%0 Journal Article
%T Shared Bacterial and Viral Respiratory Agents in Bighorn Sheep (Ovis canadensis), Domestic Sheep (Ovis aries), and Goats (Capra hircus) in Montana
%A David S. Miller
%A Glen C. Weiser
%A Keith Aune
%A Brent Roeder
%A Mark Atkinson
%A Neil Anderson
%A Thomas J. Roffe
%A Kim A. Keating
%A Phillip L. Chapman
%A Cleon Kimberling
%A Jack Rhyan
%A P. Ryan Clarke
%J Veterinary Medicine International
%D 2011
%I Hindawi Publishing Corporation
%R 10.4061/2011/162520
%X Transmission of infectious agents from livestock reservoirs has been hypothesized to cause respiratory disease outbreaks in bighorn sheep (Ovis canadensis), and land management policies intended to limit this transmission have proven controversial. This cross-sectional study compares the infectious agents present in multiple populations of bighorn sheep near to and distant from their interface with domestic sheep (O. aries) and domestic goat (Capra hircus) and provides critical baseline information needed for interpretations of cross-species transmission risks. Bighorn sheep and livestock shared exposure to Pasteurellaceae, viral, and endoparasite agents. In contrast, although the impact is uncertain, Mycoplasma sp. was isolated from livestock but not bighorn sheep. These results may be the result of historic cross-species transmission of agents that has resulted in a mosaic of endemic and exotic agents. Future work using longitudinal and multiple population comparisons is needed to rigorously establish the risk of outbreaks from cross-species transmission of infectious agents. 1. Introduction Bighorn sheep (Ovis canadensis) experienced substantial decreases in population numbers and range in the 19th and the early 20th centuries, and subsequent recovery efforts have often been limited by large-scale die-offs [1¨C3]. These initial population declines were associated with settlement of western North America and were attributed to unregulated hunting, competition for forage with domestic sheep (O. aries) and other livestock, and disruption of historic bighorn sheep migration patterns due to development. Clinical disease was apparently unimportant or was underreported in these early declines, though die-offs of bighorn sheep associated with sheep scab (Psoroptes sp.) were reported following settlement [4, 5]. Bighorn sheep die-offs associated with pneumonia were reported in the 1920s and 1930s [6¨C10]. These early reports and subsequent work largely focused on lungworm (Protostrongylus sp.) as the primary infectious agent, although the involvement of Pasteurella sp., Corynebacterium pyogenes (currently Arcanobacterium pyogenes), and other host and environmental determinants were also noted as potential causes of respiratory disease. Subsequently, inconsistent association of lungworm with respiratory disease in bighorn sheep, as well as further evidence for Pasteurella sp. as the cause of pneumonia, led to a focus on pasteurellosis as a cause of respiratory disease outbreaks [11¨C14]. This research included evidence that Pasteurella sp. strains from clinically
%U http://www.hindawi.com/journals/vmi/2011/162520/