title: Preliminary observations on Mycobacterium spp. in dairy cattle in Ecuador.
abstract: This study evaluated bovine tuberculosis in Mejia canton, a major dairy cattle production region in Ecuador. Randomly selected cattle (1,012 from 59 farms) classified according to herd size were tested by the single tuberculin test (STT). Sixty days later, positive reactors were tested again by the comparative tuberculin test (CTT). In addition, tissue samples from two STT-CTT-positive reactors detected on a farm were obtained in a local slaughterhouse and analyzed bacteriologically. A total of 4.24% of the cattle were positive in the STT and 3.85% were positive in the CTT, with the highest number (7.95%) in large herds versus 3.4% in medium herds and 0.3% in small herds. Mycobacterium bovis was isolated from mesenteric lymph nodes and lungs of one animal. A 16S ribosomal RNA-based polymerase chain reaction confirmed culture results and differentiated mycobacteria other than M. tuberculosis. This study confirms the zoonotic importance of tuberculosis in Ecuadorian dairy cattle with herd size likely to be a crucial parameter in the prevalence of the disease. The implementation of a national control program is necessary and should be based on the detection of positive cattle by STT in combination with CTT.
authors.affiliation: International Centre for Zoonoses, Central University of Ecuador, Quito, Ecuador. fproanio-ciz@ac.uce.edu.ec
authors.forename: Freddy
authors.initials: F
authors.lastname: Proaño-Perez
authors.forename: Leen
authors.initials: L
authors.lastname: Rigouts
authors.forename: Jef
authors.initials: J
authors.lastname: Brandt
authors.forename: Pierre
authors.initials: P
authors.lastname: Dorny
authors.forename: Jorge
authors.initials: J
authors.lastname: Ron
authors.forename: Maria-Augusta
authors.initials: MA
authors.lastname: Chavez
authors.forename: Richar
authors.initials: R
authors.lastname: Rodriguez
authors.forename: Krista
authors.initials: K
authors.lastname: Fissette
authors.forename: Anita
authors.initials: A
authors.lastname: Van Aerde
authors.forename: Françoise
authors.initials: F
authors.lastname: Portaels
authors.forename: Washington
authors.initials: W
authors.lastname: Benitez-Ortiz
mesh_terms: D000818:Animals; D002417:Cattle; D017931:DNA Primers / Q000737:chemistry; D003612:Dairying; D004484:Ecuador / Q000453:epidemiology; D005260:Female; D008168:Lung / Q000382:microbiology; D008198:Lymph Nodes / Q000382:microbiology; D009161:Mycobacterium / Q000145:classification* / Q000302:isolation & purification; D009163:Mycobacterium bovis / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014374:Tuberculin Test / Q000662:veterinary; D014380:Tuberculosis, Bovine / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology*; D015047:Zoonoses / Q000382:microbiology
chemical_list: D017931:DNA Primers; D012336:RNA, Ribosomal, 16S