Excretion pattern of aflatoxin M1 in milk of goats fed a single dose of aflatoxin B1

Abstract

The feedstuffs used in dairy animals must be able to give consumers confidence about the wholesomeness of milk with regard to aflatoxin contamination. The aim of this study was to determine the excretion patterns of aflatoxin M1 (AFM1) in the milk of dairy goats fed a single dose of pure aflatoxin B1 (AFB1), which can occasionally occur if feeds are infected by hot-spot growth of molds that produce aflatoxins. Five dairy goats in midlactation were administered 0.8mg of AFB1 orally. Individual milk samples were collected for 84h after AFB1 dosage. Aflatoxin M1 was found in milk in the highest concentration. In all goats, AFM1 was not detected in milk before AFB1 administration, but was detected in the first milking following AFB1 administration. The excretion pattern of AFM1 concentration in milk was very similar in all goats even if the values of the concentration differed between animals. The peak values for AFM1 concentration in milk was observed in milk collected during the milking at 3 and 6h. After the peak, the AFM1 in milk disappeared with a trend that fitted well a monoexponential decreasing function, and the toxin was not detected after 84h. Only about 0.17% of the amount of AFB1 administered was detected as AFM1 in milk, and about 50% of this was excreted in the first liter of milk yielded after AFB1 intake. Correct procedures to prevent growth of molds, and consequent AFB1 contamination, on the feedstuffs for lactating goats represent the key to providing consumers a guarantee that milk is not contaminated by AFM1.