Reduction of Milk Contamination with Aflatoxin-M1 through Vaccination of Dairy Cattle with Aflatoxin-B1 Vaccine

Abstract

Aflatoxin M1 is one of mycotoxin derivatives, which is secreted in milk of dairy cattle fed on feed contaminated with Aflatoxin-B1 (AFB1). The current study was designed to prepare a vaccine against AFB1and to evaluate its efficacy in reducing or preventing secretion of AFM1 in milk. Aflatoxin-B1 was prepared, purified and transformed into oxime, then it was fixed on bovine serum albumins. The AFB1-BSA conjugate was adjuvanted with Gold Nano particles then Montanide ISA 206. The prepared vaccine was used for immunization of rabbits by S/c routes as 100 µg/dose and dairy cattle by I/M routes as 500 µg/dose. The vaccinated animals were boosted at 3 weeks post primary immunization. Serum samples were collected and examined for the anti-AFB1 using AGPT. A mean titer of 15.2 AGPU/ml was detected at 2 weeks post primary vaccination then significantly increased till reached to 76.8 AGPU/ml at 6 weeks post Booster vaccination. All vaccinated rabbits were challenged with dose of 0.3 mg AFB1 toxin/Kg. The vaccinated rabbit showed 100% protection and no AFB1 toxin residue was detected in their livers. Milk samples were collected from non-vaccinated and AFB1-immunized dairy cattle then examined with ELISA for quantitation of AFM1 residues before and after vaccination. The results showed that the prepared AFB1 vaccine was safe, potent and able to reduce AFM1 release in milk of vaccinated heifers by 70%. So the vaccination of lactating animals with the AFB1vaccine might represent a valid tool for the prevention of AFM1 contamination of milk and dairy products.