Impact of Maternal Antibody and Concurrent Vaccination on Serologic Responses to Clostridial Vaccination in Calves

At birth, one hundred and fifty beef calves were randomly assigned to one of three groups. Dams of the calves had received no vaccines for at least two years. At day sixty of age, serum was drawn for antibodies against exotoxins from Clostridium perfringens (Clp) type C and D, Cl. novyi (Cln) and Cl. sordellii (Cls). Calves in group one were administered 2ml of an intranasal vaccine containing modified live BHV-1, BRSV and PI3 virusa (IN), a modified live viral vaccine containing bovine viral diarrhea virus (BVDV) types 1 and 2 in combination with a Mannheimia hemolytica (BVDMh) inactivated leukotoxoidc and a Clostridium Chauvoei-Septicum-Novyi-Sordellii-Perfringens Types C and D Bacterin-Toxoid vaccine (7way).b Calves in group two received a systemic MLV combination vaccine containing BVDV types 1 and 2, BHV-1, BRSV, PI3 virus and the same Mh vaccined (FivewayMH). Group three were vaccinated with only the 7 way Clostridium vaccine. At 210 days of age serum was drawn and calves in group 1 received the FivewayMH and 7way vaccines. Calves in group 2 were administered the IN, BVDMH and 7way vaccines and group 3 calves were vaccinated with only the 7way. At 240 days of age sera was drawn for final SN titers. At 60 days of age high levels of maternal antibody against all the exotoxins tested were detected. Serologic responses in all groups indicated maternal antibody interference after 7way vaccination to Cl. Perfringens C and D and in group 3 to Cl. novyi and sordellii. Interference of the immune response to Cl. novyi by systemic MLV BHV-1 viral vaccination was seen on day 60 and 210 to Cl. sordellii. This study indicates that both maternal antibody and concurrent systemic BHV-1 vaccination may interfere with serologic responses to Clostridial exotoxin vaccination. The impact of the decreased antibody levels on protection could not be determined in this study.