SERO CONVERSION STUDIES OF BRUCELLA ABORTUS SRB51 VACCINE IN CATTLE

Abstract

The sero conversion to two doses of Brucella abortus strain RB59 vaccine was assessed in cattle. Vaccinafions were done in two groups of sero negative calves of four months and above age wifh 9.8X 1010 CFU and 9 X 90i0 CFU of B. abortus strain R859 vaccine respectively by subcutaneous route. Immune responses were assessed on days 0, 7, 94, 21, 28, 60, 90, 120, 150 and180 employing indirecf ELISA. Caftle vaccinated with higher dose of B. abortus SR859 produced significant antibody level earlier (seventh day) than those with lower dose (29St day) and persisted longer (upto950 days), when compared to the group I! (only upto 920 days). Buf both groups showed maximum immune response on fhe same observation period ie., on 60th day of vaccination. The proportion of animals with significant immune responses was also higher in animals vaccinated wifh higher dose.

Keywords

• brucella abortus strain rb51
• brucella abortus sfrain 19
• sero conversion
• immune response