Serological and molecular analysis for brucellosis in selected swine herds from Southern India.

ABSTRACT

BACKGROUND: Swine brucellosis is a zoonotic disease caused by Brucella suis. The study describes the occurrence of brucellosis in two organized piggeries in Southern India. METHODS: A total of 585 serum samples comprising 575 from pigs and 10 from animal handlers were collected and tested by serological tests and PCR. Tissue samples were collected for isolation of the pathogen. RESULTS: Out of 575 serum samples screened, 236 (41.04%) were positive for brucellosis by both Rose Bengal plate test (RBPT) and indirect ELISA (iELISA) and 47 (8.17) samples showed Brucella DNA amplification by genus specific PCR. The sows those aborted and 19 boars with orchitis were seropositive for brucellosis indicating association of clinical symptoms with brucellosis seropositivity. Two of 10 pig handlers were positive by RBPT and showed significant serum agglutination test (SAT) titres of >1160 and 1320. B. suis bvI was isolated and identified by biochemical tests and confirmed by amplification Brucella genus and Bruce ladder PCRs from vaginal and testicular samples. CONCLUSIONS: The introduction of untested breeding boars in the farms might have resulted in the disease transmission and spread. The present study highlighted the diagnosis of B. suis bvI as a cause of abortions in the pigs and occupational exposure to farm personnel.