal growth. Among the most common types of aflatoxins, aflatoxin B1 (AFB1) is highly toxic and causes acute or chronic toxic effects to both humans and animals. This study, therefore, was conducted to determine the levels of AFB1 in dairy cow feed samples collected from Fiche and Degam towns of North Shoa Zone. A total of 50 feed samples, comprising 41 composited and 9 individual of each composited, were collected randomly from smallholder dairy farmers, and the levels of AFB1 were determined via High-Performance Liquid Chromatography coupled with Fluorescence Detector (HPLC-FLD) after being cleaned with immune affinity columns. The highest AFB1 content found in composited feed samples was 30.8 µg/kg, while the lowest was 0.0100 µg/kg. Out of 41 analyzed composite feed samples, 35 (85.4%) samples had levels above the detection limit of AFB1, out of which 16 (39.0%) contained AFB1 that exceeded the European Commission maximum permissible level (5 µg/kg) for dairy feed samples. Six samples (14.6%) were found to be below the limit of detection. Thus, different concentrations of AFB1 were detected in dairy feed samples collected from two towns within the North Shoa Zone, exhibiting considerable levels of contamination. Therefore, the finding of this study highlights the importance of rigorous regulatory monitoring and improved feed handling techniques to safeguard consumers of animal-derived products from the serious health consequences linked to aflatoxins.