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Date: Tue, 29 Oct 2002
Posted by: ERAP (envrisk@cornell.edu)

[The following posting is forwarded from Tom Scheib (tascheib@lakeland.ws), sent to the Environmental Risk Analysis Program]

Report to the Captive Wildlife and Alternative Livestock and Wildlife Diseases committees
Wed, 23 Oct., 2002 at USAHA meeting in St. Louis, Mo.

My name is Tom Scheib. I am Vice President of the 200-member Reindeer Owners and Breeders Association {ROBA}. I raise reindeer in Milltown WI and Taylor's Falls MN.

ROBA members have been speaking with veterinarians and wildlife biologists in various agency positions regarding WNV and the possible effects to their reindeer and herds since 1999. The overwhelming response from that community was reindeer should not be expected to contract WNV.

On September 6 and 7 of this year I experienced the sudden deaths of two[2], 5 month old reindeer calves in excellent condition at my leased farm in Taylor's Falls MN. The first calf, a heifer, was sent to the WI diagnostic lab at Barron WI, about 40 miles away. The animal was not tested for WNV and cause of death was not definitively determined. The second death, a male, was early the next morning, a Saturday. A necropsy was done by my vet [Dr John Springer] in high temp and humidity with samples sent to Barron on Monday. The cause of death was not definitively determined. The animal was not tested for WNV.

About a week later, on Sept 12th in late afternoon, I observed a 10 1/2 yr old reindeer bull on my farm at Milltown WI in an apparently weakened condition with ears down and at times staggering. That Wi farm is about 7-8 miles from the MN farm, across the St Croix River, the border between the 2 states. His condition did not improve overnight, he went down about 5 am on the 13th, was in rut, and was euthanized a few hours later. He was sent, intact, to the Barron lab. He was not tested for WNV. The brain stem was sent to NVSL for CWD testing, as required by WI rules.

When the reindeer bull was euthanized we suspected brainworm may have been a possible cause of the symptoms, after all, cervids/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.

Later on that same day, Friday, the 13th of Sep, I observed a 12 1/2 year old gelding reindeer that was in the same pen as the euthanized bull exhibiting similar symptoms. Since he could still walk, he was led to a large trailer for confinement and treatment for brainworm. He was kept alive for 10 days with supportive treatment, ampicillian, Ivomec, banamine, Vitamin B complex, and dexamethazone. After 3 days of treatment he appeared to improve, and continued to eat and drink, but then began to fail as paralysis continued to progress.

During the treatment period we began to suspect WNV. He died on Sunday, 22 Sep. I had previously decided, since he and I had been constant companions for more than a dozen years, that he would not be carted off in a rendering truck from the lab but would be buried on the farm, in the pen in which he had lived.

The brain, as required, and blood samples were delivered to the Barron Lab the next day, Monday, for further transfer to NVSL. The gelding was sero and PCR positive for WNV.

On October 1st, I was informed by Dr Mitch Palmer 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. However, to date, clinical signs have only been seen in the reindeer. Those 3 deaths occurred on Sep 20, 24 and 27.

1. Two were found febrile, in lateral recumbency with tetraplegia (all 4 limbs paralyzed).

2. A third was febrile, depressed, head tilt, flaccid tongue with dysphagia (difficult swallowing), progressing to tetraplegia within 12 hours.

3. Brains were PCR positive at NVSL.

4. Histology- mild lymphocytic perivascular cuffing and edema, gliosis and lymphocytic infiltrates. Lesions most pronounced in medulla although still categorized as mild to moderate. Spinal cord also contained perivascular lymphocytic cuffing and marked myelin sheath swelling. Myocardium contained mild multifocal areas of myofiber degeneration/necrosis with little inflammation.

5. WNV IHC showed mild staining limited to the brain stem and spinal cord.

6. CBC's on the Sep 24 and Sep 27 deaths indicated elevated fibrinogen, stress leukogram, and lymphopenia- consistent with a viral infection.

Some ROBA members have observed similar symptoms in reindeer that have died this past summer, and earlier, but were not tested for WNV.

Many, if not most of our herds are in mandatory or voluntary CWD monitoring programs requiring the brain stem of adult animals for CWD testing. That tissue is also, as I understand, the tissue of choice for WNV testing, a dilemma for the reindeer owner whose species is one of 34 that has yet to exhibit CWD but appears very susceptible to WNV, while other cervids may not be.

A review of the federal response time for our Tb testing problems can be used to point out the difficulties our industry has suffered through previously. There is no reason to repeat this scenario. We believe USDA APHIS can ensure the appropriate pathologists are aware of the reindeer susceptibility to WNV when examining brain stems for CWD. This may have already been accomplished.

Any assistance by USDA or other agencies in developing, recommending and testing an appropriate vaccine for reindeer for WNV would be greatly appreciated.

Thank you. Tom Scheib, Reindeer Owners and Breeders Association

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