MOLECULAR AND SEROLOGICAL DETECTION OF BRUCELLA MELITENSIS IN CAPRINE POPULATIONS: BANGLADESH AGRICULTURAL UNIVERSITY GOAT FARM

Background: Brucellosis is one of the most important zoonotic diseases affecting a range of animals caused by Brucella species. Reported to have zoonotic importance include B. abortus, B. melitensis, B. suis, and B. canis. The causative agents of brucellosis in small ruminants are B. abortus, B. melitensis, and B. ovis, mainly associated with abortion, stillbirth, placentitis, and weak offspring, with the development of yellowish, sticky layers on the placenta in females, while in males, orchitis, epididymitis, as well as inflammation of the joints and bursae, are affected. Most serological studies have reported a high prevalence of caprine brucellosis in Bangladesh. However, molecular and serological detection of B. melitensis in caprine populations involves using a combination of antibody tests and DNA-based methods to identify infection. Objective: The main aim of this study was to confirm RBPT- and ELISA-positive cases of B. melitensis infection in goats at BAUGF using a combination of serological (RBPT, i-ELISA) and molecular (PCR) tests. Materials and Methods: A total of 18 blood samples were collected from goats of BAUGF and tested by Rose Bengal Plate Test (RBPT), the indirect enzyme-linked immunosorbent assay (i-ELISA), and polymerase Chain Reaction (PCR). Results: Serological analysis of 18 goats revealed decreasing positivity rates across methods: 33.33% (Rapid Kit), 22.22% (Rose Bengal Plate Test), and 16.67% (both ELISA and PCR), with females (23.07%) showing higher infection rates favorable with all the used four tests, than males, which are negative with two tests (RKT & RBPT), and positive with two tests (i-ELISA & PCR) with only one case (20.0%) positive. Of the 18 goats screened, PCR detected B. melitensis-specific omp2 genes in 11.11% of samples. Conclusions: Serological evidence of caprine brucellosis in goats and molecular detection of B. melitensis in Bangladesh warrant regular screening, surveillance, and reporting of disease in goats and human risk groups.