5. Conclusion
AFB1 was the main type of AF found in the dairy cow feed, with higher incidence and content than AFB2, AFG1 and AFG2. The detected levels of AFB1 were below the legal limit of 10 mg/kg in China. The detected total AF contents in the dairy cow feed samples were below the U.S. legal limit of 20 mg/kg. The low level of AFB1 in the feeds contributed to the low level of AFM1 in the raw milk. The detected AFM1 contents were lower than the legal limit in China and the U.S. of 500 ng/L. Furthermore, there was no difference observed between the north and the south in the contents of AFs in not only the dairy cow feeds and also the raw milk samples.