Comparison of the humoral immune response against Pasteurella multocida and MannheimIa haemolytica between experimental and commercial vaccines

DÍAZ AILÉN MAGALÍ; LEDESMA MM; LEONI J; MANGHI MA; CANELLADA AM; FERRARI A; CASTRO MS

Buenos Aires

Congreso; I Meeting LASID-SAI-FAIC y LXIII Reunión Anual de SAI; 2015

SAI-FAIC

Background: Bovine Respiratory Disease (BRD) is caused by viral and bacterial agents: Pasteurella multocida (PM) and Mannheimia haemolytica (MH). Available vaccines against BRD do not always provide adequate protection against the pneumonic form of the disease affecting livestock and causing major economic problems. In this study we compared, in a murine model, the humoral immune response elicited by a commercial vaccine (CV) formulated with multiple antigens, and two experimental vaccines (EV), both composed exclusively for MH as antigen: EVH, containing aluminum hydroxide and EVF, formulated with Incomplete Freund adjuvant.Materials:Groups of mice were inoculated with 0.25 ml (s.c) of CV, EVH or EVF, and PBS as control (CG) at days 0, 15 and 27. At day 38 mice were bled and sera were separated. Specific IgG antibodies and serum avidity for MH and PM were assessed by ELISA. The antigenic recognition pattern for both bacteria was also evaluated by western blot (WB). Results: IgG levels against MH obtained with EV were higher than those with CV (p