title: Comparative pathology of the natural infections by Mycobacterium bovis and by Mycobacterium caprae in wild boar (Sus scrofa).
abstract: The potential role of wild animals in the maintenance and spread of tuberculosis (TB) infection in domestic livestock is of particular importance in countries where eradication programs have substantially reduced the incidence of bovine tuberculosis but sporadic outbreaks still occur. Mycobacterium bovis is the agent mainly isolated in wildlife in Spain, but recently, infections by Mycobacterium caprae have increased substantially. In this study, we have analysed 43 mandibular lymph nodes samples containing TB-like lesions from 43 hunted wild boar from Madrid and Extremadura (central and south-western regions of Spain). After isolation, identification and typing of Mycobacterium tuberculosis complex isolates, we found that 23 mandibular lymph nodes involved M. caprae infections and 20 M. bovis. The lesions were compared for histopathology (different granuloma stage and number of multinucleated giant cells (MNGCs)), and acid-fast bacilli (AFBs) were quantified in the Ziehl-Neelsen-stained slides. Granulomas produced by M. caprae showed more stage IV granulomas, more MNGCs and higher AFBs counts than those induced by M. bovis. In conclusion, lesions caused by M. caprae would be more prone to the excretion of bacilli, and infected animals result as a high-risk source of infection for other animals.
authors.affiliation: Red de Grupos de Investigación Recursos Faunísticos, Facultad de Veterinaria, Universidad de Extremadura, Cáceres, Spain. walgarjim@unex.es
authors.forename: W L
authors.initials: WL
authors.lastname: García-Jiménez
authors.forename: J M
authors.initials: JM
authors.lastname: Benítez-Medina
authors.forename: P
authors.initials: P
authors.lastname: Fernández-Llario
authors.forename: J A
authors.initials: JA
authors.lastname: Abecia
authors.forename: A
authors.initials: A
authors.lastname: García-Sánchez
authors.forename: R
authors.initials: R
authors.lastname: Martínez
authors.forename: D
authors.initials: D
authors.lastname: Risco
authors.forename: A
authors.initials: A
authors.lastname: Ortiz-Peláez
authors.forename: F J
authors.initials: FJ
authors.lastname: Salguero
authors.forename: N H
authors.initials: NH
authors.lastname: Smith
authors.forename: L
authors.initials: L
authors.lastname: Gómez
authors.forename: J
authors.initials: J
authors.lastname: Hermoso de Mendoza
mesh_terms: D000818:Animals; D004196:Disease Outbreaks / Q000662:veterinary*; D006099:Granuloma / Q000382:microbiology / Q000473:pathology; D008198:Lymph Nodes / Q000382:microbiology / Q000473:pathology; D009161:Mycobacterium / Q000145:classification / Q000302:isolation & purification / Q000472:pathogenicity*; D013030:Spain / Q000453:epidemiology; D034421:Sus scrofa / Q000382:microbiology*; D013552:Swine / Q000382:microbiology; D013553:Swine Diseases / Q000382:microbiology* / Q000473:pathology / Q000635:transmission; D014376:Tuberculosis / Q000453:epidemiology / Q000473:pathology* / Q000662:veterinary*