PREPARATION AND COMPARATIVE EVALUATION OF HAEMORRHAGIC SEPTICAEMIA VACCINES USING EOLANE-150 AND EOLANE-170 AS OIL ADJUVANTS FOR CATTLE AND BUFFALO : Veterinary Research Institute, Lahore Cantt, Pakistan

Haemorrhagic septicaemia (HS) caused by Pasteurella multocida serotype B:2 is an economically important disease of cattle and buffalo, causes heavy economic losses due to sudden death of animals in developing countries like Pakistan. In this country, animals are vaccinated by alum (adjuvant) precipitated vaccine twice a year. Immunity induced through this prophylactic measure lasts for 3-4 months only. Two new HS oil based vaccines were prepared by using two new oil adjuvants such as Eolane-150 and Eolane-170. The ratio of bacterial antigen and oil adjuvants was 1:1 while bacterial dry weight was adjusted to 2 mg/ml. The addition of enrichments and aeration resulted in dense bacterial growth of Pasteurella multocida. Both new vaccines passed sterility, safety and potency tests as per OIE, 2017. Active and passive Mouse Protection Tests were performed to evaluate its potency. Indirect Haem-Agglutination (IHA) test was conducted on serum samples of two rabbits, groups each of which was vaccinated with HS oil based vaccines adjuvanted with Eolane-150 and Eolane-170. IHA indicated that immune response was higher (GMT=32) initially on 45th day to 75th day post vaccination and then declined (GMT=16) in the rabbits vaccinated with HS vaccine adjuvanted with Eolane-150, while protective immune response remained constant (GMT=16) up to ninety days post vaccination in the rabbits vaccinated with HS vaccine adjuvanted with Eolane-170. Vaccines were easy to inject with no side effects, including swelling at the injection site and longer protection as well. That would hopefully motivate the livestock owners and farmers to use this new product to protect their animals against this fatal HS disease.