Immunogenicity of vaccines made from Pasteurella multocida grown in the presence of serum

The protection induced by vaccines produced from Pasteurella multocida B: 2 (P52) grown in the presence of serum was assessed in mice model. 12 mice were immunized with these vaccines on the first day of the experiment and sera were collected on 7th, 14th, 21st, 45th and 75th day post immunization. On challenging with 104 LD50 of P. multocida (P52) on 21st and 75th day post immunization, 91% protection was conferred by serum OAV while serum concentrated low volume OAV and serum multiemulsion induced 90% and 77% protection respectively. Humoral immune response was assessed using enzyme linked immunosorbent assay (ELISA) and indirect haemagglutination assay (IHA). Our study suggests that growth of P. multocida B: 2 (P52) in the presence of serum does not have any direct effect on the protective immune response when tested in mice.