title: Sheep as a Potential Source of Bovine TB: Epidemiology, Pathology and Evaluation of Diagnostic Techniques.
abstract: Bovine tuberculosis (TB) infection is infrequently diagnosed in sheep. Most reports are from single individual cases or flock outbreaks. However, in Spain several outbreaks have been reported recently, all of which had epidemiological links with TB-infected cattle herds. A total of 897 sheep suspected of being infected with TB and belonging to 23 flocks cohabiting with TB-infected cattle herds and/or goats were tested between 2009 and 2013 in Galicia (north-western Spain), using pathological, immunological and molecular techniques. Of these, 50.44% were positive by culture, 83.23% by histopathology and 24.92%, 4.86% and 59.42% by single intradermal tuberculin test (SITT), interferon-γ and ELISA, respectively. Results suggest that in circumstances akin to those in our study, sheep may be considered as a potential source of TB. We conclude that under similar conditions, serious consideration should be given to TB testing sheep, as they may represent a potential risk to other susceptible co-habiting species. The SITT and ELISA are recommended as the simplest and most cost-effective initial approaches for the diagnosis of TB in sheep under field conditions. However, when possible, interferon-γ should be applied to increase sensitivity.
authors: Subdirección de Ganadería, Consellería do Medio Rural, Xunta de Galicia, Edificio Administrativo San Caetano, Santiago de Compostela A Coruña, Spain.
authors: M
authors: M
authors: Muñoz-Mendoza
authors: Centro de Vigilancia Sanitaria Veterinaria (VISAVET) y Departamento de Sanidad Animal (Facultad de Veterinaria), Universidad Complutense, Madrid, Spain.
authors: B
authors: B
authors: Romero
authors: Centro de Biotecnología Animal, SERIDA, Servicio Regional de Investigación y Desarrollo Agroalimentario, Gijón, Spain.
authors: A
authors: A
authors: Del Cerro
authors: SaBio IREC (CSIC - UCLM - JCCM), Ciudad Real, Spain.
authors: C
authors: C
authors: Gortázar
authors: Facultad de Veterinaria, Universidad de León, León, Spain.
authors: J F
authors: JF
authors: García-Marín
authors: Departamento de Biología Molecular del Laboratorio de Sanidad y Producción Animal de Galicia, Xunta de Galicia, Lugo, Spain.
authors: S
authors: S
authors: Menéndez
authors: Subdirección de Ganadería, Consellería do Medio Rural, Xunta de Galicia, Edificio Administrativo San Caetano, Santiago de Compostela A Coruña, Spain.
authors: J
authors: J
authors: Mourelo
authors: Centro de Vigilancia Sanitaria Veterinaria (VISAVET) y Departamento de Sanidad Animal (Facultad de Veterinaria), Universidad Complutense, Madrid, Spain.
authors: L
authors: L
authors: de Juan
authors: Subdirección General de Sanidad e Higiene Animal y Trazabilidad, Dirección General de Sanidad de la Producción Agraria, Ministerio de Agricultura, Alimentación y Medio Ambiente, Madrid, Spain.
authors: J L
authors: JL
authors: Sáez
authors: National Wildlife Management Centre, Animal and Plant Health Agency (APHA), Gloucestershire, UK.
authors: R J
authors: RJ
authors: Delahay
authors: Centro de Biotecnología Animal, SERIDA, Servicio Regional de Investigación y Desarrollo Agroalimentario, Gijón, Spain. abalseiro@serida.org.
authors: A
authors: A
authors: Balseiro
mesh_terms: D000818:Animals; D002417:Cattle; D004196:Disease Outbreaks / Q000662:veterinary*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D006041:Goats; D007371:Interferon-gamma; D012756:Sheep; D013030:Spain / Q000453:epidemiology; D014374:Tuberculin Test / Q000379:methods*; D014380:Tuberculosis, Bovine / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology*
chemical_list: D007371:Interferon-gamma
keywords: bovine tuberculosis; diagnostic techniques; epidemiology; pathology; sheep