Adsorbents Reduce Aflatoxin M1 Residue in Milk of Healthy Dairy Cow Exposed to Moderate Level Aflatoxin B1 in Diet and Its Exposure Risk for Humans

This study investigated the effect of moderate risk level (8 mu g/kg) AFB(1) in diet supplemented with or without adsorbents on lactation performance, serum parameters, milk AFM(1) content of healthy lactating cows and the AFM(1) residue exposure risk in different human age groups. Forty late healthy lactating Holstein cows (270 +/- 22 d in milk; daily milk yield 21 +/- 3.1 kg/d) were randomly assigned to four treatments: control diet without AFB(1) and adsorbents (CON), CON with 8 mu g/kg AFB(1) (dry matter basis, AF), AF + 15 g/d adsorbent 1 (AD1), AF + 15 g/d adsorbent 2 (AD2). The experiment lasted for 19 days, including an AFB(1)-challenge phase (day 1 to 14) and an AFB(1)-withdraw phase (day 15 to 19). Results showed that both AFB(1) and adsorbents treatments had no significant effects on the DMI, milk yield, 3.5% FCM yield, milk components and serum parameters. Compared with the AF, AD1 and AD2 had significantly lower milk AFM(1) concentrations (93 ng/L vs. 46 ng/L vs. 51 ng/L) and transfer rates of dietary AFB(1) into milk AFM(1) (1.16% vs. 0.57% vs. 0.63%) (p < 0.05). Children aged 2-4 years old had the highest exposure risk to AFM(1) in milk in AF, with an EDI of 1.02 ng/kg bw/day and a HI of 5.11 (HI > 1 indicates a potential risk for liver cancer). Both AD1 and AD2 had obviously reductions in EDI and HI for all population groups, whereas, the EDI (>= 0.25 ng/kg bw/day) and HI (>= 1.23) of children aged 2-11 years old were still higher than the suggested tolerable daily intake (TDI) of 0.20 ng/kg bw/day and 1.00 (HI). In conclusion, moderate risk level AFB(1) in the diet of healthy lactating cows could cause a public health hazard and adding adsorbents in the dairy diet is an effective measure to remit AFM(1) residue in milk and its exposure risk for humans.