title: Molecular Identification of Mycobacterium Species of Public Health Importance in Cattle in Zimbabwe by 16S rRNA Gene Sequencing.
abstract: Mycobacterium species are naturally found in the environment as well as in domestic animals such as cattle. So far, more than 150 species of Mycobacterium, some of which are pathogenic, have been identified. Laboratory isolation, detection and identification of Mycobacterium species are therefore critical if human and animal infections are to be controlled. The objective of this study was to identify Mycobacterium species isolated in cattle in Zimbabwe using 16S ribosomal RNA gene amplification and sequencing. A total of 134 cow dung samples were collected throughout Zimbabwe and mycobacteria were isolated by culture. Only 49 culture isolates that were found to be acid-fast bacilli positive by Ziehl-Neelsen staining. The 16S rRNA gene was successfully amplified by PCR in 41 (84%) of the samples. There was no amplification in 8 (16%) of the samples. Out of the 41 samples that showed amplification, 26 (63%) had strong PCR bands and were selected for DNA sequencing. Analysis of the DNA sequences showed that 7 (27%) belonged to Mycobacterium neoaurum, 6 (23%) belonged to Mycobacterium fortuitum, 3 (12%) to Mycobacterium goodii, 2 (1%) to Mycobacterium arupense, 2 (1%) to Mycobacterium peregrinum or M. septicum and 1 isolate (0.04%) to Mycobacterium elephantis. There were 5 (19%) isolates that were non-mycobacteria and identified as Gordonia terrae, a close relative of Mycobacterium. The study therefore provided a molecular basis for detection and identification of Mycobacterium species in animals and humans.
authors.affiliation: Department of Medical Microbiology, University of Zimbabwe, Harare, Zimbabwe ; Department of Applied Biology and Biochemistry, National University of Science and Technology, Bulawayo, Zimbabwe.
authors.forename: Leah
authors.initials: L
authors.lastname: Padya
authors.affiliation: Department of Medical Microbiology, University of Zimbabwe, Harare, Zimbabwe.
authors.forename: Nyasha
authors.initials: N
authors.lastname: Chin'ombe
authors.affiliation: Department of Medical Microbiology, University of Zimbabwe, Harare, Zimbabwe.
authors.forename: Marcelyn
authors.initials: M
authors.lastname: Magwenzi
authors.affiliation: Department of Applied Biology and Biochemistry, National University of Science and Technology, Bulawayo, Zimbabwe.
authors.forename: Joshua
authors.initials: J
authors.lastname: Mbanga
authors.affiliation: Department of Medical Microbiology, University of Zimbabwe, Harare, Zimbabwe.
authors.forename: Vurayai
authors.initials: V
authors.lastname: Ruhanya
authors.affiliation: Department of Medical Microbiology, University of Zimbabwe, Harare, Zimbabwe.
authors.forename: Pasipanodya
authors.initials: P
authors.lastname: Nziramasanga
keywords: 16S rRNA gene; Mycobacterium species; cattle; cow dung; sequencing.