Abstract: A total of hundred exotic cattle were used during this study Based on serum agglutination test for detection of brucellosis, they were divided into two groups. Fifty Brucella positive animals were kept in group A and fifty negative in group B. All the animals were inoculated with oil adjuvant haemorrhagic septicemia vaccine. Serum samples were collected on 30, 60 and 140th days post inoculation. It was observed that geometric mean titre was 9.8 and 12.1 on 30th day 12.1 and 9.2 on 60th day in group A and B, respectively. On 140th day titres in both groups were 5.3.