Bovine immune colostral antibocly against verotoxin 2 derived.from Escherichia coli O157:H7- Resistance to proteases and effects on verotoxin 2 in small intestine ojCheagle dogs

Resistance to intestinal proteases and efficacy against verotoxin (VT) 2 of a colostral antibody administered orally via catheter were investigated in beagle dogs. Bovine colostral antibody remained in the small intestine for 2 hours, whereas little serum antibody remained at 1.5 hours after administration. The bovine colostral antibody was not inactivated by proteases in the small intestine. Furthermore, the antibody activity of S-IgA did not change until 2 hours after administration; however, the activity of IgG and IgM antibodies decreased by two-thirds and two-fifths at 2 hours after administration, respectively. Seven beagle dogs inoculated with lischerichia coli (E coli) O157:H7 producing VT2 were administered bovine colostral antibody or bovine colostral whey without antibody. With administration of bovine colostral whey without antibody, the amount of VT2 in feces decreased gradually after administration and increased again at 5 days after inoculation, while bovine colostral antibody significantly reduced the amount of VT2 in feces the day after administration. In addition, 9 beagle dogs were administered bovine colostral antibody, bovine plasma antibody or sali.ne. The amount of VT2 in feces also significantly reduced rapidly after administration ofboyine colostral antibody than administration ofbovine plasma antibody or saline.