Serial passage of sheep scrapie inoculum in Suffolk sheep.
Scrapie is a naturally occurring fatal neurodegenerative disease of sheep and goats. Susceptibility to the disease is partly dependent upon the genetic makeup of the host. In a recent study, it was shown that sheep intracerebrally inoculated with a US scrapie agent (No. 13-7) developed scrapie and survived for an average of 19 months post inoculation. In the present study, when this scrapie inoculum was further passaged for 3 successive generations, the survival time was reduced by approximately 8 months in scrapie-susceptible (QQ on prion protein gene [PRNP] at codon 171) Suffolk sheep. It is concluded that inoculum No. 13-7 appears to have been stabilized in susceptible (171 QQ) Suffolk sheep and may be considered a specific isolate of sheep scrapie agent in the USA and therefore that it can be used to evaluate other isolates of sheep scrapie in this country.
Hamir
A N
AN
National Animal Disease Center, ARS, USDA, Ames, IA 50010, USA. amir.hamir@ars.usda.gov
Kunkle
R A
RA
Richt
J A
JA
Greenlee
J J
JJ
Miller
J M
JM
D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D007150:Immunohistochemistry / Q000662:veterinary; D011328:Prions / Q000235:genetics*; D012608:Scrapie / Q000235:genetics*; D012692:Serial Passage / Q000662:veterinary*; D012756:Sheep; D016019:Survival Analysis
D011328:Prions