The Dallas Safari Club is advocating for non-lethal live testing for CWD, hoping to avoid a repeat of the destruction of deer in breeding facilities across Texas earlier this summer.
The Dallas Safari Club (DSC) issued a statement in which it acknowledged the need for testing cervids for chronic wasting disease (CWD). But the organization was also guardedly critical of the Texas Parks and Wildlife Department decision to euthanize large numbers of deer from breeding facilities where the presence of CWD is suspected.
DSC asserts that live tests for CWD should be employed in order to avoid destroying large numbers of healthy deer.
Currently, post-mortem testing of brain tissue is the only form of CWD testing approved by the USDA even though an effective, non-lethal alternative test exists.
The presence of CWD in Texas was first reported in 2012. It was detected in a free-range mule deer in west Texas. The discovery sparked concern for hunting and conservation groups throughout Texas.
That concern grew to alarm earlier this summer with the confirmation of CWD found in a captive whitetail deer in Medina County.
There are over 1,300 captive deer breeding operations in Texas, holding a total of around 110,000 deer. Such breeding facilities are thought to be particularly conducive to spreading CWD, which may transfer from captive deer to deer in the wild.
The uncontrolled spread of CWD – an always fatal disease – in both captive and wild cervids could be devastating to the state.
Texas has around four million free-ranging deer, which attract more than 700,000 deer hunters each year. The deer hunting season provides a significant source of revenue to the state and rural landowners.
PR Newswire indicates that “deer hunting in Texas represents $2.1 billion in economic impact, derived from license fees, excise taxes, funds raised by hunting and conservation groups, and hunters’ spending. All of this is in addition to the indirect financial impacts that healthy and huntable wildlife populations have on real estate and other rural values.”
The discovery of the infected deer in Medina County and resulting alarm compelled a number of hunting/conservation organizations and scientists to draft a resolution supporting firm and decisive action from the state in initiating protocols to identify and address the threat of CWD.
Signers to the resolution include the Texas Wildlife Association, Texas Chapter of The Wildlife Society, Boone & Crockett Club, Borderlands Research Institute, Caesar Kleberg Wildlife Research Institute, Texas Wildlife and Fisheries Management Council and several individual wildlife scientists.
DSC supports decisive action concerning the issue of CWD as well, but is also advocating for live testing of captive deer for CWD.
They state, “A results of a study of rectal mucosa testing for CWD in white-tailed deer published by the USDA’s National Veterinary Research Laboratories in Ames, Iowa, shows extremely high diagnostic accuracy, one which could eliminate the need to destroy herds simply suspected to have been exposed to the disease.”
The approval and implementation of a live-test protocol could, they argue, eliminate the need for the destruction of large numbers captive deer and, by extension, the adverse economic impact to the hundreds of captive deer facilities affected by current post-mortem-only testing.
DSC Executive Director Ben Carter is quoted in the statement;
Private hunting operations and land-leasing programs, including those utilizing deer from licensed and scientifically managed breeding herds, contribute vast resources to habitat restoration and development in Texas. These resources benefit game and non-game species alike. We support the rights of Texas landowners to continue to manage their properties in such a way that continues to enhance habitat quality and boost the populations of game and non-game species. We encourage landowners to continue to be fine stewards of their land and to continue working alongside the TPWD and the Texas Animal Health Commission to ensure all measures are taken to prevent this from happening again.
Our sympathy goes out to the owners of the breeding facilities whose deer were destroyed. The euthanizing of these animals was unpleasant and DSC supports testing as a means to protect the state’s deer population. At the same time, we hope the destruction and post-mortem testing of these animals will hasten the adoption of a live test for CWD.
Dr. Roel Lopez, President of the Texas Chapter of The Wildlife Society, summarized the issue at a July 16 Texas Parks and Wildlife Commission special meeting.
“The actions and measures implemented in the next few months will serve to shape the future of our native deer populations for generations to come. We are at a critical crossroad, and how we move forward should not be short sighted.”
Scientific studies of the effectiveness of the rectal-mucosa live-test confirm that its accuracy is somewhat lower than post-mortem testing in detecting CWD. But it does have advantages in cost, efficiency and the fact that large numbers of animals do not have to be euthanized in order to conduct the test.
Concerning the live-test procedure, the Journal of Clinical Microbiology concludes:
On the basis of the results of our study…RAMALTs [rectal-mucosa live-testing] should be considered a useful tool for the preclinical diagnosis of CWD in white-tailed deer.
The RLN [post-mortem testing] is the most sensitive indicator of CWD but is suitable for use only for analysis by necropsy. Because the sensitivity of the PrPCWD IHC assay with RAMALTs does not appear to be as high as it is with tonsil tissues, the use of RAMALT biopsy specimens may not be as reliable a tool as the use of tonsil biopsy specimens for the testing of individual animals for the purpose of movement. However, the advantages of cost and ease of sampling make testing of RAMALTs a reasonable alternative in situations in which large numbers of live white-tailed deer are to be tested. This study further supports the use of RAMALTs as an alternative or adjunct to tonsil biopsy specimens, particularly for farmed deer with potential environmental exposure or exposure to cervids with CWD.
It would seem that the implementation of live-testing for CWD, as advocated by Dallas Safari Club would be a sensible part of the measures employed in combatting CWD.
It begs the question of what exactly is preventing the live-testing procedure from being approved and implemented?