DETERMINATION OF AFLATOXIN IN DAIRY FEEDS AND MILK IN SOME SELECTED AREAS OF ETHIOPIA

Abstract

Aflatoxin B1 (AFB1) in feeds and aflatoxin M1 (AFM1) in milk were studied in Holetta, Bishoftu and Hawassa, Ethiopia using Enzyme-linked Immunosorbent Assay (ELISA). Concentrate feeds  were more contaminated (7.67 ± 0.80 μg/kg) than roughage feeds (0.41 ± 0.14 μg/kg); hay was more contaminated (0.72 ± 0.25 μg/kg) than straw (0.05 ± 0.05 μg/kg) and oilseed cake based concentrate feeds were more contaminated (13.09  ± 1.12 μg/kg) than concentrate feeds without oilseed cake (2.78  ± 0.66 μg/kg). Fifty percent of the feed samples contained 0 µg/kg aflatoxin and 69% and 31% of them fulfilled the permissible limit of the EU (5μg/kg) and the USA (20 μg/kg) for feeds respectively. The average AFB1 of feeds in Bishoftu, Holetta and Hawassa were 9.76µg/kg, 6.33µg/kg and 1.19µg/kg, respectively. The AFB1 of feeds in dairy producers, feed manufacturers and feed retailers were 9.35 ± 1.04µg/kg, 7.50 ± 1.43 µg/kg and 6.91 ± 1.09µg/kg respectively. Twenty nine percent of the milk samples had aflatoxin content of 0 μg/L and; 58% and 42% of them fullfilled the EU (0.05μg/L) and the U.S.A.(0.5 μg/L) permissible limits respectively. Further studies are required by using other techniques such as HPLC, GC and multi-mycotoxin assay using LC-MS-MS. The contribution of too acidic and too alkaline PH on aflaoxin reduction should also be studied. Awareness creation is required to feed processers, feed traders and dairy producers along the feed-milk production and marketing chain. To minimize the incidence of aflatoxin, feed processers, feed traders and dairy producers should employ better feed/grain storage practices.