NR AXOV
AU Huelamo,T.; Gonzalo,I.; Parra,B.; Nevado,M.J.; Anadon,E.; Gomez-Tejedor,C.; Mayoral,T.
TI Atypical Scrapie Field Cases Characterization in Spanish Ovine Breeds
QU International Conference - Prion 2007 (26.-28.9.2007) Edinburgh International Conference Centre, Edinburgh, Scotland, UK - Book of Abstracts: Natural and Experimental Strains P02.32
IA http://www.prion2007.com/pdf/Prion Book of Abstracts.pdf
PT Konferenz-Poster
AB
Scrapie is a neurodegenerative, progressive and fatal illness affect to sheep and goat in a natural way. For all EU countries, Regulation (EC) No 999/2001 set specific rapid tests approved for TSE monitoring in bovine and small ruminants.
Further modifications of R. 999/2001 includes monitoring programmes for caprine and ovine samples, as well as approval of new specifics rapid post-mortem tests for TSE's and strain characterisation in small ruminants. Since active surveillance with specific methods for small ruminants samples have been established, number of called atypical scrapie cases has been increased in spanish ovine herds.
In the present work, we report atypical cases found in Spain during the last years and since the first one detected in 2003 (Mayoral T. et al. 2004). In 2006 at least 96 positive ovine cases have been detected, 65% classical cases and 35% atypical cases. These atypical cases show discordant results when screening, discriminatory and confirmatory methods are compared. Moreover, biochemical characteristics (resistance to the accumulated PrPsc to PK digestion, altered immunoblot profile and evidence of a lower band of PrPres around 12-11 KDa known to be associated with atypical scrapie) from atypical cases are clearly different from classical ones.
Also genotyping analysis and neuroanatomical studies (distribution of PrPsc aggregates detected by immunohistochemistry and histopathology) show differences between both groups. All atypical cases were genotyped and distribution of polymorphisms found were ARQ/ARQ 18%, ARQ/AHQ 21%, ARR/ARQ 29%, ARR/AHQ 14%, ARQ/ARH 6% and ARR/ARR 12% quite different from classical cases where near 92% samples were ARQ/ARQ. Biochemical and histopathological studies in spanish atypical isolates and its comparison with typical cases and Nor98 strain will also be shown for better understanding of these cases.
AD T. Huelamo, I. Gonzalo, B. Parra, M.J. Nevado, E. Anadon, T. Mayoral, Laboratorio Central de Veterinaria., TSEs Department, Spain; C. Gómez-Tejedor, Laboratorio Central de Veterinaria., Spain
SP englisch
PO Schottland