title: Identification of Mycobacterium bovis in bovine clinical samples by PCR species-specific primers.
abstract: Tuberculosis, caused by Mycobacterium bovis is emerging as the most important disease affecting cattle. Furthermore, it results in a major public health problem when transmitted to humans. Due to its difficult and non-specific diagnosis, M. bovis has been declared to be one of the etiologic agents causing significant economic loss in the cattle industry. Our group evaluated a more rapid and specific method, based on a new polymerase chain reaction species-specific primers, which amplifies a 470-base pair fragment of the M. bovis genome. A total of 275 milk-producing cows were studied by intradermal tuberculin test (ITT) which gave 184 positive and 91 negative cases. From them, 50 animals were taken from a cattle ranch free of tuberculosis. Three different samples were collected from each animal (blood, nasal mucus, and milk). Positive results were obtained from 26 animals by PCR (11.4%), 1 by bacteriological culturing (0.4%) and 1 by bacilloscopy (0.4%). This finding suggests, as in previous reports, that ITT, normally used for bovine tuberculosis detection, has the inconvenience of having a broad range of specificity and sensitivity, and the PCR technique is a more specific and sensitive test to detect infection associated with M. bovis. Therefore, we propose this PCR assay as a useful tool in the epidemiological characterization of infected animals in areas considered to be at high risk of transmission.
authors.affiliation: Department of Molecular Biology, Instituto de Inmunología, Hospital San Juan de Dios, Universidad Nacional de Colombia, Santafé de Bogotá.
authors.forename: R E
authors.initials: RE
authors.lastname: Romero
authors.forename: D L
authors.initials: DL
authors.lastname: Garzón
authors.forename: G A
authors.initials: GA
authors.lastname: Mejía
authors.forename: W
authors.initials: W
authors.lastname: Monroy
authors.forename: M E
authors.initials: ME
authors.lastname: Patarroyo
authors.forename: L A
authors.initials: LA
authors.lastname: Murillo
mesh_terms: D000818:Animals; D002417:Cattle; D003105:Colombia / Q000453:epidemiology; D017931:DNA Primers; D005260:Female; D016679:Genome, Viral; D006801:Humans; D008892:Milk; D009163:Mycobacterium bovis / Q000235:genetics / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods; D014380:Tuberculosis, Bovine / Q000175:diagnosis* / Q000453:epidemiology; D015047:Zoonoses
chemical_list: D017931:DNA Primers