Detection of virulence associated gene in Brucella abortus from blood samples of cows in District Swat of Khyber Pakhtunkhwa, Pakistan

Abstract

Brucella abortus is a gram-negative, non-spore-forming bacteria that can cause infection in humans and many species of animals. The present study investigated the molecular detection of Brucella species, and the frequency of virulent genes (vir B and ure) in the Brucella species circulating in livestock of the district Swat Khyber Pakhtunkhwa, Pakistan. Blood samples were collected from infected cows and buffaloes of the two tehsils of district Swat. DNA was extracted from a blood sample and subjected to genus and species-specific primer of Brucella using PCR assay. The Brucella species DNA was then screened for the presence of virulent genes. PCR assay using specific primers confirmed genus Brucella, species abortus, and detected virulence-associated gene virB and ure operon in B. abortus. Out of the total tested samples, 22.8% were positive for the Brucella genus and 68.7% for B. abortus. The virB virulent gene and ure gene frequency were 72.7% and 40% respectively. The high frequency of virulent genes in B. abortus indicated a circulation of virulent strains of B.abortus in livestock in reported areas.