Project 1503: CWD Test & Cull Study

A promising project with a 2016 start date plans to help illustrate alternative solutions for managing CWD positive herds. The current approach for many states and provinces when handling a case of CWD in a captive herd is to quarantine and ultimately depopulate the entire herd. In some areas, specific management plans are developed while the herd remains under quarantine to keep the post-mortem prevalence of CWD on a premise site to a minimum.

ERC Project 1503 offers at two phase study:

The first phase is analyzing ante-mortem samples - including blood, saliva, lymph node aspirates and rectal biopsies - from a group of captive elk. The results of the analyses can be compared with alternative testing methods.
The second phase includes the Management of CWD in an endemic herd through antemortem testing, directed culling, and genetic screening and development of resistant breeding program. The study will use the most sensitive antemortem sample available to test a large cervid herd with a history of high CWD prevalence over 5 years. All animals will be genotyped for species-specific resistance markers (e.g. 132L alleles in elk). Animals positive by antemortem testing will be managed using appropriate methods as determined by the herd owner (targeted hunting, out of season culling, etc.). In subsequent years, antemortem testing will be performed as the opportunity arises, with management proceeding as in the initial testing year. New animals, e.g. calves or imported animals, will be genotyped when yearly CWD sampling is performed or prior to introduction, to monitor the frequency of resistant alleles and assure introduction of resistant animals. In the absence of antemortem testing, management directives will be targeted at highly susceptible animals to decrease the frequency of susceptible alleles in the herd.

"This project is very important in showing what we hope to be a new precedent that can be set", said Executive Director Travis Lowe. "The current management style practiced in most states and provinces is a death penalty for producers. The USDA's Federal CWD Rule is intended as a control based program. Scorched earth policies are counterproductive in our quest to grow the industry."

The Elk Research Council partnered with Midwestern University on this project.

Journal Publication: Chronic wasting disease management in ranched elk using rectal biopsy testing