Validation of immunity induced by inactivated CCPP vaccine with different adjuvants

摘要

The study was conducted in the premises National Veterinary Institute (NVI) to validate the immunity induced by inactivated F38 antigen adjuvated with saponin and Montanide ISA 50 and combined with and without anthrax vaccine. Post-inoculation reactions; pyrogenic effects, safety and inocuity of the vaccines were assessed. Increased body temperature and local edematous reactions were seen in animals inoculated with saponin adjuvated CCPP vaccine (100%) while 20% of the goats in ISA 50 adjuvated group showed local reaction. Sera collected from day 0 to 10th week were tested to assess the sero-conversion using monoclonal antibody based B-ELISA technique. Saponin adjuvated groups, in both monovalent CCPP and in the combined CCPP with anthrax vaccine showed a higher mean percentage of inhibition value as compared with ISA 50 adjuvated vaccine. After 8 months of post vaccination, contact challenge trial was conducted in 66 experimentally vaccinated and 20 negative control goats combined with 15 actively CCPP sick goats. Various clinical signs were recorded daily, autopsy was done on died goats and the live goats were sacrificed after 2 months of contact. The side by side samples from thoracic exudates, lung and mediastinal and bronchial lymph nodes were collected from goats shown to have developed indicative CCPP lesion for isolation and F38 antigen detection. The present experimental study indicated that application of inactivated and adjuvated CCPP vaccine significantly reduced the morbidity and development of lesions (P < 0.001). Among vaccinated groups CCPP + anthrax + saponin showed better protection, with low rate of nasal discharge and cough at 33% and 28.6%, respectively, and protection level of 94.1% from death and 65% from lung lesion development. However, the variation in protection among the vaccinated groups was not significant (P > 0.05). These findings disclosed that inactivated CCPP vaccine adjuvated with saponin and ISA 50 significantly reduce morbidity and mortality of goats due to CCPP and also indicated the importance of utilization of ISA 50 as alternative adjuvant to minimize post-vaccinal reactions encountered in use of saponin as adjuvant.