Efficacy of various levels of mycotoxin adsorbent to reduce aflatoxin M1 levels in milk of lactation cows fed aflatoxin B1
The aim of this study was to compare the ability of various levels of adsorbent Biotox (Biochem GmbH, Lohne, Germany) to reduce Aflatoxin in milk of Holstein cows. Twenty four lactating Holstein cows in mid lactation were assigned to 1 of 3 treatments (n=8) for 35 days. Diet formulated according to the nutrient requirements of dairy cattle (NRC, 2001). The following treatments were investigated 1- Aflatoxin diet plus 60 g/day/cow of Biotox (Biochem GmbH, Lohne,. Germany), 2- Aflatoxin diet plus 20 g/day/cow of Biotox and 3- Aflatoxin diet without mycotoxin adsorbent (Control). Aflatoxin diet provided 350 μg/day/cow of AFB. Individual dry matter intake and milk yield were recorded daily. Milk samples were collected at each milking time weekly. Blood samples (10 ml) were collected weekly from the coccygeal vein and centrifuged to separate plasma. Quantification of aflatoxin (B1 or M1) in TMR samples, Milk and plasma done using microtitre plate enzyme linked immunosorbent assay (ELISA) method. Weekly data were analyzed using the MIXED procedure of SAS as repeated measurement data. Aflatoxin M1 concentrations for the Biotox60, Biotox20 and control (no adsorbent) treatments averaged 338.0, 439.0 and 490.1 ng/kg, respectively. Compared to the control group, AFM1 concentrations in milk were reduced (P = 0.015) by the addition of 20 and 60 g/day/cow of Biotox. Aflatoxin M1 excretion via milk, as calculated from milk AFM1 concentration and total milk volume produced, was 9.87, 12.87 and 14.66μg/d/cow in the Biotox60, biotox20 and control treatments respectively. Biotox significantly decreased AFMI excretion in milk (p=0.033). Transfer rate of AF from feed to milk (TR), as calculated from [(excretion of AFM1/AFB1 consumption) × 100] averaged 2.90, 3.85 and 4.22 % for the Biotox60, biotox20 and control treatments respectively. Biotox in 60 g/day dose significantly decreased Aflatoxin TR (p=0.029). The results of the analysis of variance on plasma AFM1showed that treatment did not affect plasma AFM1but numerical increase in plasma AFM1 of control group showed. Results of the current study indicate that the Biotox was effective in reducing milk AFM1 concentrations, AF excretion, and AF transfer from feed to milk, but this efficacy was improved in higher dosage (60g/day/cow) at least in high polluted diets.
Keywords: Aflatoxin, transfer rate, milk