The C.A.S.H. Courier Newsletter
Spring 2012 Issue
Deer – Why No Live Testing for CWD?
By E.M Fay
Photo by Dr. Elizabeth Williams, University of
Wyoming
Photo from Colorado DOW
Chronic Wasting Disease is a very
real problem in North America, both in Canada and the United States. A
transmissible spongiform encephalopathy (TSE), it is a progressive, fatal,
degenerative disease affecting elk, white-tailed deer, mule deer, and moose.
CWD is manifested as brain damage, loss of body condition, behavioral
changes, excessive salivation, and death.
Caused by abnormal
proteins, called prions, which accumulate in the brain, the disease spreads
from one animal to another and females can pass it to their young. A
probable route is through contaminated water and food via animal saliva and
feces. Contagion is more likely when the animals are in crowded situations
and when they congregate at man-made feed and water stations.
Although CWD has been found in both wild and captive cervids, there has
been no evidence of possible transmission to domestic animals or livestock.
There is also none showing CWD affecting humans, but the World Health
Organization advises against eating meat from affected animals:
http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex3594
As
CWD has been documented in at least 19 states, Departments of Natural
Resources have been testing many animals for the disease. It is
illegal to import deer from one state to another, but of course deer do not
know about crossing state boundaries; and also, some humans who keep captive
deer or elk for personal or commercial purposes, such as “canned” hunts or
for slaughter, do not follow the rules. The fear of CWD spreading to
new states has led to some private properties being invaded by DNR personnel
to carry out testing on captive animals. Unfortunately, this testing
is done only after killing them.
In one example, in September, armed
wildlife agents from the North Carolina Wildlife Commission brought a
warrant to a farm in Asheboro, Randolph County. They killed nine deer
there, seven of which were exotic fallow deer; the other two were
white-tailed deer who were being rehabilitated either from injury or being
orphaned.
The farm owner, Mr. Wayne Kinley, had not been notified
ahead of time, and there was no appeal process available to him. The deer
had been living peacefully in a two-acre enclosure on the farm.
In
August, wildlife agents similarly invaded another North Carolina property
and shot and killed 2 orphaned fawns. The property owner, Freddy Snow of
Dobson, was not even at home when they were killed. Officials said
that neither Kinley nor Dobson had a license to keep captive deer.
Although the agents stated that these deer were killed to test for Chronic
Wasting Disease, CWD has not yet been found to be present in North Carolina.
Kinley stated that the killing was done with 12-gauge shotguns, which is
considered by some to be a less “humane” method than shooting with a rifle.
And wildlife officials admitted afterwards that none of the deer tested
positive for the disease.
Change.org circulated an online petition,
asking citizens to demand that the governor of NC provide protection for
tame or rehabilitated deer. (The petition was created by Millie
Bowling of Liberty, NC.)
I spoke with Gordon Myers, Executive Director of
the North Carolina Wildlife Resources Commission. He justified the kills for
these reasons: You can’t tell if a deer has been imported from another
state; if it has been, then there is a chance of CWD. The fallow deer were
illegally imported, he said. He believed that the owner was using them
to make chandeliers from their antlers. (We tried to ask the owner to
confirm or deny this allegation, but could not reach him.)
Myers also
noted that there has been a big increase in cases of CWD since 2002, and
they test for safety’s sake, so out-of-state deer do not communicate it to
the local deer population.
When I asked what about the orphaned fawns,
who were local, according to the rehabber, Myers said they cannot be sure of
that.
Why kill the deer first, instead of testing for CWD on live deer?
Myers replied that the only practical method is testing brain tissue or
lymph nodes, which has to be done after death. We checked this
statement with two other sources: a Wildlife Technician in Wisconsin, a
state that has seen many cases of CWD in recent years; and a Senior Staff
Veterinarian and CWD Program Manager for APHIS (Animal and Plant Health
Inspection Service).
The Wisconsin Wildlife Technician told us that
there is a live tonsil biopsy test but it is not approved for use by the DNR
in Wisconsin. He said it is used mainly for research purposes.
The
CWD Program Manager told us that while tonsils may be collected from live
animals, the sampling data collected by the national reference testing
laboratory over approximately 10 years has shown that collection of tonsil
samples is not very reliable. “Most often the proper sample (the
tonsil) is not correctly collected because it is difficult to reach and
visualize the tonsillar tissue located far back in the animal’s throat while
the animal has been anesthetized for this procedure,” she said. “Therefore,
many times the sample submitted as ‘tonsil’ is found in the laboratory
testing process to be an adjacent section of soft tissue oral mucosa - and
not suitable for CWD testing.”
According to the Chronic Wasting Disease
Alliance, however, researchers from the USDA and Colorado State University
have evaluated and validated another live testing method using rectal-tissue
biopsies in captive and wild elk in Colorado. It appears to be nearly
as accurate as post-mortem testing.
“The key advantage to the rectal
biopsy test is that it can be performed on live animals. Until now, there
was no practical live test for CWD in elk,” said Research Wildlife Biologist
Dr. Kurt Ver Cauteren with APHIS’ Wildlife Services.
“The use of
this new live test in the initial screening, surveillance and monitoring of
CWD will greatly aid in the management and control of the disease in the
wild, as well as in captive settings,” said Ver Cauteren.
Chronic Wasting
Disease Alliance reports that many thousands of captive elk have been killed
in the western United States and Canada in order to control CWD, as well as
thousands of free-ranging mule deer, white-tailed deer, and elk.
(Learn more about CWDA’s work at: www.cwd-info.org )
As congested areas
with man-made feed and water stations – e.g., on “deer farms” with animals
kept prisoners in a limited space – are more likely to encourage the spread
of CWD than when deer and elk live in wide-open, natural habitats, it is not
unreasonable to posit the theory that humans have facilitated the spread of
CWD by keeping these wild animals in unnatural circumstances. This would be
not unlike the phenomenon of BSE, or “mad cow disease,” which even the CDC
acknowledged could have been caused by farmers feeding unnatural foods such
as meat and bone meal to herbivorous cattle.
While we at
C.A.S.H. are in favor of the development of a live testing method, we could
wish that the motives behind such studies were concern for the health and
welfare of the animals themselves. However, motivation seems to be at
least partly on behalf of the captive deer and elk “industry.”
The
promising progress shown in finding a new live testing method should be
encouraged, with government funds channeled in that direction, rather than
spent on continuing the inhumane post-mortem test that leads to “shoot
first, ask questions later,” as is currently being practiced.
CWD information at:
http://www.aphis.usda.gov/animal_health/animal_diseases/cwd/
http://www.health.ny.gov/diseases/communicable/zoonoses/cwd.htm
--------------------------
E.M. FAY is the Associate Editor of the
C.A.S.H. Courier
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Don't Allow Your Town to Participate in a
Bait and Shoot Program
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