Greetings WV hunters,
It seems that five Additional Deer Test Positive for Chronic Wasting Disease In Hampshire County, West Virginia Preliminary test results indicate the Chronic Wasting Disease (CWD) agent was present in five hunter-harvested deer collected in Hampshire County during the 2008 deer firearms hunting season.
North American Cervids Harbor Two Distinct CWD Strains
Angers, R. Seward, T, Napier, D., Browning, S., Miller, M., Balachandran A., McKenzie, D., Hoover, E., Telling, G. 'University of Kentucky; Colorado Division of Wildlife, Canadian Food Inspection Agency; University Of Wisconsin; Colorado State University.
Despite the increasing geographic distribution and host range of CWD, little is known about the prion strain(s) responsible for distinct outbreaks of the disease. To address this we inoculated CWD-susceptible Tg(CerPrP)1536+/· mice with 29 individual prion samples from various geographic locations in North America. Upon serial passage, intrastudy incubation periods consistently diverged and clustered into two main groups with means around 210 and 290 days, with corresponding differences in neuropathology. Prion strain designations were utilized to distinguish between the two groups: Type I CWD mice succumbed to disease in the 200 day range and displayed a symmetrical pattern of vacuolation and PrPSc deposition, whereas Type II CWD mice succumbed to disease near 300 days and displayed a strikingly different pattern characterized by large local accumulations of florid plaques distributed asymmetrically. Type II CWD bears a striking resemblance to unstable parental scrapie strains such as 87A which give rise to stable, short incubation period strains such as ME7 under certain passage conditions. In agreement, the only groups of CWD-inoculated mice with unwavering incubation periods were those with Type I CWD. Additionally, following endpoint titration of a CWD sample, Type I CWD could be recovered only at the lowest dilution tested (10-1), whereas Type II CWD was detected in mice inoculated with all dilutions resulting in disease. Although strain properties are believed to be encoded in the tertiary structure of the infectious prion protein, we found no biochemical differences between Type I and Type II CWD. Our data confirm the co·existence of two distinct prion strains in CWD-infected cervids and suggest that Type II CWD is the parent strain of Type I CWD.
see page 29, and see other CWD studies ;
Sunday, November 23, 2008
PRION October 8th - 10th 2008 Book of Abstracts
Saturday, September 06, 2008 Chronic wasting disease in a Wisconsin white-tailed deer farm 79% INFECTION RATE Contents: September 1 2008, Volume 20, Issue 5
snip...see full text ;
Wednesday, December 17, 2008 White-tailed Deer in Portage County Tests Positive for CWD