- Hello, Jeff - Yes, I know, it was believed that reindeer
could NOT contract WNV. Think again. Due to the fact that Reindeer have
now been found to have contracted WNV, distinguishing between Chronic Wasting
Disease and West Nile Virus will be difficult, therefore tests for both
diseases will be required.
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- Minnesota Reindeer Die From WNV
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- A ProMED-mail post http://www.promedmail.org ProMED-mail
is a program of the International Society for Infectious Diseases http://www.isid.org
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- By Sylvia Macbean s.macbean@sasktel.net The Deer Farmers'
Digest, Nov 2002 [edited] www.deer-digest.com
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- By Tom Scheib, vice president of the Reindeer Owners
and Breeders Association (ROBA) with reindeer farms in Milltown WI and
Taylor's Falls MN.
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- Reindeer owners have frequently heard that "cervids
are cervids" or "deer are deer." From anecdotal experience,
we believe that reindeer respond differently than many other cervids to
various disease and testing situations. Presentations during annual USAHA
meetings have demonstrated these experiences are being validated by scientific
studies.
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- At the 2001 Captive Wildlife and Alternative Livestock
committee meeting, Dr Tracey McNamara commented on cases of West Nile virus
(WNV) infection, showing that initial assumptions of the disease and its
effects were wrong. ROBA members have been speaking with veterinarians
and wildlife biologists in various agency positions since 1999 regarding
WNV and the possible effects to their reindeer and herds. The overwhelming
response from that community was reindeer should not be expected to contract
WNV.
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- The author [named above] lost 2 young reindeer to what
was at the time believed to be chronic wasting disease (CWD). These animals
were not tested for WNV. Neither of these animals had a definitive diagnosis
determined. Very shortly after the loss of these animals, the author observed
his 10 year old reindeer bull exhibiting an apparently weakened condition
with ears down and at times staggering. The bull's condition did not improve
overnight and he was euthanized some time that morning. He was sent, intact,
to the Barron lab. He was not tested for WNV. The brain stem was sent to
NVSL (National Veterinary Services Laboartory) for CWD testing, as required
by Wisconsin rules. When the reindeer bull was euthanized, brainworm was
suspected as a possible cause of the clinical signs observed. Cervids and
reindeer were not expected to contract or exhibit symptoms of WNV. CWD
testing subsequently indicated that no prions were evident. The cause of
death was not definitively determined.
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- On the same day the author observed his reindeer bull's
clinical signs, a 12 year old gelding reindeer began exhibiting very similar
signs. This animal was confined and treated for brainworm. This animal
was kept alive for 10 days with supportive treatment, ampicillin, Ivomec,
banamine, vitamin B complex, and dexamethasone. After 3 days of treatment
the animal appeared to improve, and continued to eat and drink, but then
deteriorated and developed paralysis. During the treatment period WNV became
a suspected cause of the animal's demise. The brain, as required, and blood
samples were delivered to the Barron Lab the next day, for further transfer
to NVSL. The gelding was sero and PCR (polymerase chain reaction) positive
for WNV.
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- On October 1st, I was informed by Dr Mitch Palmer [who
he? - Mod.SH] that 3 of the 19 reindeer delivered to NVSL in May had died
of WNV. Those reindeer, housed at NADC, are on pastures adjacent to or
near pastures containing elk, white-tailed deer, bison, cattle, sheep,
and horses. To date, however, clinical signs have been seen only in the
reindeer and 3 have died -- on 20, 24, and 27 September 2002.
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- Two of the dead reindeer were found febrile, in lateral
recumbency with tetraplegia (all 4 limbs paralyzed). A third was febrile,
depressed, head tilt, flaccid tongue with dysphagia (difficult swallowing),
progressing to tetraplegia within 12 hours. Their brains were PCR positive
at NVSL. Histological examination showed mild lymphocytic perivascular
cuffing and edema, gliosis, and lymphocytic infiltrates. Lesions were most
pronounced in medulla, but still categorized as mild to moderate. The spinal
cord also contained perivascular lymphocytic cuffing and marked myelin
sheath swelling. The myocardium contained mild multifocal areas of myofiber
degeneration/necrosis with little inflammation. WNV immunohistochemistry
showed mild staining limited to the brain stem and spinal cord. Complete
blood counts on the September 24 and 27 deaths indicated elevated fibrinogen,
stress leukogram, and lymphopenia -- consistent with a viral infection.
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- Some ROBA members have observed similar symptoms in reindeer
having died this past summer and earlier, but were not tested for WNV.
The voluntary CWD monitoring programs requires the brain stem of deceased
adult animals for CWD testing. That tissue is also the tissue of choice
for WNV testing. This is a dilemma for the reindeer owner whose species
is 1 of 34 that has yet to exhibit CWD but appears very susceptible to
WNV, while other cervids may not be.
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- The reindeer industry suffered because appropriate people
were unaware that tuberculosis occurred in reindeer. There is no reason
to repeat this scenario. The United States Department of Agriculture Animal
and Plant Health Investigation Service can ensure the appropriate pathologists
are aware of reindeer susceptibility to WNV when examining brain stems
for CWD. ROBA appeals for any assistance from USDA or other agencies in
developing, recommending, and testing an appropriate vaccine for reindeer
for WNV. ___
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- ProMED-mail promed@promedmail.org
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- The similarity between WNV and CWD in reindeer is disturbing
and confusing. It is essential that pathologists recognize the possibility
that reindeer may have WNV as well as/rather than CWD. It also brings up
the question as to whether some of the other sick cervids in Wisconsin
and other areas may also have WNV. - Mod.TG
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- Patricia A. Doyle, PhD Please visit my "Emerging
Diseases" message board at: http://www.clickitnews.com/emergingdiseases/index.shtml
Zhan le Devlesa tai sastimasa Go with God and in Good Health
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