Survey of cattle in northeast Colorado for evidence of chronic wasting disease: geographical and high-risk targeted sample.
A geographically targeted survey of potentially high-risk, adult cattle in chronic wasting disease (CWD)-endemic areas in Colorado was initiated to assess the possibility of the spread of CWD from deer to cattle under natural conditions. Surveyed cattle were sympatric with free-roaming deer in geographically defined areas where CWD occurs and where CWD prevalence has been estimated. To qualify for inclusion in the survey, cattle had to be at least 4 years old and had to have spent a minimum of 4 years in surveyed areas. Brains from culled cattle were examined microscopically and immunohistochemically for tissue alterations indicative of a transmissible spongiform encephalopathy (TSE). Two hundred sixty-two brains were suitable for evaluation and were found to lack changes indicative of a TSE infection. Prion deposition was not demonstrable using a method involving formic acid and proteinase-K treatment before application of monoclonal antibody to bovine prion protein (F99/97.6.1). Some incidental neuropathologic changes unrelated to those of TSEs were detected. Findings from this study suggest that large-scale spread of CWD from deer to cattle under natural range conditions in CWD-endemic areas of northeast Colorado is unlikely.
Department of Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Ft. Collins, CO 80523, USA.
Daniel H
DH
Gould
James L
JL
Voss
Michael W
MW
Miller
Annette M
AM
Bachand
Bruce A
BA
Cummings
Anthony A
AA
Frank
D000818:Animals; D001921:Brain / Q000378:metabolism / Q000473:pathology; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis* / Q000453:epidemiology* / Q000635:transmission; D003120:Colorado / Q000453:epidemiology; D003625:Data Collection; D005843:Geography; D012306:Risk; D034081:Wasting Disease, Chronic / Q000175:diagnosis* / Q000453:epidemiology* / Q000635:transmission