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From: TSS (216-119-144-68.ipset24.wt.net)
Subject: Re: SPONGIFORM ENCEPHALOPATHY ADVISORY COMMITTEE Draft minutes of the open session of the 84th meeting held on 28th September 2004
Date: October 22, 2004 at 2:38 pm PST

In Reply to: Re: SPONGIFORM ENCEPHALOPATHY ADVISORY COMMITTEE Draft minutes of the open session of the 84th meeting held on 28th September 2004 posted by TSS on October 22, 2004 at 2:32 pm:


-------- Original Message --------
Subject: Re: CWD TO CATTLE by inoculation (ok, is it three or four OR NOW FIVE???)
Date: Mon, 23 Jun 2003 09:25:27 -0500
From: "Terry S. Singeltary Sr."
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@uni-karlsruhe.de

######## Bovine Spongiform Encephalopathy #########

Greetings List Members,

i hear now that a 5th cow has gone done with CWD from the
studies of Amir Hamir et al. will Dr. Miller please
confirm or deny this please, and possibly explain why
this has not made the news, if in fact this is the case?

seems these cows infected with CWD/TSE did not display the
usual BSE symptoms. i wonder how many more are out there
in the field? course, we will never know unless someone
starts rapid TSE/BSE testing in sufficient numbers to find...

thank you,
kind regards,
terry


Date: Sat, 23 Nov 2002 18:54:49 -0600
Reply-To: BSE
Sender: BSE
From: "Terry S. Singeltary Sr." Subject: CWD TO CATTLE by inoculation (ok, is it three or four???)
1: J Vet Diagn Invest 2001 Jan;13(1):91-6

Preliminary findings on the experimental transmission of chronic wasting
disease agent of mule deer to cattle.

Hamir AN, Cutlip RC, Miller JM, Williams ES, Stack MJ, Miller MW,
O'Rourke KI, Chaplin MJ.

National Animal Disease Center, ARS, USDA, Ames, IA 50010, USA.

To determine the transmissibility of chronic wasting disease (CWD) to
cattle and to provide information about clinical course, lesions, and
suitability of currently used diagnostic procedures for detection of CWD
in cattle, 13 calves were inoculated intracerebrally with brain
suspension from mule deer naturally affected with CWD. Between 24 and 27
months postinoculation, 3 animals became recumbent and were euthanized.
Gross necropsies revealed emaciation in 2 animals and a large pulmonary
abscess in the third. Brains were examined for protease-resistant prion
protein (PrP(res)) by immunohistochemistry and Western blotting and for
scrapie-associated fibrils (SAFs) by negative-stain electron microscopy.
Microscopic lesions in the brain were subtle in 2 animals and absent in
the third case. However, all 3 animals were positive for PrP(res) by
immunohistochemistry and Western blot, and SAFs were detected in 2 of
the animals. An uninoculated control animal euthanized during the same
period did not have PrP(res) in its brain. These are preliminary
observations from a currently in-progress experiment. Three years after
the CWD challenge, the 10 remaining inoculated cattle are alive and
apparently healthy. These preliminary findings demonstrate that
diagnostic techniques currently used for bovine spongiform
encephalopathy (BSE) surveillance would also detect CWD in cattle should
it occur naturally.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11243374&dopt=Abstract

Sat, Nov 23, 2002

Scientists unsure if CWD can jump species

By Jessica Bock Wausau Daily Herald jbock@wdhprint.com

snip...

Janice Miller, a veterinarian in charge of the experiment, said she
believes previous research shows it is hard for the disease to be
transmitted naturally from whitetail deer to dairy cattle. "Our study
says nothing of how it could be transmitted in natural surroundings,"
she said.

Miller has been studying the transmission of CWD from mule deer to
cattle since 1997. Since then, chronic wasting disease was transmitted
to four out of 13 cattle injected with brain tissue from naturally
infected mule deer, she said.

In Wyoming, Williams has been studying cattle that were given a
concoction of diseased brain tissue orally, and five years into the
study the animals remain healthy, Miller said. No one knows if chronic
wasting disease could ever spread to another species through natural
surroundings.

"Our experience is that it's pretty hard to predict," Miller said.

http://www.wausaudailyherald.com/wdhlocal/277564794712612.shtml

greetings list,

> Since then, chronic wasting disease was

> transmitted to four out of 13 cattle

is this a typo by the media or has another cow gone down with CWD since
the preliminary findings were found?

TSS

########### http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############


-------- Original Message --------
Subject: Re: CWD TO CATTLE by inoculation (ok,is it three or four OR NOW FIVE???)
Date: Mon, 23 Jun 2003 12:36:59 -0500
From: "Janice M. Miller"
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@uni-karlsruhe.de

######## Bovine Spongiform Encephalopathy #########

I am happy to provide an update on the experimental inoculation of
cattle and sheep with CWD. These are ongoing experiments and updates
are normally provided via presentations at meetings. Dr. Hamir has
prepared a poster of the following information that will be displayed at
4 upcoming meetings this summer and fall.

Experimental Transmission of Chronic Wasting Disease (CWD) to Cattle
and Sheep
Progress report - June 23, 2003

Experimental Transmission to Cattle

Background:
In 1997, 13 calves were inoculated intracerebrally with brain
suspension from mule deer naturally affected with CWD. During the first
3 years, 3 animals were euthanized 23, 24, and 28 months after
inoculation because of weight loss (2) or sudden death (1). Although
microscopic examination of the brains did not show classical lesions of
transmissible spongiform encephalopathy (TSE), a specific TSE marker
protein, PrPres, was detected by immunohistochemistry (IHC) and western
blot. Detailed information on these animals has been published
previously (A Hamir et al., J Vet Diagn Invest 13: 91-96, 2001).

Update:
During the 3rd, 4th and 6th years of observation, 7 additional animals
have been euthanized due to a variety of health concerns (primarily
chronic joint and foot problems). IHC and western blot results indicate
that 2 of these animals, necropsied 59 and 63 months after inoculation,
were positive for PrPres. One animal (# 1746) had not been eating well
for approximately 1 week prior to being found recumbent. At necropsy,
significant gross lesions consisted of an oblique fracture of L1
vertebral arch with extension into the body, and moderate multifocal
hemorrhagic ulceration in the abomasum. Microscopic examination of
brain revealed a few isolated neurons with single or multiple vacuoles,
but neither neuronal degeneration nor gliosis was observed. IHC
revealed the presence of PrPres in sections from several areas of the
brain. The other PrPres positive animal (#1742) was euthanized after
being found in lateral recumbency with a body temperature of 104.6 F.
It had not shown prior clinical signs except for some decreased appetite
for 2 days. Necropsy revealed only moderate hepatitis and a small renal
infarct due to intravascular thrombosis.

Summary of findings on all necropsied animals to date:

Ear tag Date of Survival Disease Clinical
Histo- IHC WB
no. necropsy period course signs
pathology
_____________________________________________________________________
1745 8/18/99 23m 2m +
± + +
1768 9/22/99 24m 3m +
± + +
1744 1/29/00 28m 3d ±
- + +
1749 5/20/01 44m NA -
- - -
1748 6/27/01 45m NA -
- - -
1743 8/21/02 59m NA -
- - -
1741 8/22/02 59m NA -
- - -
1746 8/27/02 59m 7d ±
± + +
1765 11/27/02 62m 1d ±
± - -
1742 12/28/02 63m 2d ±
- + +
NT = not tested; IHC = immunohistochemistry for PrPres; SAF = scrapie
associated fibrils; NA = not applicable; WB = Western blot
(Prionics-Check); + = lesions or antigen present; - = lesions or
antigen absent; ± = signs/lesions equivocal; i/c = intracerebral; m =
months; d = days.

Summary:
After 5.75 years of observation we have 5 CWD transmissions to cattle
from a group of 13 inoculates. These animals, which were necropsied 23,
24, 28, 59, and 63 months after inoculation, did not show the clinical
signs or histopathologic lesions typical of a TSE, but PrPres was
detected in brain samples by both immunohistochemistry and western blot.
Five other animals necropsied during the 4th, 5th and 6th years of
observation have not shown evidence of PrPres and the remaining 3 cattle
are apparently healthy. Note that this study involved direct
intracerebral inoculation of cattle with the CWD agent, which is an
unnatural route of exposure. Likely, it would be more difficult to
infect cattle by the oral route. Cattle have been inoculated orally at
the University of Wyoming with the same inoculum used in this
experiment, and 5.75 years into the study the animals remain healthy
(personal communication, Dr. Beth Williams).

Experimental Transmission of CWD to sheep

Eight Suffolk sheep from the NADC scrapie-free flock were inoculated
intracerebrally with the CWD brain suspension used to inoculate cattle.
PRNP genotyping showed that 4 of the sheep were QQ at codon 171 and the
other four were QR. Two of the QQ sheep were euthanized during the 3rd
year of observation. At necropsy one of these animals had a urethral
obstruction and PrPres was not detected in brain or lymphoid tissues.
The other sheep, necropsied 35 months after inoculation, showed clinical
signs and histopathologic lesions that were indistinguishable from
scrapie. IHC tests showed typical PrPres accumulations in brain,
tonsil, and some lymph nodes. The 2 remaining QQ sheep and all 4 QR
sheep are apparently healthy 47 months after inoculation.

Summary:
After 4 years of observation we have 1 transmission of CWD to a 171 QQ
sheep. This animal, which was necropsied 35 months after inoculation,
showed clinical signs and histopathologic lesions that were
indistinguishable from scrapie. Another QQ sheep that was necropsied
during the 3rd year showed no evidence of prion disease and all
remaining sheep (2 QQ and 4 QR) are apparently healthy.

########### http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############

-------- Original Message --------

Subject: Previous message
Date: Wed, 25 Jun 2003 15:07:52 -0500
From: "Janice M. Miller"
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@uni-karlsruhe.de

######## Bovine Spongiform Encephalopathy #########

I see that my previous message didn't include the questions that
triggered my response. Terry had asked what I thought we could conclude
from the experiment in which we had 1 CWD transmission to a sheep. His
other question was about the Vermont sheep flock that was depopulated a
couple of years ago because of some evidence for an unknown TSE in some
animals.

########### http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html ############




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