' ' jHH 



~i 



1 j 



1 1 r 





"^msB^SSS^ 



~ I - 



1 ■ ' i ■ 



^^ 





m 



1 



' 









r 



t ^ ■ 



;^ig^^^«BH| 



s^ 



'^'^'^mm \ 



■■■V^:./^' 



^p'-" 



..'I^^^^^BK 



1 





P-'' , IP 



t..^.::: 



WL^ wi 



i 





1 



- 



HHwn| 



^ 









H^m 



r J 



te^-J- 



^-^^ 





^ '9HE 



r 



. , "/I 







W -1 < 



B 



; *^ 



A deer walks through a "filming lane" — part of a new species- 

 recognition software and camera system used to regulate 

 animal access to baits or other resources. 



Wildlife and CSU, and support from WS, scientists 

 have already accumulated important efficacy data 

 on the CWD vaccine. 



Currently, prime and booster injections of the 

 vaccine have been administered to mule deer 

 housed at CSU's Animal Population Health 

 Institute paddocks, a CWD-free environment. The 

 experimental animals were subsequently transferred 

 to the Colorado Division of Wildlife's CWD-infected 

 paddocks at the Foothills Wildlife Research Facility 

 in Fort Collins. 



have initiated a collaborative study with these 

 organizations to acquire video imagery of domestic 

 and wildlife species required to adapt and test the 

 prototype system for use in North America. Primary 

 efforts have focused on cervids susceptible to CWD 

 and on other domestic and wildlife species similar 

 in body type to cervids that may "confuse" the 

 computer system. 



NWRC scientists acquired the prototype camera 

 system and species recognition software in 2007 

 and have fabricated a filming lane similar to that 

 used by Australian researchers. The filming lane 

 is designed to encourage single-file passage of 

 large animals to facilitate the clear lateral imagery 

 required for species identification. To date (October 

 2007), the trial has resulted in high-quality imagery 

 of 15 elk, 13 mule deer, and 15 white-tailed deer. 

 The trials continued throughout 2007 so that 

 scientists can evaluate the accuracy of the species 

 recognition software and its potential uses. 



CWD Vaccine— NWRC research into a CWD 

 vaccine continues to move forward along several 

 fronts. An experimental vaccine trial in the widely 

 used RML mouse scrapie model system yielded 

 two promising candidates for further study. 

 Currently, the two CWD vaccine candidates have 

 been resynthesized, formulated, and used to 

 vaccinate mule deer, making this the first known 

 application of a CWD vaccine in the target species. 

 This pivotal CWD vaccine study is a model of 

 cooperation between State and Federal agencies. 

 With guidance from USDA-APHIS' Veterinary 

 Services, collaboration with the Colorado Division of 



Preliminary results show that the mule deer are 

 producing good antibody titers to peptides 4 and 

 6 in response to the vaccine. Data also show that 

 these antibodies have high affinity to the prion. 

 The deer have already passed more than 120 days 

 since their disease challenge in an environment 

 that simulates natural CWD transmission routes. 

 Conclusive results on how well the CWD vaccine 

 works in mule deer will not be known for another 

 year to 18 months. Additional vaccine work using 

 a mouse model is being initiated, including the 

 design of an oral CWD vaccine. 



Testing of Hydrolysis and Rendering Effects on 

 Prion Infectivity — Infectious prions are inherently 

 resistant to destruction. With support from the beef 

 industry, NWRC biologists are testing how effective 

 hydrolysis and rendering procedures are at destroying 

 infectious prion material to determine if these 

 methods are viable carcass waste-disposal options. 



Hydrolysis is a process of using lye under increased 

 pressure and temperature to degrade biological 

 material. Proteins are broken down into component 

 amino acids during the process. Rendering is a 

 process of cooking material in oil. NWRC biologists 

 are testing the effects of hydrolysis and rendering 

 using a mouse model of prion disease with infected 

 mouse brain as the test material. Following 

 hydrolysis and rendering, the material was injected 

 into test mice. 



Six months after inoculation, some of the mice 

 are showing signs of developing the disease. 

 Preliminary results showed none of the 23 mice 



Developing Methods 21 



