Progress 06/03/02 to 05/01/07
Outputs
Progress Report Objectives (from AD-416) The objective of this project is to delineate the prion profiles of chronic wasting disease in elk and white tailed deer. Approach (from AD-416) ARS and the cooperator have developed and validated an immunohistochemical diagnostic assay for chronic wasting disease, based on detection of PrP-res, the marker protein for the disease. The assay is typically applied to the tonsil and to one specific region of the brain in deer and elk, although the kinetics and anatomic location of PrP- res have not been reported in cervid species other than mule deer. The current project addresses this problem through a systematic investigation of PrP-res in the brain and extraneural tissue of infected elk and white tailed deer. The profiles of chronic wasting disease in these species will be defined through a combination of histology, immunohistochemistry, protein chemistry, genetics, and population epidemiology approaches. BSL- 1; 9-04-06. Documents SCA with CO State U. Formerly 5348-32000-021-01S December 2006. Significant Activities that Support Special Target Populations This report serves to document research conducted under a specific cooperative agreement between ARS and Colorado State University. Additional details of research can be found in the report for the parent project 5438-32000-026-00D Transmissible Spongiform Encephalopathies: The Role of Genetics, Strain Variation, and Environmental Contamination in Disease Control. Our earlier work demonstrated that elk with the prion genotype 132LL were underrepresented in infected elk, although the genotype is not protective in captive elk. We have not demonstrated that the incubation time for 132LL elk is nearly triple that of elk with the 132MM genotype following experimental oral inoculation. Further, the prion protein processing in 132LL elk results in a novel biochemical signature. These findings are important for regulatory officials when designing monitoring and movement programs and provide new insights into prion protein processing in ruminant livestock. The project is monitored through regular conference calls and an annual collaborator meeting.
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Progress 10/01/05 to 09/30/06
Outputs
Progress Report 4d Progress report. This report serves to document research conducted under a specific cooperative agreement between ARS and Colorado State University. Additional details of research can be found in the report for the parent project 5348-32000-021-00D BSE and other TSES Ruminant Herbivores: Diagnosis, Transmission and Genetics. Our earlier work demonstrated that elk with the prion genotype 132LL were underrepresented in infected elk although the genotype is not fully protective in captive elk. We have now demonstrated that the 132L allele extends the incubation time in elk, resulting in a doubling of the preclinical incubation period. This finding is important for regulatory agencies and producers in states in which clinical disease is considered in selection of animals for surveillance testing.
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Progress 10/01/04 to 09/30/05
Outputs
4d Progress report. This report serves to document research conducted under a specific cooperative agreement between ARS and Colorado State University. Additional details of research can be found in the report for the parent project 5348-32000-021-00D BSE and other TSES Ruminant Herbivors: Diagnosis, Transmission and Genetics. Chronic wasting disease has traditionally been diagnosed by histological examination of the brain, although in TSE-infected sheep and mule deer, the brain accumulates the marker prion protein months to years after the lymph nodes. In collaboration with Colorado State University (Spraker) and the Canadian Food Inspection Agencywe established that the tonsils and retropharyngeal lymph nodes of Rocky Mountain elk do not provide the reliable early diagnostic target observed in white tailed deer and mule deer. Therefore, accurate diagnosis of elk requires examination of both the brain and the lymph node. Further, although our earlier work
demonstrated that elk with the prion genotype 132LL were underrepresented in infected elk, we confirmed one case of CWD in an elk of this genotype, demonstrating that these elk are not invariably resistant to disease.
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Progress 10/01/03 to 09/30/04
Outputs
4. What were the most significant accomplishments this past year? D. What were the most significant accomplishments this past year? This report serves to document research conducted under a specific cooperative agreement between ARS and Colorado State University. Chronic wasting disease has traditionally been diagnosed by histological examination of the brain, although in TSE-infected sheep and mule deer, the brain accumulates the marker prion protein months to years after the lymph nodes. In collaboration with Colorado State University (Spraker), the Canadian Food Inspection Agency, and the Nebraska Division of Game and Parks, we established that the tonsils and retropharyngeal lymph nodes of white tailed deer are a reliable early indicator of infection. However, we demonstrated that a relatively high percentage of elk with positive tests on brain tissue have negative tests of the retropharyngeal lymph node. Therefore, accurate diagnosis of elk requires
examination of both the brain and the lymph node. This report serves to document research conducted under a specific cooperative agreement between ARS and Colorado State University. Additional details of research can be found in the report for the parent project 5348-32000-021-00D Animal Health.
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