Editor’s Note: this is the third of eight bi-weekly columns in which the Department of Natural Resources Secretary will try to answer some of the many questions and concerns related to Chronic Wasting Disease (CWD) in Wisconsin
Where will DNR test wild deer for CWD this fall and how many will be tested?
We will be testing between 15,000 and 20,000 wild deer from selected counties this year, the majority of which will be in the Herd Reduction (HRZ), Intensive Harvest (IHZ) and Disease Eradication (DEZ) Zones of southern Wisconsin.
Testing guidelines are as follows:
IHZ/DEZ – We will test any deer being kept by a hunter if requested. We will test all adult deer whose carcasses are turned over to DNR for disposal. We are particularly interested in testing adult deer from the higher prevalence ‘core area’ of western Dane-eastern Iowa Counties to help increase our understanding of CWD and measure the success of our CWD control efforts. We will not test fawns, unless requested by the hunter. Sampling will take place during the entire deer-hunting season running from Sept. 13 through Jan. 3. Hunters who wish to have their deer tested or for disposal must bring animals to one of the following deer registration sites:
Heck’s Farm Market, 7266 STH 14, Arena
Eagle Mart Stop-N-Go, 8029 STH 151, Barneveld
Norslein’s Wood Works, 4738 STH 87, Black Earth Lower Wisconsin State Riverway, Lone Rock Unit, one mile west of Lone Rock on STH 14
In addition, hunters who plan to keep their deer but are not interested in having the deer tested may register deer from Sept. 13 through Jan. 3 at the following sites:
Bootlegger’s, 545 N. Main, Highland Ace Hardware, 500 Water St., Sauk City
Muscoda Mini-Mart, 102 N. Wisconsin Ave., Muscoda
I-Diehl Tap, 400 Main St., Plain HRZ – Adult deer will be sampled during the early CWD season (Oct. 30 – Nov. 2) and the opening weekend of the traditional gun deer season (Nov. 22-23). Sampling locations will be publicized prior to the opening of the early CWD season.
Out-State – Adult deer will be tested in counties where not enough samples were obtained last fall and from areas where captive deer or elk have tested positive for CWD. Most of the sampling will occur over the traditional gun deer season’s opening weekend. Again, we will publicize sampling locations prior to the nine-day season.
Is anybody working on a live animal test?
One live animal test for CWD has already been developed by researchers with the Colorado Division of Wildlife. This test involves a biopsy (examination) of a tonsil from the throat of an anesthetized deer. It is both expensive and labor intensive. Blood test research has garnered some media attention, but it appears that a breakthrough isn’t near. Researchers at the University of Wisconsin’s Veterinary Diagnostic Laboratory (WVDL) are studying the lymph nodes that lie under the skin to evaluate if they could be used to identify CWD in deer. If peripheral lymph nodes consistently indicate the animal’s CWD status (positive or negative), then biopsy and testing of these tissues may be possible on live, captive deer.
Is anyone in Wisconsin working on a quicker test for CWD?
WVDL is working with six companies who have developed alternative CWD testing systems which can be used as an initial screening test rather than the “gold standard” immunohistochemistry (IHC) test Wisconsin used last fall.
WVDL is presently assessing each of these alternative systems in order to determine their accuracy, number of samples that could be processed daily, and cost as compared to the IHC test for initial screening of deer for CWD. This assessment should be completed soon and WVDL will choose a screening test for 2003 surveillance of wild deer based on these results.
This year, with WVDL using one of these “quicker” tests and because we will be sampling half as many deer as last year, test results will be available much sooner than in 2002. Most hunters can expect results within several weeks of sampling.
How are tissues from animals that tested positive last year being used?
DNR, responding to our state’s need for more information on CWD and the scientific community’s increased research efforts, is sharing wild white-tailed deer tissues collected during statewide CWD surveillance with researchers both here in Wisconsin and nationwide. By sharing tissues with researchers, more will be learned about CWD ecology and management, and improvements will be made in CWD testing accuracy and efficiency.
A subcommittee of the Interagency CWD Health and Science Team, comprised of representatives from the state Departments of Agriculture, Trade and Consumer Protection, Health and Family Services, the University of Wisconsin, WVDL and DNR, reviews requests for CWD deer tissues every six months.
To date, shared tissues have been used to validate and compare alternative tests to detect CWD prion in deer, to study the disease-causing prion, to investigate possible human health risks through primate exposure studies, and to evaluate the persistence of prions in the environment. Tissues have also been used for genetic research, including a recently completed study by UW-Madison that indicated the vast majority of Wisconsin white-tailed deer are genetically susceptible to CWD.
All research results using Wisconsin tissues will be shared with DNR. CWD management efforts will be adapted based on this accumulating science. We must be willing to learn more as new scientific information becomes available and adjust our disease eradication strategies accordingly in order to be most effective at eliminating CWD from Wisconsin. This is part of our “learn and adapt” approach to CWD management in Wisconsin.
What about the recently identified CWD positive deer in Walworth County.
A three-year-old female deer shot by a police officer in the Village of Fontana tested positive for CWD. The site of the kill is about two miles outside of the Herd Reduction Zone (HRZ). While this discovery was not predicted, we consider Walworth County’s deer population to be at higher risk for having CWD.
That’s because the CWD has been confirmed in wild deer in two areas about 20 miles south of Fontana in the northern Illinois counties of Boone, McHenry and Winnebago. Fourteen wild deer have tested positive between these three Illinois counties that border Wisconsin.
There are also two deer farms in Walworth County that have been quarantined for CWD, one of which had a confirmed CWD-positive deer.
We don’t know how this Fontana CWD positive deer became infected, but we will learn as much as we can from this deer and from more intensive surveillance this fall. Based on what we learn about the distribution and severity of CWD in Walworth County, we will then decide on our next management steps.
We are grateful that this sick-looking deer was noticed by a member of the Fontana community and reported to DNR. We will continue to rely on folks from southern and southwest Wisconsin to give a local wildlife biologist or conservation warden a call about any sick-looking deer they may see. We want to test all animals from anywhere in the state that fit the profile for a possible CWD infected deer. This includes any adult deer that is very skinny and exhibits abnormal behavior such as little fear of people, disorientation, wobbliness, or other signs of nervous system disease.