Serological evidence of Brucella abortus prevalence in Punjab province, Pakistan--a cross-sectional study.

Twenty-one villages in Punjab Province, seven from each region (North, Central& South) were randomly selected to determine the prevalence of B. abortus infection by two age categories (Group A: 0–2 years; Group B: >2 years) in cattle and buffalo populations. In each village, eight blood samples were collected from each age group of cattle and buffaloes. Sera from a total of 672 blood samples (336 each from cattle and buffaloes) were analysed for the presence of antibodies to B. abortus using rose bengal plate agglutination test (RBPT). Further confirmation of the RBPT-positive samples was carried out using competitive ELISA. Overall, 43 of 672 (6.4%) sera were found positive for the presence of antibodies to B. abortus using RBPT. In cattle, the prevalence of B. abortus antibody was 5.06%, and in buffaloes, it was 7.74%. From the RBPT-positive sera, 30 (70%) sera were confirmed for B. abortus antibodies using competitive ELISA. Results indicated that the prevalence of infection increased with the age of animals i.e. 3.27% and 9.52% in groups A and B, respectively. In cattle, incidence of these antibodies was 3.57% and 6.54% while in buffaloes, it was 2.98% and 12.50% in groups A and B, respectively. The region-wise prevalence of B. abortus infection in buffaloes was 3.13%, 4.46% and 4.02% and in cattle, it was 3.13%, 1.79% and 2.68% in Northern, Central and Southern regions, respectively. This study provided baseline data on the occurrence of brucellosis infection in cattle and buffaloes at village level. This is the first study in Punjab province on the prevalence of brucellosis at village level.