Evaluation of the immune response against Pasteurella multocida

ABSTRACT

The control of pasteurellosis caused by Pasteurella multocida in rabbits remains a problem despite the vaccine available for influence subsequent rabbit reproduction performance and extent the immunity throughout the largest period. Different inactivated vaccines against pasteurellosis [Heat, Formalinized, Binary ethyleneimine [BEI] irradiated and potassium thiocyanate [KSCN] were prepared. These vaccines were tested by indirect haemagglutination test [IHT] to measure the average titers of antibodies in experimental rabbits. Data revealed that, among the tested inactivated vaccines, irradiated and KSCN gave the highest values of the overall mean of antibodies, as post-vaccination, being 1236.8 as compared to the other inactivated vaccines, followed by BEI and formalized inactivated vaccines [946.5 and 856.8, respectively when tested at 7,15,21,35,45 and 60 days. However, heat inactivated vaccine gave the lowest value, being 688.2 when estimated at the same time. Using bioassay test in rabbits, results revealed that KSCN vaccine gave the highest value, being 100% of protection against virulent strain of Pasteurella multocida. These results were followed by BEI and heat vaccine, being 90% protection, while formalinized vaccine and irradiated vaccine gave 80% protection. It was concluded that potassium thiocyanate extract vaccine is the best vaccine for protection against pasteurellosis in rabbits