title: Naturally occurring Tyzzer's disease in a clean mouse colony: high mortality with coincidental cardiac lesions.
abstract: Light and electron microscopic examinations were performed on tissues from 12 young mice which were affected by naturally-occurring Tyzzer's disease. Eight of the 12 mice had cardiac lesions which have not previously been reported in mice and which caused a high mortality. The cardiac lesions were detected in mice which had severe and advanced intestinal lesions which penetrated the deeper mucosa and muscular layer with active regeneration of the mucosal epithelium. Periodical serological tests to monitor the bacterial and viral status of this colony showed that it was free of other agents of murine disease such as mouse hepatitis virus, Corynebacterium kutscheri and Salmonella spp. until the onset of Tyzzer's disease and that no mixed infection occurred at the onset. It is considered that an advanced intestinal lesion is essential for the formation of cardiac lesions in Tyzzer's disease in mice.
mesh_terms: D000818:Animals; D003967:Diarrhea / Q000401:mortality / Q000473:pathology / Q000662:veterinary*; D004196:Disease Outbreaks / Q000662:veterinary; D005260:Female; D007422:Intestines / Q000473:pathology; D008099:Liver / Q000473:pathology; D051379:Mice; D008815:Mice, Inbred Strains; D008854:Microscopy, Electron; D009206:Myocardium / Q000473:pathology*; D012376:Rodent Diseases / Q000473:pathology*; D012499:Sanitation