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Recently, multi-source feedlots in the prairie region of western Canada have experienced many cases of antibiotic resistant pneumonia, sometimes in association with multiple joint fibrinous arthritis. The lung lesions in these cases resemble those described in M. bovis infection.1 We have also observed vascular lesions, positive by immunohistochemistry for bovine virus diarrhea virus (BVDV), in the heart and lungs of some cattle. A retrospective immunohistochemical and histopathological study was done of animals of this type was submitted to the Western College of Veterinary Medicine between January 1995 and December 1998. Our objective was to determine frequency of occurrence and distribution of M. bovis, BVDV, and Haemophilus somnus in lungs and hearts of animals with lesions typical of this form of chronic pneumonia., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2000

The Canadian Cooperative Wildlife Health Centre (CCWHC) was established in 1992 as an organization among Canada's 4 veterinary colleges, with a mandate to apply veterinary medicine to wildlife management and conservation in Canada. A major function of the CCWHC is nation-wide surveillance of wild animal diseases. Disease surveillance is conceived as consisting of 4 different activities: detection, diagnosis, information management, and use of information. In the CCWHC surveillance program, detection of disease is carried out by a wide range of professional and avocational field personnel, and much effort is expended to stimulate and support this activity. Diagnosis is done by personnel of provincial and federal veterinary laboratories and the CCWHC. Information management is achieved through a national database of wildlife disease incidents developed and maintained by the CCWHC. Use of information is enabled through established channels for distribution of information derived from the surveillance program to persons responsible for wildlife programs and policies, and to the public. There has been a high demand for the services of the CCWHC since its establishment. The CCWHC responds to approximately 2000 requests for information annually, distributes its newsletter to over 1700 recipients, examines approximately 1200 wild animal submissions each year, and has accumulated records of over 5000 disease incidents in its database. Technical information from the CCWHC has benefited federal, provincial/territorial, and nongovernment wildlife agencies; endangered species recovery programs; federal and provincial veterinary services; and federal and provincial public health programs.

Mallard ducks (Anus platyrynchos) challenged with two isolates of Pasteurella multocida developed either acute or chronic lesions, depending on the isolate of P. multocida and the inoculation dose. Ducks that died acutely of avian cholera had lesions of a hemorrhagic septicemia with widespread vascular damage and focal necrosis in liver, spleen and other organs. Ducks that survived challenge developed chronic lesions in a variety of organs, including brain, lung, air sacs, joints, and eyes. Some surviving ducks sequestered bacteria within these loalized lesions and may be potential "carrier" birds. The possible pathogenesis of P. multocida infection in ducks is discussed.

Richardson's ground squirrels were infected with 1500 or 9000 sporocysts of Sarcocystis campestris from badgers. No lesions were found in animals killed one to three days postinfection (pi). Hepatitis and phlebitis of hepatic veins were present in animals killed between four and eight days pi. No meronts were detected in these animals, but the lesions suggested that a generation of merogony occurred in the hepatic veins. Meronts were found in endothelial cells in many tissues beginning on day 9 pi. They were most numerous on day 10 pi, and less so on day 11, and subsequently. Meronts were most numerous in the lung; none was found in liver or spleen. Four of ten squirrels infected with 1500 sporocysts in one trial died between days 11 and 13 pi. There were petechial hemorrhages in skeletal muscle, lung, serosal membranes, and brain in these animals, with microscopic evidence of pulmonary, myocardial, and brain injury. One animal infected with 9000 sporocysts had petechiae in the liver at six days pi. Foci of inflammation were visible in the myocardium and brain of animals killed to 64 days pi. This species may serve as an experimental model for sarcocystosis in domestic animals.