Molecular diagnosis of Brucella abortus from clinical samples of cattle and buffaloes Modi A.N.1, Chauhan H.C.1,*, Patel A.C.1, Patel S.S.1, Shrimali M.D.2, Sharma K.K.1, Shah J.D.1, Mohapatra S.K.2, Chandel B.S.2 1Department of Veterinary Microbiology, College of Veterinary Science and Animal Husbandry, Sardarkrushinagar Dantiwada Agricultural University (Now under Kamdhenu University, Gandhinagar) Sardarkrushinagar-385506, Gujarat, India 2Department of Animal Biotechnology, College of Veterinary Science and Animal Husbandry, Sardarkrushinagar Dantiwada Agricultural University (Now under Kamdhenu University, Gandhinagar) Sardarkrushinagar-385506, Gujarat, India *Corresponding author E-mail id: hcchauhan1972@kamdhenuuni.edu.in
Online published on 29 August, 2023. Abstract Brucellosis is essentially a disease of sexually mature animals, with a predilection for ungulate placenta, fetal fluids, joints, and testes of male animals. Considering Brucella abortus as the principal species affecting cattle and buffaloes, due to its zoonotic importance and the difficulties observed in serological and bacteriological diagnosis, molecular diagnosis of B. abortus was attempted in samples collected from these target host species. A total of 204 samples were collected from cattle (N=121) and buffaloes (N=83) for screening through nucleic acid amplification methods. DNA was extracted from the samples and subjected to bcsp31 genus-specific PCR. As many as 6/121 (4.94%) and 4/83 (4.81%) samples were found positive for the genus Brucella in cattle and buffaloes, respectively. In total, 10 samples (vaginal swab-2, vaginal discharge-2, placenta-2, fetal stomach content-1, fetal liver-1, fetal heart blood-1, cotyledon-1) were found positive, resulting in an overall 4.9 percent positivity. Both genus-specific and species-specific gene-based PCR were performed using primers targeting bcsp31 and IS711, respectively. All the samples were confirmed to be positive for Brucella abortus. The samples that were detected positive in conventional genus PCR were also positive for Brucella in SYBR green and TaqMan probe-based real-time PCR and LAMP assay. Furthermore, in the Bruce ladder multiplex PCR, 5 bands of 152 bp, 450 bp, 587 bp, 794 bp, and 1682 bp sizes were obtained, corresponding to Brucella abortus, and denoting the absence of the vaccine strain S-19. Top Keywords Brucellosis, Conventional PCR, Real-time PCR, Bruce ladder-Multiplex PCR, LAMP assay. Top |