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Updated: Jul 17, 2026
13:42
Clinical Examination Protocol to Detect Atypical and Classical Scrapie in Sheep
Published on: January 19, 2014
Advanced survival models for risk-factor analysis in scrapie
Fabien Corbière1,2, Francis Barillet3, Olivier Andréoletti2
1EMI 0338 (Biostatistique), Institut de Santé Publique et Développement, Université Victor Segalen Bordeaux 2, 146 rue Léo Saignat, 33076 Bordeaux Cedex, France.
The Journal of General Virology
|January 26, 2007
Summary
Scrapie outbreaks in sheep are complex due to long incubation periods and flock management. PrP genotype influences infection risk and onset age, but other factors like agent type and management also impact scrapie dynamics.
Area of Science:
- Veterinary Epidemiology
- Animal Genetics
- Prion Diseases
Background:
- Scrapie epidemiology is challenging due to long incubation periods and flock management complexities.
- Accurate studies require long-term monitoring and consideration of genetic factors.
Purpose of the Study:
- To investigate the epidemiological dynamics of scrapie in Manech red-faced sheep.
- To assess the influence of PrP genotype and flock origin on scrapie incidence and incubation period.
Main Methods:
- Longitudinal study of 641 sheep across six affected flocks over 6-9 years.
- Monitoring clinical scrapie cases and post-mortem diagnosis of transmissible spongiform encephalopathies.
- Analysis using a 'mixture cure model' incorporating PrP genotype and flock origin.
Main Results:
- ARR heterozygote sheep showed reduced infection risk and later onset compared to ARQ/ARQ.
- VRQ haplotype correlated with increased infection risk but not shorter incubation periods.
- Flock origin significantly impacted incubation periods, independent of incidence rates.
Conclusions:
- PrP genotype is a key factor in scrapie susceptibility and clinical manifestation.
- Flock management and potentially the nature of the infectious agent significantly influence scrapie's epidemiological patterns.
- Further research into non-genetic factors is crucial for understanding and controlling scrapie outbreaks.
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