title: Pathologic changes and microorganisms found in bighorn sheep during a stress-related die-off.
abstract: An all-age die-off of Rocky Mountain bighorn sheep (Ovis c. canadensis Shaw) occurred from late October 1980 through March 1981 in Waterton Canyon, Colorado, with a loss of 75 to 85% of the sheep. The cause of death was a subacute to chronic bronchopneumonia and the primary etiologic agents isolated from the respiratory system were a Pasteurella sp., P. multocida, Corynebacterium pyogenes, and Protostrongylus stilesi Dikmans, 1931. The underlying predisposing factors that initiated this die-off were believed to be related to multiple chronic environmental stressors associated with the building of a dam which included human contact, vehicular traffic, atmospheric dust, noise and harassment. The die-off was succeeded by a 100% lamb mortality the following summer and a 67% lamb mortality the next two summers. The pneumonia found in these lambs was similar to that found in adult sheep during the previous die-off, except that mature lungworms were absent.
mesh_terms: D000818:Animals; D001996:Bronchopneumonia / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D003354:Corynebacterium Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary; D003643:Death; D008168:Lung / Q000382:microbiology / Q000473:pathology; D009349:Nematode Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary; D010326:Pasteurella Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary; D012756:Sheep; D012757:Sheep Diseases / Q000209:etiology* / Q000382:microbiology / Q000473:pathology; D013312:Stress, Physiological / Q000150:complications / Q000662:veterinary*; D013320:Strongyloidea