title: Pathogenesis of Mycobacterium bovis infection in American bison.
abstract: Eighteen 12-month-old bison were randomly placed in each of 3 groups (6 animals/group): group-1 bison were exposed to live Mycobacterium bovis, group-2 bison were inoculated with killed M bovis in oil, and group-3 bison were noninfected controls. Six, 6-month-old, tuberculin test-negative calves were placed (pen contact) with group-1 bison 30 days after exposure to M bovis. Tuberculin skin test responses (caudal fold and/or comparative cervical) were detected in all bison in groups 1 and 2 at 2, 4, 6, 10, and 12 months. Tuberculin skin test responses were observed in 2 of 6 calves at 9 and 11 months after pen contact with M bovis-exposed bison (group 1). Statistically significant lymphocyte blastogenic responses to M bovis purified protein derivative were detected in group-1 bison exposed to live M bovis at 2 months after exposure (P less than 0.025). Significant ELISA reactions were detected in sera of bison at 2 months after exposure to killed M bovis in oil (P less than 0.005) and in bison 2 months after exposure to live M bovis (P less than 0.01). Significant tuberculin skin responses, ELISA reactions, or lymphocyte blastogenic responses to M bovis purified protein derivative were not observed in the 6 control bison. Grossly visible tuberculous lesions were observed in lymph nodes and/or lung collected at necropsy in 4 of 6 bison at 12 months after exposure to live M bovis. Microscopic granulomas compatible with tuberculosis were detected in 5 of 6 bison; M bovis was isolated from tissues of each of the 6 bison.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames 50011.
authors.forename: C O
authors.initials: CO
authors.lastname: Thoen
authors.forename: K J
authors.initials: KJ
authors.lastname: Throlson
authors.forename: L D
authors.initials: LD
authors.lastname: Miller
authors.forename: E M
authors.initials: EM
authors.lastname: Himes
authors.forename: R L
authors.initials: RL
authors.lastname: Morgan
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D001188:Artiodactyla; D002417:Cattle; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D008198:Lymph Nodes / Q000473:pathology; D008213:Lymphocyte Activation; D008297:Male; D009163:Mycobacterium bovis / Q000276:immunology; D011897:Random Allocation; D014374:Tuberculin Test / Q000662:veterinary; D014376:Tuberculosis / Q000175:diagnosis / Q000209:etiology / Q000635:transmission / Q000662:veterinary*; D014380:Tuberculosis, Bovine / Q000635:transmission
chemical_list: D000907:Antibodies, Bacterial