Journal of
Veterinary Medicine and Animal Health

  • Abbreviation: J. Vet. Med. Anim. Health
  • Language: English
  • ISSN: 2141-2529
  • DOI: 10.5897/JVMAH
  • Start Year: 2009
  • Published Articles: 400

Article in Press

Comparative Pathology and Molecular Typing of Mycobacteria Isolated from lesioned tissues in State Dairy Farms, Central Ethiopia

  •  Received: 15 November 2019
  •  Accepted: 30 March 2020
BTB is a chronic infectious disease of animals characterized by the formation of specific granulomatous lesions or tubercles in tissues and organs. It is caused predominantly by Mycobacterium bovis (M. bovis) by slowly growing non photochromogenic bacilli members of the M.tuberculosis complex. Comparative tuberculin test positive dairy cattle were subjected to postmortem examination to characterize the severity of pathology and tropism of the disease among different cattle breeds. Detailed postmortem examination and inspection was performed on different lymph nodes and organs by palpation and incision under light. Grossly suspicious TB lesions were collected and characterized. Severity of pathology, bacteriological culture, multiplex PCR, region of difference PCR and spolygotyping were conducted following the standard procedure to identify the circulating species and strains. Suggestive tuberculous gross lesion was recorded from 95.35% (41/43) of animals. The mean pathology score was higher in mesenteric lymph node (Mean± SEM, 1.32 ±0.22 followed by caudal mediastinal lymph node (1.27 ±0.20), respectively. The severity of tuberculous lesions in different lymph nodes were statistically significant (p<0.05.The mean pathology score was high in Boran breed (12.27±1.96) with the median score and range of 11(5-27) which was statistically significant (p<0.05). Molecular analysis result reveal, M.tuberculosis and M. bovis species, from which fourteen (14) M. bovis and the remaining 2 were M tuberculosis. Single strain of SB0912 and SIT54 of M.bovis and M.tuberculosis respectively were identified by further characterization of the isolates through spolygotyping. In conclusion, isolation of a single strain of M. bovis from these farms could suggest the circulation of this strain in these farms by movement of dairy cattle from one farm to another and warrants strict biosecurity on animal movement. While the isolation of M .tuberculosis from cattle tissues could suggest its transmission from animal attendants to the infected cattle

Keywords: Bovine tuberculosis, M.tuberculosis, Molecular Diagnosis, Pathology scoring, State Dairy Farms, Central Ethiopia