title: Susceptibility of Balb/c, C57/B6 and C57/B10 mice to infection with Mycobacterium paratuberculosis.
abstract: Balb/C, C57/B10 and C57/B6 mice were examined for their susceptibility to disseminated Mycobacterium paratuberculosis infection after intraperitoneal inoculation with a suspension of organisms containing mineral oil. Animals were examined monthly by histopathology and bacterial tissue counts of liver and spleen over a 6-month period. Only Balb/c mice maintained a steady infection with an average of 4.1 x 10(5) +/- 7.8 x 10(3) and 8.1 x 10(5) +/- 2.6 x 10(4) colony forming units (cfu) per gram of liver and spleen, respectively, during the course of the study. In contrast, C57/B10 mice reduced the bacterial counts in the liver and spleen from 6.8 x 10(4) and 1.3 x 10(5) to 7.1 x 10(2) and 4.3 x 10(3), respectively during the first 120-150 days after infection. The reduction in cfu was associated with the development of caseous necrotic lesions. C57/B10 mice were of intermediate resistance, slowly reducing cfu in the liver, but not the spleen, during the 6-month period. Balb/c was found to be a suitable mouse strain for the study of chronic M. paratuberculosis infection.
authors.affiliation: Department of Medicine, Rhode Island Hospital, Providence.
authors.forename: R J
authors.initials: RJ
authors.lastname: Chiodini
authors.forename: C D
authors.initials: CD
authors.lastname: Buergelt
mesh_terms: D000818:Animals; D015169:Colony Count, Microbial; D004198:Disease Susceptibility; D005260:Female; D006099:Granuloma / Q000209:etiology / Q000382:microbiology / Q000473:pathology*; D008099:Liver / Q000382:microbiology / Q000473:pathology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D010283:Paratuberculosis / Q000150:complications / Q000382:microbiology / Q000473:pathology*; D010532:Peritoneal Diseases / Q000209:etiology / Q000382:microbiology / Q000473:pathology*; D013045:Species Specificity; D013154:Spleen / Q000382:microbiology / Q000473:pathology*; D013997:Time Factors