Agreement Reached with Owner to De-Populate CWD Deer at Davis County Hunting Preserve Iowa
Agreement Reached with Owner to De-Populate Deer at Davis County Hunting
Preserve
Posted: 09/10/2012
DES MOINES – An agreement has been reached with the owner of a hunting
preserve in Davis County to depopulate the facility of all deer and elk within
the next several months following Iowa’s first positive detection of chronic
wasting disease (CWD) there.
The agreement, signed Friday by Iowa Department of Natural Resources
Director Chuck Gipp and the owners of Pine Ridge Hunting Lodge in Davis County,
contains a number of provisions to help contain the potential spreading of CWD
from the facility.
“We are very pleased with agreement and we want to commend the owners for
working with us in taking this important step needed to help contain the
spreading of CWD,” said Gipp.
Under terms of the agreement to depopulate the facility, Pine Ridge Hunting
Lodge will be able to conduct hunts previously scheduled between Sept. 8 and
Dec. 25. However, only antlers attached to a clean skull plate and the animal’s
cape will be allowed to leave the facility and only after samples for CWD and
DNA have been collected. Pine Ridge is required to provide 12-hour notice to the
DNR once any animal has been harvested so that tissue samples can be
collected.
Other key components of the agreement include:
A refrigerated truck will be provided by Pine Ridge to store carcasses of
deer until sample results for CWD have been confirmed. Pine Ridge will pay for
all CWD testing and disposal of animals taken during the planned hunts at its
facility. A 3-D electric fence shall be installed jointly by Pine Ridge and the
DNR on the inside of the existing perimeter boundary fence of the facility with
the cost of the electric fence being split evenly. The agreement also provides
for repair of any fencing should the need arise. A future operational plan for
Pine Ridge will be developed in conjunction with the DNR after depopulation is
complete.
After the first positive sample of the deer in Davis County was confirmed
in July, both DNR and the Iowa Department of Agriculture and Land Stewardship
(IDALS) have been working to trace back deer that have moved to and from the
Cerro Gordo County facility. From this effort, five deer at a breeding facility
in Pottawattamie County have been identified as having tested positive for CWD
placing that operation under quarantine.
In addition, 14 deer from the breeding facility in Cerro Gordo County have
been sampled for CWD with one yielding a positive result for CWD. The Cerro
Gordo facility is also currently under quarantine meaning live animals are not
allowed to come or go from the operation.
The DNR has regulatory authority on hunting preserves while IDALS regulates
captive breeding herds.
The 330-acre Davis County facility is currently surrounded by an eight-foot
high fence and routine inspections are being conducted by the DNR to ensure the
integrity of the fencing system so that no deer are coming or going from the
area.
The DNR will increase testing of wild deer in the area by working with
hunters and landowners to collect samples from hunter harvested deer beginning
this fall.
There is no evidence that CWD can spread to humans, pets or domestic
livestock such as pork, beef, dairy, poultry, sheep or goats.
Iowa has tested 42,557 wild deer and over 4,000 captive deer and elk as
part of the surveillance program since 2002 when CWD was found in Wisconsin.
CWD is a neurological disease that only affects deer, elk and moose. It is
caused by an abnormal protein, called a prion, which affects the brains of
infected animals, causing them to lose weight, display abnormal behavior and
lose bodily functions. Signs include excessive salivation, thirst and urination,
loss of appetite, progressive weight loss, listlessness and drooping ears and
head.
CWD can be transferred from animal to animal through contact with bodily
excretions and the prions can also attach to soil and spread the disease among
deer. Chronic wasting disease was first identified in captive mule deer at a
research facility in Colorado in 1967. Prior to the positive detection in Iowa,
CWD had been detected in every bordering state.
> There is no evidence that CWD can spread to humans, pets or domestic
livestock such as pork, beef, dairy, poultry, sheep or goats.
that’s simply not true. please see ;
UPDATED CORRESPONDENCE FROM AUTHORS OF THIS STUDY I.E. COLBY, PRUSINER ET
AL, ABOUT MY CONCERNS OF THE DISCREPANCY BETWEEN THEIR FIGURES AND MY FIGURES OF
THE STUDIES ON CWD TRANSMISSION TO CATTLE ;
CWD to cattle figures CORRECTION
Greetings,
I believe the statement and quote below is incorrect ;
"CWD has been transmitted to cattle after intracerebral inoculation,
although the infection rate was low (4 of 13 animals [Hamir et al. 2001]). This
finding raised concerns that CWD prions might be transmitted to cattle grazing
in contaminated pastures."
Please see ;
Within 26 months post inoculation, 12 inoculated animals had lost weight,
revealed abnormal clinical signs, and were euthanatized. Laboratory tests
revealed the presence of a unique pattern of the disease agent in tissues of
these animals. These findings demonstrate that when CWD is directly inoculated
into the brain of cattle, 86% of inoculated cattle develop clinical signs of the
disease.
" although the infection rate was low (4 of 13 animals [Hamir et al.
2001]). "
shouldn't this be corrected, 86% is NOT a low rate. ...
kindest regards,
Terry S. Singeltary Sr. P.O. Box 42 Bacliff, Texas USA 77518
Thank you!
Thanks so much for your updates/comments. We intend to publish as rapidly
as possible all updates/comments that contribute substantially to the topic
under discussion.
re-Prions David W. Colby1,* and Stanley B. Prusiner1,2 + Author
Affiliations
1Institute for Neurodegenerative Diseases, University of California, San
Francisco, San Francisco, California 94143 2Department of Neurology, University
of California, San Francisco, San Francisco, California 94143 Correspondence:
stanley@ind.ucsf.edu
Mule deer, white-tailed deer, and elk have been reported to develop CWD. As
the only prion disease identified in free-ranging animals, CWD appears to be far
more communicable than other forms of prion disease. CWD was first described in
1967 and was reported to be a spongiform encephalopathy in 1978 on the basis of
histopathology of the brain. Originally detected in the American West, CWD has
spread across much of North America and has been reported also in South Korea.
In captive populations, up to 90% of mule deer have been reported to be positive
for prions (Williams and Young 1980). The incidence of CWD in cervids living in
the wild has been estimated to be as high as 15% (Miller et al. 2000). The
development of transgenic (Tg) mice expressing cervid PrP, and thus susceptible
to CWD, has enhanced detection of CWD and the estimation of prion titers
(Browning et al. 2004; Tamgüney et al. 2006). Shedding of prions in the feces,
even in presymptomatic deer, has been identified as a likely source of infection
for these grazing animals (Williams and Miller 2002; Tamgüney et al. 2009b). CWD
has been transmitted to cattle after intracerebral inoculation, although the
infection rate was low (4 of 13 animals [Hamir et al. 2001]). This finding
raised concerns that CWD prions might be transmitted to cattle grazing in
contaminated pastures.
snip...
----- Original Message -----
From: David Colby To: flounder9@verizon.net
Cc: stanley@XXXXXXXX
Sent: Tuesday, March 01, 2011 8:25 AM
Subject: Re: FW: re-Prions David W. Colby1,* and Stanley B. Prusiner1,2 +
Author Affiliations
Dear Terry Singeltary,
Thank you for your correspondence regarding the review article Stanley
Prusiner and I recently wrote for Cold Spring Harbor Perspectives. Dr. Prusiner
asked that I reply to your message due to his busy schedule. We agree that the
transmission of CWD prions to beef livestock would be a troubling development
and assessing that risk is important. In our article, we cite a peer-reviewed
publication reporting confirmed cases of laboratory transmission based on
stringent criteria. The less stringent criteria for transmission described in
the abstract you refer to lead to the discrepancy between your numbers and ours
and thus the interpretation of the transmission rate. We stand by our assessment
of the literature--namely that the transmission rate of CWD to bovines appears
relatively low, but we recognize that even a low transmission rate could have
important implications for public health and we thank you for bringing attention
to this matter. Warm Regards, David Colby -- David Colby, PhDAssistant Professor
Department of Chemical Engineering University of Delaware
===========END...TSS==============
SNIP...SEE FULL TEXT ;
UPDATED DATA ON 2ND CWD STRAIN Wednesday, September 08, 2010 CWD PRION
CONGRESS SEPTEMBER 8-11 2010
Sunday, August 19, 2012
Susceptibility of cattle to the agent of chronic wasting disease from elk
after intracranial inoculation 2012
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF
TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES Location: Virus and Prion Research
Unit
PO-081: Chronic wasting disease in the cat— Similarities to feline
spongiform encephalopathy (FSE)
PO-081: Chronic wasting disease in the cat— Similarities to feline
spongiform encephalopathy (FSE)
Thursday, May 31, 2012
CHRONIC WASTING DISEASE CWD PRION2012 Aerosol, Inhalation transmission,
Scrapie, cats, species barrier, burial, and more
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed
deer
Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture;
Agricultural Research Service, National Animal Disease Center; Ames, IA USA
Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture;
Agricultural Research Service, National Animal Disease Center; Ames, IA USA
Interspecies transmission studies afford the opportunity to better
understand the potential host range and origins of prion diseases. The purpose
of these experiments was to determine susceptibility of white-tailed deer (WTD)
to scrapie and to compare the resultant clinical signs, lesions, and molecular
profiles of PrPSc to those of chronic wasting disease (CWD). We inoculated WTD
intracranially (IC; n = 5) and by a natural route of exposure (concurrent oral
and intranasal (IN); n = 5) with a US scrapie isolate.
All deer were inoculated with a 10% (wt/vol) brain homogenate from sheep
with scrapie (1ml IC, 1 ml IN, 30 ml oral). All deer inoculated by the
intracranial route had evidence of PrPSc accumulation. PrPSc was detected in
lymphoid tissues as early as 7 months-post-inoculation (PI) and a single deer
that was necropsied at 15.6 months had widespread distribution of PrPSc
highlighting that PrPSc is widely distributed in the CNS and lymphoid tissues
prior to the onset of clinical signs. IC inoculated deer necropsied after 20
months PI (3/5) had clinical signs, spongiform encephalopathy, and widespread
distribution of PrPSc in neural and lymphoid tissues.
The results of this study suggest that there are many similarities in the
manifestation of CWD and scrapie in WTD after IC inoculation including early and
widespread presence of PrPSc in lymphoid tissues, clinical signs of depression
and weight loss progressing to wasting, and an incubation time of 21-23 months.
Moreover, western blots (WB) done on brain material from the obex region have a
molecular profile similar to CWD and distinct from tissues of the cerebrum or
the scrapie inoculum. However, results of microscopic and IHC examination
indicate that there are differences between the lesions expected in CWD and
those that occur in deer with scrapie: amyloid plaques were not noted in any
sections of brain examined from these deer and the pattern of immunoreactivity
by IHC was diffuse rather than plaque-like.
After a natural route of exposure, 100% of WTD were susceptible to scrapie.
Deer developed clinical signs of wasting and mental depression and were
necropsied from 28 to 33 months PI. Tissues from these deer were positive for
PrPSc by IHC and WB. Similar to IC inoculated deer, samples from these deer
exhibited two different molecular profiles: samples from obex resembled CWD
whereas those from cerebrum were similar to the original scrapie inoculum. On
further examination by WB using a panel of antibodies, the tissues from deer
with scrapie exhibit properties differing from tissues either from sheep with
scrapie or WTD with CWD. Samples from WTD with CWD or sheep with scrapie are
strongly immunoreactive when probed with mAb P4, however, samples from WTD with
scrapie are only weakly immunoreactive. In contrast, when probed with mAb’s 6H4
or SAF 84, samples from sheep with scrapie and WTD with CWD are weakly
immunoreactive and samples from WTD with scrapie are strongly positive.
This work demonstrates that WTD are highly susceptible to sheep scrapie,
but on first passage, scrapie in WTD is differentiable from CWD.
PO-039: A comparison of scrapie and chronic wasting disease in white-tailed
deer
Justin Greenlee, Jodi Smith, Eric Nicholson US Dept. Agriculture;
Agricultural Research Service, National Animal Disease Center; Ames, IA USA
White-tailed deer are susceptible to the agent of sheep scrapie by
intracerebral inoculation
snip...
It is unlikely that CWD will be eradicated from free-ranging cervids, and
the disease is likely to continue to spread geographically [10]. However, the
potential that white-tailed deer may be susceptible to sheep scrapie by a
natural route presents an additional confounding factor to halting the spread of
CWD. This leads to the additional speculations that
1) infected deer could serve as a reservoir to infect sheep with scrapie
offering challenges to scrapie eradication efforts and
2) CWD spread need not remain geographically confined to current endemic
areas, but could occur anywhere that sheep with scrapie and susceptible cervids
cohabitate.
This work demonstrates for the first time that white-tailed deer are
susceptible to sheep scrapie by intracerebral inoculation with a high attack
rate and that the disease that results has similarities to CWD. These
experiments will be repeated with a more natural route of inoculation to
determine the likelihood of the potential transmission of sheep scrapie to
white-tailed deer. If scrapie were to occur in white-tailed deer, results of
this study indicate that it would be detected as a TSE, but may be difficult to
differentiate from CWD without in-depth biochemical analysis.
White-tailed Deer are Susceptible to Scrapie by Natural Route of Infection
Jodi D. Smith, Justin J. Greenlee, and Robert A. Kunkle; Virus and Prion
Research Unit, National Animal Disease Center, USDA-ARS
Interspecies transmission studies afford the opportunity to better
understand the potential host range and origins of prion diseases. Previous
experiments demonstrated that white-tailed deer are susceptible to sheep-derived
scrapie by intracranial inoculation. The purpose of this study was to determine
susceptibility of white-tailed deer to scrapie after a natural route of
exposure. Deer (n=5) were inoculated by concurrent oral (30 ml) and intranasal
(1 ml) instillation of a 10% (wt/vol) brain homogenate derived from a sheep
clinically affected with scrapie. Non-inoculated deer were maintained as
negative controls. All deer were observed daily for clinical signs. Deer were
euthanized and necropsied when neurologic disease was evident, and tissues were
examined for abnormal prion protein (PrPSc) by immunohistochemistry (IHC) and
western blot (WB). One animal was euthanized 15 months post-inoculation (MPI)
due to an injury. At that time, examination of obex and lymphoid tissues by IHC
was positive, but WB of obex and colliculus were negative. Remaining deer
developed clinical signs of wasting and mental depression and were necropsied
from 28 to 33 MPI. Tissues from these deer were positive for scrapie by IHC and
WB. Tissues with PrPSc immunoreactivity included brain, tonsil, retropharyngeal
and mesenteric lymph nodes, hemal node, Peyer’s patches, and spleen. This work
demonstrates for the first time that white-tailed deer are susceptible to sheep
scrapie by potential natural routes of inoculation. In-depth analysis of tissues
will be done to determine similarities between scrapie in deer after
intracranial and oral/intranasal inoculation and chronic wasting disease
resulting from similar routes of inoculation.
see full text ;
*** Spraker suggested an interesting explanation for the occurrence of CWD.
The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr.
Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at
this site. When deer were introduced to the pens they occupied ground that had
previously been occupied by sheep.
(PLEASE NOTE SOME OF THESE OLD UK GOVERNMENT FILE URLS ARE SLOW TO OPEN,
AND SOMETIMES YOU MAY HAVE TO CLICK ON MULTIPLE TIMES, PLEASE BE PATIENT, ANY
PROBLEMS PLEASE WRITE ME PRIVATELY, AND I WILL TRY AND FIX OR SEND YOU OLD PDF
FILE...TSS)
Wednesday, February 16, 2011
IN CONFIDENCE
SCRAPIE TRANSMISSION TO CHIMPANZEES
IN CONFIDENCE
Chronic Wasting Disease Susceptibility of Four North American Rodents
Chad J. Johnson1*, Jay R. Schneider2, Christopher J. Johnson2, Natalie A.
Mickelsen2, Julia A. Langenberg3, Philip N. Bochsler4, Delwyn P. Keane4, Daniel
J. Barr4, and Dennis M. Heisey2 1University of Wisconsin School of Veterinary
Medicine, Department of Comparative Biosciences, 1656 Linden Drive, Madison WI
53706, USA 2US Geological Survey, National Wildlife Health Center, 6006
Schroeder Road, Madison WI 53711, USA 3Wisconsin Department of Natural
Resources, 101 South Webster Street, Madison WI 53703, USA 4Wisconsin Veterinary
Diagnostic Lab, 445 Easterday Lane, Madison WI 53706, USA *Corresponding author
email: cjohnson@svm.vetmed.wisc.edu
We intracerebrally challenged four species of native North American rodents
that inhabit locations undergoing cervid chronic wasting disease (CWD)
epidemics. The species were: deer mice (Peromyscus maniculatus), white-footed
mice (P. leucopus), meadow voles (Microtus pennsylvanicus), and red-backed voles
(Myodes gapperi). The inocula were prepared from the brains of hunter-harvested
white-tailed deer from Wisconsin that tested positive for CWD. Meadow voles
proved to be most susceptible, with a median incubation period of 272 days.
Immunoblotting and immunohistochemistry confirmed the presence of PrPd in the
brains of all challenged meadow voles. Subsequent passages in meadow voles lead
to a significant reduction in incubation period. The disease progression in
red-backed voles, which are very closely related to the European bank vole (M.
glareolus) which have been demonstrated to be sensitive to a number of TSEs, was
slower than in meadow voles with a median incubation period of 351 days. We
sequenced the meadow vole and red-backed vole Prnp genes and found three amino
acid (AA) differences outside of the signal and GPI anchor sequences. Of these
differences (T56-, G90S, S170N; read-backed vole:meadow vole), S170N is
particularly intriguing due its postulated involvement in "rigid loop" structure
and CWD susceptibility. Deer mice did not exhibit disease signs until nearly 1.5
years post-inoculation, but appear to be exhibiting a high degree of disease
penetrance. White-footed mice have an even longer incubation period but are also
showing high penetrance. Second passage experiments show significant shortening
of incubation periods. Meadow voles in particular appear to be interesting lab
models for CWD. These rodents scavenge carrion, and are an important food source
for many predator species. Furthermore, these rodents enter human and domestic
livestock food chains by accidental inclusion in grain and forage. Further
investigation of these species as potential hosts, bridge species, and
reservoirs of CWD is required.
please see ;
Volume 18, Number 3—March 2012
Samuel E. Saunders1, Shannon L. Bartelt-Hunt, and Jason C. Bartz
Author affiliations: University of Nebraska-Lincoln, Omaha, Nebraska, USA
(S.E. Saunders, S.L. Bartelt-Hunt); Creighton University, Omaha (J.C. Bartz)
Synopsis
Occurrence, Transmission, and Zoonotic Potential of Chronic Wasting Disease
snip...
Most epidemiologic studies and experimental work have suggested that the
potential for CWD transmission to humans is low, and such transmission has not
been documented through ongoing surveillance (2,3). In vitro prion replication
assays report a relatively low efficiency of CWD PrPSc-directed conversion of
human PrPc to PrPSc (30), and transgenic mice overexpressing human PrPc are
resistant to CWD infection (31); these findings indicate low zoonotic potential.
However, squirrel monkeys are susceptible to CWD by intracerebral and oral
inoculation (32). Cynomolgus macaques, which are evolutionarily closer to humans
than squirrel monkeys, are resistant to CWD infection (32). Regardless, the
finding that a primate is orally susceptible to CWD is of concern...
snip...
Reasons for Caution There are several reasons for caution with respect to
zoonotic and interspecies CWD transmission. First, there is strong evidence that
distinct CWD strains exist (36). Prion strains are distinguished by varied
incubation periods, clinical symptoms, PrPSc conformations, and CNS PrPSc
depositions (3,32). Strains have been identified in other natural prion
diseases, including scrapie, BSE, and CJD (3). Intraspecies and interspecies
transmission of prions from CWD-positive deer and elk isolates resulted in
identification of >2 strains of CWD in rodent models (36), indicating that
CWD strains likely exist in cervids. However, nothing is currently known about
natural distribution and prevalence of CWD strains. Currently, host range and
pathogenicity vary with prion strain (28,37). Therefore, zoonotic potential of
CWD may also vary with CWD strain. In addition, diversity in host (cervid) and
target (e.g., human) genotypes further complicates definitive findings of
zoonotic and interspecies transmission potentials of CWD.
Intraspecies and interspecies passage of the CWD agent may also increase
the risk for zoonotic CWD transmission. The CWD prion agent is undergoing serial
passage naturally as the disease continues to emerge. In vitro and in vivo
intraspecies transmission of the CWD agent yields PrPSc with an increased
capacity to convert human PrPc to PrPSc (30). Interspecies prion transmission
can alter CWD host range (38) and yield multiple novel prion strains (3,28). The
potential for interspecies CWD transmission (by cohabitating mammals) will only
increase as the disease spreads and CWD prions continue to be shed into the
environment. This environmental passage itself may alter CWD prions or exert
selective pressures on CWD strain mixtures by interactions with soil, which are
known to vary with prion strain (25), or exposure to environmental or gut
degradation.
Given that prion disease in humans can be difficult to diagnose and the
asymptomatic incubation period can last decades, continued research,
epidemiologic surveillance, and caution in handling risky material remain
prudent as CWD continues to spread and the opportunity for interspecies
transmission increases. Otherwise, similar to what occurred in the United
Kingdom after detection of variant CJD and its subsequent link to BSE, years of
prevention could be lost if zoonotic transmission of CWD is subsequently
identified,...
snip...
Sunday, January 22, 2012
Chronic Wasting Disease CWD cervids interspecies transmission
Saturday, September 01, 2012
Resistance of Soil-Bound Prions to Rumen Digestion
Friday, July 20, 2012
CWD found for first time in Iowa at hunting preserve
Wednesday, September 05, 2012
Additional Facility in Pottawatamie County Iowa Under Quarantine for CWD
after 5 deer test positive
meanwhile, Texas is still floundering after two recent CWD confirmations,
and a decade of CWD waltzing across it’s borders. what’s another decade, right
$$$
Friday, September 07, 2012
Texas Wildlife Officials Considering New Deer Movement Rules in Response to
CWD
TSS
posted by Terry S. Singeltary Sr. at
10:20 AM
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