Study on Immunity of an Experimental Oil Adjuvant Haemorrhagic Septicaemia Vaccine in Cattle.

An oil adjuvant vaccine (OAV) was prepared from a local strain of Pasteurella multocida. Strain 6:B was cultured and inactivated by formalin. Bacterial pellet was prepared by centrifugation and subsequently adjuvanted by Montannide oil ISA-70. A dose of prepared vaccine containing 3ml (2mg dry weight/ml) was injected into five calves by IM route. Animals were bled before and at 24, 90, 150, and 200 days post-vaccination. Collected sera were used in passive mouse protection test (PMPT). Active mouse protection test (AMPT) was carried out for OAV according to standard method. Results of PMPT showed 100% protection up to 150 days and 66-83% up to 200 days post-vaccination. In AMPT, 4 log of protection was gained. In this experiment the immunity induced by OAV adjuvanted by ISA-70 could protect the calves.