1Division of Bacteriology and Mycology, IVRI, Izatnagar, Bareilly, UP-243122.
Department of Microbiology and Immunology, College of Veterinary Science and Animal Husbandry, Pandit Deen Dayal Upadhyay Veterinary and Animal Science University, Mathura – 281001, Uttar Pradesh, India.
Haemorrhagic septicaemia (HS) caused by Pasteurella multocida (P. multocida) B:2 is an important fatal disease of cattle and buffaloes occurring as catastrophic epizootics in many Asian and African countries resulting in high mortality. Present study was carried out to use of outer membrane proteins (OMP) as vaccine candidate to improve the HS vaccine and its comparison with APV and OAV in mice model. The SDS-PAGE profile of OMP showed four major (25.6, 28, 37 and 84.5 kDa) and five minor (27, 44, 56, 66.8 and 88 kDa). Immunoblotting revealed 3 major (27, 44 and 66.8 kDa) and 2 minor (37 and 56 kDa) immunogenic proteins. Humoral immune response was studied by indirect ELISA at various time periods post-vaccination. Vaccine efficacy trials were conducted in mice through s.c. route. It was found that on 35th day post vaccination antibody titre was lower in case of OMP oil adjuvant vaccine (9600) than OAV (25600), but was similar to that of APV (9600). The mice were challenge on 35th day post-vaccination with 10LD50 i.e. 0.2 ml of 10−4 dilution of 18 hrs broth culture of P. multocida per mouse i.p. Highest protection level was recorded in mice vaccinated with OAV (83.3%). 66.7% protection was observed in mice immunized by either of OMP oil adjuvant vaccine or APV. This present study showed that OMP was the immunogenic component of the P. multocida and able to induce satisfactory protective antibody in animals as evidenced by challenge test.
