Swine were infected with Mycobacterium bovis to develop a model for pulmonary and disseminated tuberculosis in humans. Pigs were inoculated with various doses of M. boris by intravenous (iv), intratracheal (int), or tonsillar routes. Animals were euthanized between 17 and 60 days after inoculation, and tissues were collected for culture and histopathologic examination. Lesions of disseminated tuberculosis were found in pigs given 104 or 108 cfu of M. bovis iv or int; localized pulmonary disease was found in pigs given 102 or 103 cfu of M. bovis int. Lesions ranged from well- organized tubercles with coagulative necrosis, epithelioid macrophages, and fibrosis to large expansive tubercles with liquefactive necrosis and extracellular growth of M. bovis. Tuberculous meningitis was observed in animals given M. bovis iv. Swine infected with M. bovis are a useful animal model for elucidating the mechanisms of pathogenesis and host defense to tuberculosis in humans.
Bibliographical noteFunding Information:
Received 4 March 1997; revised 17 July 1997. Presented in part: International Symposium on Bovine Tuberculosis in Animals and Human Beings, College Park, Maryland, May 1995. Animal experiments were conducted at the National Animal Disease Center, which is accredited by the American Association for the Accreditation of Laboratory Animal Care. The experiments were reviewed and approved by the Institutional Animal Care and Use Committee as protocol 1246. Financial support: NIH (DA-08496). Reprints or correspondence: Dr. Carole A. Bolin, National Animal Disease Center, P.O. Box 70, 2300 N. Dayton Rd., Ames, IA 50010.