Missouri Final action on Orders of Rule making Breeders and Big Game
Hunting Preserves
RECOMMENDATION FOR:
Final action on Orders of Rule making, which are attached for Commission
consideration. All changes will be effective as soon as possible after
publication in the Missouri Register. ACTION ITEMS:
3 CSR 10-4:1 10 General Prohibition; Applications.
• Provides for clarification of the rule with respect to wildlife raised or
held in captivity.
3 CSR 10-9.220 Wildlife Confinement Standards.
• Changes term "wild animals" to "wildlife."
• Enhanced fence standards for all new facilities:
o Single 8' fence.
o Additional requirements related to materials· and spacing of
fences.
o Existing facilities -will have 24 months from the effective date of the
rule to meet enhanced fencing standards.
• Class I and Class II Wildlife Breeder Permits are also used by auction
houses and other businesses that serve as "brokers" for cervids that are bought
and sold. Many animals may move through facilities owned by these businesses and
may be held in confined areas that have recently held animals from herds of
variable disease status. Existing Wildlife Breeder Permit regulations· were not
designed to address such operations and may not adequately describe the
conditions under which these businesses should be operated. Removed exemption
for temporary exhibits and auction sites.
• Deer must be inside of an approved ·facility which meets the standards
shown earlier unless they are on a truck between facilities and the driver. has
a valid/completed CVI or Breeder Movement Certificate.
• Use of the term "cervid" only occurs in section (3) as this will dictate
confinement for Breeders and Big Game Hunting Preserves. The remaining changes
are specific to "white-tailed deer or mule deer".
3 CSR 10-9.353 Privileges of Class I and Class II Wildlife Breeders.
• New applicants for a Class I Wildlife Breeders Permit to hold
white-tailed deer or mule deer must take an exam.
o Class II Wildlife Breeders are already required to pass an exam.
• Ban importation of live white-tailed deer, mule deer or their
hybrids.
o A similar ban on importation of skunks, foxes, racoons, and coyotes due
to disease concerns has been in place for years.
• Requires an onsite inspection prior to and after construction of a new
facility as part of the application process.
• Removes the exemption that allowed non-residents to ship, transport,
hold, and consign deer without a premit.
o Non-residents may do business in Missouri under the following
circumstances:
§ If they have a Missouri Wildlife Breeder or Licensed Hunting Preserve
Permit. In order to have this permit, they must have a permitted facility in
Missouri.
§ If they purchase a deer from a Missouri permit holder, have the
appropriate permit from their home state, and a completed Certificate of
Veterinarian Inspection (CVI) from Missouri they may transport the animal(s) out
of the state, but they cannot "hold" them in Missouri without a Missouri
permit.
§ If they purchase an animal from a facility permitted by the Department,
they can have that animal shipped to them if the shipper has the completed
CVI.
• Shipping between permitted facilities may occur if the shipper has in
their possession a completed Breeder Movement Certificate
• Removes the exemption that allowed wildlife breeders to exhibit
white-tailed deer or mule deer in locations other than the one listed on the
permit. This change removes the exemption for holding deer in temporary
facilities for display. Deer must be inside an approved facility which meets the
standards shown earlier unless they are on a truck between facilities and the
driver has a valid/completed CVI or Breeder Movement Certificate.
• Requires CWD samples, to be collected by a veterinarian, for all
mortalities of whitetailed deer, mule deer, or their hybrids 6 months old or
older.
o The Department reserves the right to require more disease sampling during
mortality/morbidity events.
o Under certain conditions, the director may exempt a permit holder from
this rule due to a mass casualty/mortality event.
§ The exemption must orginate from an accredited veterinarian and be
reported to a conservation agent, Protection regional supervisor, or the state
wildlife veterinarian of the Department.
§ The permit holder must allow the Department access to collect disease
samples from all known cervid mortalities, pertaining to, and in the event of a
mass casualty/mortality event.
• Class I and Class II wildlife breeders that hold white-tailed deer, mule
deer, or their hybrids must be enrolled in a USDA-approved CWD-herd certifcation
program.
• Confirmed positive test results must be reported to the conservation
agent and state wildlife veterinarian.
• Requires compliance with a Department-approved disease response plan if
CWD is discovered.
• Requires documentation and records for movement of white-tailed deer or
mule deer. o Requires documents be kept for 5 years.
o Source herds must be in a USDA-approved CWD-herd certification program.
• No permits will be issued for a period of five years for a new facility
within 25 miles of where a CWD-postive has been confirmed.
3 CSR 10-9.359 Class I and Class II Wildlife Breeder: Records
Required.
• Requires annual herd inventory, presence of a veterinarian during the
annual inventory, signature of veterinarian on herd records, individual animal
identification, and individual animal documentation, including CWD testing
results.
o Specifies 5 years as the minimum period of time that records must be
kept.
3 CSR 10-9.560 Licensed Hunting Preserve Permit
• This amendment disallows propagating, holding in captivity, and hunting
hogs within a big game hunting preserve unless already approved by a specific
date.
3 CSR 10-9.565 Licensed Hunting Preserve: Privileges.
• Changes fencing “height” to “requirements” as specified in 3 CSR
10-9.220.
• Requires CWD sampling, collected by a veterinarian, for all cervid
mortalities that are 6- months old or older.
o The Department reserves the right to require more disease sampling during
mortality/morbidity events.
o Under certain conditions, the director may exempt a permit holder from
this rule in the event of a mass casualty/mortality event.
§ The exemption must orginate from an accredited veterinarian and be
reported to a conservation agent, Protection regional supervisor, or the state
wildlife veterinarian of the Department.
§ The permit holder must allow the Department access to collect disease
samples from all known cervid mortalities, pertaining to, and in the event of a
mass casualty/mortality event.
• Confirmed positive disease results must be reported to the conservation
agent and state wildlife veterinarian.
• Requires compliance with a Department-approved disease response plan if
CWD is discovered.
• Requires documentation and records for movement of cervids.
o Require documents be kept for 5 years.
o Source herds must participate in a USDA-approved CWD-herd certification
program.
• No new permits will be issued for a period of five years for facilities
within 25 miles of where a CWD postive has been confirmed.
• Bans holding imported live cervids in a big game hunting preserve.
• Use of the term “cervid” as all deer are considered game within a big
game hunting preserve. Used in reference to specific fencing standards and CWD
testing.
3 CSR 10-9.566 Licensed Hunting Preserve: Records Required.
• Requires a system of inventory for acquired ungulates that includes
individual animal identification and documentation and CWD test results.
o Specifies 5 years as the minimum period of time that records must be
kept.
o If privileges of a wildlife breeder are exercised, records must follow
breeder requirements.
ORDER OF RULEMAKING
By the authority vested in the Conservation Commission under sections 40
and 45 of Art. IV, Mo. Const., the commission amends a rule as follows:
3 CSR 10-4.110 General Prohibition; Applications is amended.
A notice of proposed rulemaking containing the text of the proposed
amendment was published in the Missouri Register on July 15, 2014 (39 MoReg
1200-1201). No changes have been made in the text of the proposed amendment, so
it is not reprinted here. This proposed amendment becomes effective thirty (30)
days after publication in the Code of State Regulations.
SUMMARY OF COMMENTS: While there were no comments directly relating to this
amendment, the commission received three hundred six (306) comments from
individuals who indicated that captive white-tailed deer, mule deer, and their
hybrids should not be considered “livestock”. Forty-eight (48) comments were
received from individuals that believe any privately-owned captive white-tailed
deer, mule deer, or their hybrids held behind high fences should be considered
“livestock”, not wildlife.
In addition, one thousand nine hundred and eighty-three (1,983) comments
were received from individuals who expressed general support for stricter
regulation of the captive cervid industry and one hundred fifty-four (154)
comments were submitted by individuals who voiced general opposition to all
proposed changes.
RESPONSE: In response to the comments that captive deer should be
considered livestock, not wildlife, captive deer have been considered wildlife
and regulated by the Conservation Commission since the Commission was created in
1937. White-tailed deer and mule deer are wild by nature, regardless of whether
they have been raised in captivity. This is true for other wildlife held in
captivity such as bears, mountain lions, timber rattlesnakes and raccoons. The
proposed amendment simply codifies the Commission’s authority over captive
wildlife that has been in place for over seventy five (75) years.
In response statements regarding the economic contribution of the captive
cervid industry, the department recognizes the economic contribution of the
captive cervid industry and this regulation will not adversely impact that
contribution. Furthermore, twelve thousand (12,000) Missouri jobs and hundreds
of businesses and communities depend on the approximately $1 billion boost in
economic activity related to deer hunting and watching that is supported by five
hundred twenty thousand (520,000) deer hunters, millions of wildlife watchers,
and thousands of landowners.
In response to the seriousness of the threat posed to Missouri’s captive
and free-ranging deer population by chronic wasting disease (CWD), CWD is
transmitted by prions, which are abnormal proteins that attack the nervous
system, and is always fatal to the infected animal. There is currently no
approved live test for CWD, with the only approved test being performed
post-mortem. CWD is spread both directly from deer to deer and indirectly to
deer from infected soil and other surfaces. The CWD prions accumulate in the
brain, spinal cord, eyes, spleen and lymph nodes of infected animals. Once well
established in an area, CWD is impossible to eradicate. States with CWD must
focus on limiting the spread of the disease and preventing its introduction to
new areas. CWD could substantially reduce infected cervid populations by
lowering adult survival rates and destabilizing long-term population dynamics.
An example of active management limiting CWD is shown in Illinois where it has
been kept at a low prevalence rate (annual prevalence rate of 0.94 ± 0.23%;
Manjerovic, M.B., M. L. Green, N. Mateus-Pinilla, and J. Novakofski. 2014. The
importance of localized culling in stabilizing chronic wasting disease
prevalence in white-tailed deer populations. Preventive Veterinary Medicine
113(2014):139-145.).
No changes to the rule have been made as a result of these comments.
Title 3—DEPARTMENT OF CONSERVATION
Division 10—Conservation Commission
Chapter 9—Wildlife Code: Confined Wildlife: Privileges, Permits,
Standards
ORDER OF RULEMAKING
By the authority vested in the Conservation Commission under sections 40
and 45 of Art. IV, Mo. Const., the commission amends a rule as follows:
3 CSR 10-9.220 Wildlife Confinement Standards is amended.
A notice of proposed rulemaking containing the text of the proposed
amendment was published in the Missouri Register on July 15, 2014 (39 MoReg
1201-1208). Those sections with changes are reprinted here. This proposed
amendment becomes effective thirty (30) days after publication in the Code of
State Regulations.
SUMMARY OF COMMENTS: The commission received eleven thousand three hundred
twenty-eight (11,328) comments in support of improved fencing standards, several
of whom encouraged the commission to implement more stringent fencing
requirements. The commission received one thousand two hundred fifty (1,250)
comments in opposition to the proposed changes. Those individuals who expressed
opposition to proposed changes believe that captive cervid owners will erect
fences capable of holding the animals in order to protect their investment and
cited concerns regarding overregulation, diminished rights of private property
owners, the onerous cost of complying with the new rules, and the need to
promote and protect small business interests and alternative agriculture. Others
questioned the science used to formulate the proposed regulation changes, the
seriousness of the threat posed to Missouri’s captive and free-ranging deer
population by chronic wasting disease (CWD), and don’t feel additional
regulations are warranted. Still others voiced opposition to the proposed
amendments due to their personal belief that wildlife should not be held behind
fences. The Conservation Commission invited the public to specifically comment
on whether the proposed fencing standards contained in 3 CSR 10-9.220(3) should
be applied to all existing permittees, and if so, what timeframe, if any, should
be allowed for permittees to bring their facility into compliance with the
proposed fencing standards. Of the sixty-three (63) individuals commenting, two
(2) voiced support for “grandfathering” existing facilities while sixty-one (61)
requested that all existing captive cervid facilities be required to comply with
the new regulations. None of those voicing opposition offered a specific
timeframe for enforcement of new regulations for existing facilities.
The commission received three hundred six (306) comments from individuals
who indicated that captive white-tailed deer, mule deer, and their hybrids
should not be considered “livestock” and many voiced opposition to legislation
that would transfer regulatory authority for these animals to the Missouri
Department of Agriculture. Forty-eight (48) comments were received from
individuals that believe any privately-owned captive white-tailed deer, mule
deer, or their hybrids held behind high fences should be considered “livestock”.
Those voicing opposition to the changes noted that the captive cervid industry
is an important contributor to Missouri’s economy and questioned the seriousness
of the threat posed to Missouri’s captive and free-ranging deer population by
CWD.
The commission received no comments regarding the proposal to change
references to “wildlife animals” to “wildlife”, disallow the confinement of
white-tailed deer, mule deer, and their hybrids in mobile exhibits and auction
facilities. However, the department received one thousand nine hundred and
eighty-three (1,983) comments from individuals who expressed general support for
stricter regulation of the captive cervid industry, one hundred fifty-four (154)
comments from individuals who voice general opposition to all proposed changes,
and fifty-nine (59) comments calling for a moratorium on new facilities in
Missouri.
RESPONSE AND EXPLANATION OF CHANGES: In response to comments on concerns of
overregulation, the Conservation Commission goes to great lengths to evaluate
the importance and need for any regulation. Informing and/or educating the
public are always considered first before any regulation is thoroughly vetted in
the Department of Conservation. At times, however, the Department of
Conservation must propose regulations to manage and/or protect the forest, fish,
and wildlife of Missouri. Per its authority granted by the people and the
constitution of Missouri, the Conservation Commission follows a regulatory
process that evaluates the science, internal input, and public input along with
determining if there is absolutely any other option, such as public education,
that can be taken rather than regulation. In response statements regarding the
economic contribution of the captive cervid industry, the department recognizes
the economic contribution of the captive cervid industry and this regulation
will not adversely impact that contribution. Furthermore, 12,000 Missouri jobs
and hundreds of businesses and communities depend on the approximately $1
billion boost in economic activity related to deer hunting and watching that is
supported by 520,000 deer hunters, millions of wildlife watchers, and thousands
of landowners.
In response to comments on the science used to formulate this rule and the
seriousness of the threat posed to Missouri’s captive and free-ranging deer
population by chronic wasting disease (CWD), CWD is transmitted by prions, which
are abnormal proteins that attack the nervous system, and is always fatal to the
infected animal. There is currently no approved live test for CWD, with the only
approved test performed post-mortem. CWD is spread both directly from deer to
deer and indirectly to deer from infected soil and other surfaces. The CWD
prions accumulate in the brain, spinal cord, eyes, spleen and lymph nodes of
infected animals. Once well established in an area, CWD is impossible to
eradicate. States with CWD must focus on limiting the spread of the disease and
preventing its introduction to new areas. CWD could substantially reduce
infected cervid populations by lowering adult survival rates and destabilizing
long-term population dynamics. An example of active management limiting CWD is
shown in Illinois where it has been kept at a low prevalence rate (annual
prevalence rate of 0.94 ± 0.23%; Manjerovic, M.B., M. L. Green, N.
Mateus-Pinilla, and J. Novakofski. 2014. The importance of localized culling in
stabilizing chronic wasting disease prevalence in white-tailed deer populations.
Preventive Veterinary Medicine 113(2014):139-145.).
In response to comments on diminished rights of private property owners,
the department disagrees that the proposed regulation diminishes the rights of
property owners. Property owners will continue to be able to use their property
for breeding and/or hunting captive wildlife. The proposed regulations are
intended to reduce the risk of disease transmission between captive cervids and
free-ranging deer via movement into and out of captive facilities.
***Current requirements in the Wildlife Code have not been sufficient to
prevent the over 150 reported escapes that have occurred over the last three
years.
Conservation Action October 2014
The Conservation Commission met Oct. 16 and 17 at Conservation Department
Headquarters in Jefferson City.
Commissioners present were: •James T. Blair, IV, Chairman •David W. Murphy,
Vice Chairman •Marilynn J. Bradford, Secretary •Don C. Bedell, Member
REGULATIONS
The Commission approved final recommendations for changes to the Wildlife
Code pertaining to captive cervid facilities.
From: Terry S. Singeltary Sr. Sent: Sunday, October 12, 2014 2:15 PM To:
Terry S. Singeltary Sr. Subject: CWD TSE PRION, TISSUE, BODY FLUIDS, AND
ENVIRONMENTAL CONTAMINATION
Quantitative Assessment of Prion Infectivity in Tissues and Body Fluids by
RT-QuIC
Davin M. Henderson1, Kristen A. Davenport1, Nicholas J. Haley2, Nathaniel
D. Denkers1, Candace K. Mathiason1 and Edward A. Hoover Jr1,3
+ Author Affiliations 1 Prion Research Center, Colorado State University,
USA; 2 Department of Diagnostic Medicine and Pathobiology, Kansas State
University, USA ↵3 E-mail: edward.hoover@colostate.edu Received 8 July 2014.
Accepted 6 October 2014.
Abstract
Prions are amyloid-forming proteins that cause transmissible spongiform
encephalopathies through a process involving the templated conversion of the
normal cellular prion protein (PrPC) to a pathogenic misfolded conformation.
Templated conversion has been modeled in several in vitro assays, including
serial protein misfolding amplification (sPMCA), amyloid seeding, and real time
quaking induced conversion (RT-QuIC). Because RT-QuIC measures formation of
amyloid fibrils in real time, it can be used to estimate the rate of seeded
conversion. Here we use samples from deer infected with chronic wasting disease
(CWD) in RT-QuIC to show that serial dilution of prion seed is linearly related
to the rate of amyloid formation over a range of 10-3 to 10-8 µg. We then used
an amyloid formation rate standard curve derived from a bioassayed reference
sample (CWD+ brain homogenate) to estimate the prion seed concentration and
infectivity in tissues, body fluids and excreta. Using these methods we estimate
that urine and saliva from CWD-infected deer contain between 1 and 5 LD50 per 10
ml, respectively. Thus, over the 1 to 2 year course of infection, a substantial
environmental reservoir of CWD prion contamination accumulates.
Amyloid Quantitation CWD Prion RT-QuIC TSE
P.141: Abundant prion shedding in CWD-infected deer revealed by Realtime
conversion
Edward A Hoover,1 Davin M Henderson,1 Nathaniel D Denkers,1 Candace K
Mathiason,1 Matteo Manca,2,3 and Byron Caughey2
1Prion Research Center, Colorado State University; Fort Collins, CO USA;
2Laboratory of Persistent Viral Diseases, NI AID; Hamilton, MT USA; 3Department
of Biomedical Sciences, University of Cagliari; Monserrato, Italy
Background/Introduction. Chronic wasting disease (CWD) is unique among
prion diseases in its efficient lateral transmission in nature. While the
presence of infectious prions in body fluids and excreta of infected cervids has
been demonstrated by bioassay, the dynamics, magnitude, and consequences of
prion shedding remain unknown. The present studies were undertaken to determine
the kinetics, duration, and magnitude of prion shedding in infected white-tailed
deer.
Materials and Methods. Longitudinal samples were collected from
white-tailed deer over a 2-year span after either oral (n=11)] aerosol (n = 6)
CWD exposure. The assay protocol employed phosphotungstic acid precipitation of
either whole saliva or the pelleted fraction of urine to seed recombinant Syrian
hamster prion PrP substrate in RT-QuIC reactions. Prion seeding activity was
assayed in 8 replicates of each sample employing thioflavin T detection in a
96-well plate-based fluorometer. Prion seeding reaction rate was determined by
taking the inverse of the time at which samples exceeded a threshold of 5
standard deviations above the mean fluorescence of negative controls (1/time to
threshold). Seeding activity was quantitated by comparing the realtime
conversion reaction rate to a standard curve derived from a reference bioassayed
brain pool homogenate from deer with terminal CWD.
Results. We analyzed >200 longitudinally collected, blinded, then
randomized saliva and urine samples from 17 CWDinfected and 3 uninfected
white-tailed deer. We detected prion shedding as early as 3 months post exposure
and sustained thereafter throughout the disease course in both aerosol and
orally exposed deer. The incidence of non-specific false positive results from
>500 saliva and urine samples from negative control deer was 0.8%. By
comparing real-time reaction rates for these body fluids to a bioassayed
serially diluted brain control, we estimated that ≤1 ml of saliva or urine from
pre-symptomatic infected deer constitutes a lethal infectious prion dose.
Conclusion. CWD prions are shed in saliva and urine of infected deer as
early as 3 months post infection and throughout the subsequent >1.5 year
course of infection. In current work we are examining the relationship of
prionemia to excretion and the impact of excreted prion binding to surfaces and
particulates in the environment.
Acknowledgments. Support: NIH-RO1-NS-061902; Morris Animal Foundation
D12ZO-045
P.154: Urinary shedding of prions in Chronic Wasting Disease infected
white-tailed deer
Nathaniel D Denkers,1 Davin M Henderson, 1 Candace K Mathiason,1 and Edward
A Hoover1 1Prion Research Center, Department of Microbiology, Immunology, and
Pathology, Colorado State University; Fort Collins, CO USA
Background/Introduction. Chronic wasting disease (CWD) is unique among
prion diseases in its efficient lateral transmission in nature, yet the dynamics
and magnitude of shedding and its immediate and long term consequences remain
unknown. The present study was designed to determine the frequency and time span
in which CWD prions are shed in urine from infected white-tailed deer using
adapted real-time quaking-induced conversion (RT-QuIC) methodology.
Materials and Methods. Longitudinal urine samples were collected by free
catch or catheterization over a 2-year period from oral-route infected [CWD+ (n
= 11)] and aerosol-route-infected [CWD+ (n = 6); CWD- (n = 3)] white-tailed
deer. High speed centrifugation pelleted material from 500 µl of urine was
treated with sodium phosphotungstic acid (Na-PTA), resuspended in 0.05% SDS
buffer, and used as seed in RT-QuIC assays employing recombinant Syrian hamster
prion PrP substrate. Eight (8) replicates of each sample were run and prion
seeding activity was recorded as thioflavin T binding fluorescence (480 nm
emission) using a fluorimeter-shaker. Samples were considered positive if they
crossed an established threshold (5 standard deviations above the negative mean
fluorescence).
Results. In our oral-route inoculation studies, prion seeding activity has
been demonstrated in urine collected at 6 months post-inoculation in 6 of 10
deer (11 of 80 replicates; 14%), and intermittently at later time points in all
11 CWD+ exposed deer. Our aerosol-route inoculation studies also showed prion
seeding activity in urine collected at 6 months post-inoculation in 1 of 2 deer
(3 of 16 replicates; 19%), and intermittently at later time points in 4 of 6
CWD+ exposed deer. Urine from sham-inoculated control deer and all baseline
samples yielded 3 false-positive prion seeding activities (3 of 352 replicates;
0.8%).
Conclusion. CWD prions (as inferred by prion seeding activity by RT-QuIC)
are shed in urine of infected deer as early as 6 months post inoculation and
throughout the subsequent disease course. Further studies are in progress
refining the real-time urinary prion assay sensitivity and we are examining more
closely the excretion time frame, magnitude, and sample variables in
relationship to inoculation route and prionemia in naturally and experimentally
CWD-infected cervids.
Acknowledgments. Support: NIH: RO1-NS-061902 and Morris Animal Foundation:
D12ZO-045
P.121: Efficient transmission of prion disease through environmental
contamination
Sandra Pritzkow, Rodrigo Morales, and Claudio Soto Mitchell Center for
Alzheimer’s disease and related Brain disorders; University of Texas Medical
School at Houston; Hourston, TX USA
Chronic wasting disease (CWD) is a prion disorder effecting captive and
free-ranging deer and elk. The efficient propagation suggests that horizontal
transmission through contaminated environment may play an important role. It has
been shown that infectious prions enter the environment through saliva, feces,
urine, blood or placenta tissue from infected animals, as well as by carcasses
from diseased animals and can stay infectious inside soil over several
years.
We hypothesize that environmental components getting in contact with
infectious prions can also play a role for the horizontal transmission of prion
diseases. To study this issue, surfaces composed of various environmentally
relevant materials were exposed to infectious prions and the attachment and
retention of infectious material was studied in vitro and in vivo. We analyzed
polypropylene, glass, stainless steel, wood, stone, aluminum, concrete and brass
surfaces exposed to 263K-infected brain homogenate. For in vitro analyses, the
material was incubated in serial dilutions of 263K-brain homogenate, washed
thoroughly and analyzed for the presence of PrPSc by PMCA. The results show that
even highly diluted PrPSc can bind efficiently to polypropylene, stainless
steel, glass, wood and stone and propagate the conversion of normal prion
protein. For in vivo experiments, hamsters were ic injected with implants
incubated in 1% 263K-infected brain homogenate. Hamsters, inoculated with
263K-contaminated implants of all groups, developed typical signs of prion
disease, whereas control animals inoculated with non-contaminated materials did
not.
In addition, in order to study the transmission in a more natural setting,
we exposed a group of hamster to habit in the presence of spheres composed of
various materials that were pretreated with 263K prions. Many of the hamsters
exposed to these contaminated materials developed typical signs of the disease
that were confirmed by immunohistological and biochemical analyses.
These findings suggest that various surfaces can efficiently bind
infectious prions and act as carriers of infectivity, suggesting that diverse
elements in the environment may play an important role in horizontal prion
transmission.
P.138: Phenotypic diversity in meadow vole (Microtus pennsylvanicus) prion
diseases following challenge with chronic wasting disease isolates
Christopher J Johnson,1 Christina M Carlson,1,2 Jay R Schneider,1 Jamie K
Wiepz,1 Crystal L Meyerett-Reid,3 Mark D Zabel,3 Joel A Pedersen,2 and Dennis M
Heisey1 1USGS National Wildlife Health Center; Madison, WI USA; 2University of
Wisconsin— Madison; Madison, WI USA; 3Colorado State University; Fort Collins,
CO USA
Chronic wasting disease (CWD), a prion disease of cervids (deer, elk and
moose), is spreading unchecked through large sections of North America.
Transmission of CWD among cervids is especially facile and can occur through
direct animal-toanimal contact and indirectly through contact with prions shed
from infected animals. The disease transmission threat posed by CWD to other
wildlife species remains unknown, but other species are inevitably exposed to
CWD by consumption of infectious materials and through contact with
environmental CWD contamination. In this study, we investigated the transmission
and adaptation of various white-tailed deer CWD isolates in the meadow vole
(Microtus pennsylvanicus), a native North American rodent that is sympatric with
current CWD epizootics that we have previously established is susceptible to
CWD. We found that serial subpassage of CWD from white-tailed deer homozygous
for glycine at position 96 (96GG) of the prion protein in meadow voles resulted
in the selection of a single prion strain that was characterized by homogeneity
in incubation period, abnormal prion protein (PrPTSE) glycoform ratio, lesion
profile and PrPTSE deposition pattern. In contrast, passage of CWD from
heterozygous 96GS genotype deer produced four unique disease phenotypes upon
first passage. Subpassage of these types ultimately resulted in selection of a
single strain by third passage that was distinct from the 96GG genotype
CWD-derived strain. We also establish that meadow voles are susceptible to CWD
via peripheral challenge, albeit with lower attack rates and longer incubation
periods. Interestingly, oral challenge of meadow voles with CWD resulted in
subclinical infection in primary passage animals, but manifested as clinical
prion disease upon subpassage. Our data establish that meadow voles are
permissive to CWD via peripheral exposure route, suggesting they could serve as
an environmental reservoir for CWD. Additionally, our data are consistent with
the hypothesis that at least two strains of CWD circulate in naturally-infected
cervid populations and provide evidence that meadow voles are a useful tool for
CWD strain typing.
P.146: Kinetics and cell association of chronic wasting disease prions shed
in saliva and urine of white-tailed deer
Nicholas J Haley,1,2 Scott Carver,3 Clare E Hoover,1 Kristen A Davenport,1
Candace K Mathiason,1 Glenn C Telling,1 and Edward A Hoover1
1Department of Microbiology, Immunology, and Pathology, College of
Veterinary Medicine and Biomedical Sciences; Colorado State University; Fort
Collins, CO USA; 2Department of Diagnostic Medicine and Pathobiology, College of
Veterinary Medicine; Kansas State University; Manhattan, KS USA; 3School of
Zoology; University of Tasmania; Hobart, Tasmania, Australia
Chronic wasting disease, a transmissible spongiform encephalopathy (TSE) of
deer, elk, and moose, is unique among prion diseases in its relatively efficient
horizontal transmissibility. Recent studies have shown that excreta—saliva,
urine, and feces—from CWD-positive cervids may play an important role in
horizontal transmission of CWD, and although the precise onset of shedding in
these excreta is unknown, it is thought to occur long before the onset of
clinical symptoms. High levels of prion seeding activity have been demonstrated
in excretory tissues of deer, including tongue, salivary glands, kidney, and
urinary bladder, though the origin(s) and cellular nature of infectious prions
in excreta is unknown. We hypothesized that excretory shedding of CWD prions in
saliva and urine would coincide with the appearance of PrPd appearance in
peripheral lymphatic tissues, and that infectivity would associate with cellular
preparations of these excreta. Following intracerebral inoculation of
susceptible Tg[CerPrP] mice, we observed efficient transmission in saliva
collected as early as 12 months post-exposure, coinciding with peripheral PrPd
appearance in tonsil biopsies; while urine collected at terminal disease was
only minimally infectious in transgenic mice. We also found that acellular
preparations of saliva, and cellular preparations of urine, were capable of
transmitting CWD infection to transgenic Tg[CerPrP] mice with incubation periods
similar to that of whole saliva or urine; saliva and urine from CWD-negative
deer failed to induce prion disease in these mice. Infectious titers were
determined for obex and bodily fluids, and were similar to those previously
described. These findings extend our understanding of CWD shedding in
white-tailed deer, and offer insight into the source and cellular associations
of infectious CWD prions in excreta.
P.178: Longitudinal quantitative analysis of CWD prions shed in saliva of
deer
Davin M Henderson, Nina Garbino, Nathaniel D Denkers, Amy V Nalls, Candace
K Mathiason, and Edward A Hoover Prion Research Center, College of Veterinary
Medicine and Biomedical Sciences, Colorado State University; Fort Collins, CO
USA
Background/Introduction. Chronic Wasting Disease (CWD) is an emergent
rapidly spreading fatal prion disease of cervids (deer, elk and moose). CWD has
now been identified in 22 States (including two new states within the last
year), 2 Canadian provinces, and South Korea. Shedding of infectious prions in
excreta (saliva, urine, feces) may be an important factor in CWD transmission.
Here we apply an adapted version of a rapid in vitro assay [real-time
quaking-induced conversion (RT-QuIC)] to determine the time of onset, length,
pattern, and magnitude of prion shedding in saliva of infected deer.
Materials and Methods. The RT-QuIC assay was performed as previously
described in Henderson et al. PLoS-One (2013). Saliva samples were quantitated
by comparison to a RT-QuIC reaction rate standard curve of a bioassayed obex
sample from a terminally ill cervid.
Results. To better understand the onset and length of CWD prion shedding we
analyzed >150 longitudinally collected, blinded, then randomized saliva
samples from 17 CWD-infected and 3 uninfected white-tailed deer. We observed
prion shedding, as detected by the RT-QuIC assay, as early as 3 months from
inoculation and sustained shedding throughout the disease course in both aerosol
and orally exposed deer. We estimated the infectious lethal dose of prions shed
in saliva from infected deer by comparing real-time reaction rates of saliva
samples to a bioassayed serially diluted brain control. Our results indicate
that as little as 1 ml of saliva from pre-symptomatic infected deer constitutes
a lethal CWD prion dose.
Conclusions. During the pre-symptomatic stage of CWD infection and
throughout the course of disease deer may be shedding multiple LD50 doses per
day in their saliva. CWD prion shedding through saliva and excreta may account
for the unprecedented spread of this prion disease in nature. Acknowledgments.
Supported by NIH grant RO1-NS-061902 and grant D12ZO-045 from the Morris Animal
Foundation.
*** We conclude that TSE infectivity is likely to survive burial for long
time periods with minimal loss of infectivity and limited movement from the
original burial site. However PMCA results have shown that there is the
potential for rainwater to elute TSE related material from soil which could lead
to the contamination of a wider area. These experiments reinforce the importance
of risk assessment when disposing of TSE risk materials.
*** The results show that even highly diluted PrPSc can bind efficiently to
polypropylene, stainless steel, glass, wood and stone and propagate the
conversion of normal prion protein. For in vivo experiments, hamsters were ic
injected with implants incubated in 1% 263K-infected brain homogenate. Hamsters,
inoculated with 263K-contaminated implants of all groups, developed typical
signs of prion disease, whereas control animals inoculated with non-contaminated
materials did not.
PRION 2014 CONFERENCE
CHRONIC WASTING DISEASE CWD
A FEW FINDINGS ;
Conclusions. To our knowledge, this is the first established experimental
model of CWD in TgSB3985. We found evidence for co-existence or divergence of
two CWD strains adapted to Tga20 mice and their replication in TgSB3985 mice.
Finally, we observed phenotypic differences between cervid-derived CWD and
CWD/Tg20 strains upon propagation in TgSB3985 mice. Further studies are underway
to characterize these strains.
We conclude that TSE infectivity is likely to survive burial for long time
periods with minimal loss of infectivity and limited movement from the original
burial site. However PMCA results have shown that there is the potential for
rainwater to elute TSE related material from soil which could lead to the
contamination of a wider area. These experiments reinforce the importance of
risk assessment when disposing of TSE risk materials.
The results show that even highly diluted PrPSc can bind efficiently to
polypropylene, stainless steel, glass, wood and stone and propagate the
conversion of normal prion protein. For in vivo experiments, hamsters were ic
injected with implants incubated in 1% 263K-infected brain homogenate. Hamsters,
inoculated with 263K-contaminated implants of all groups, developed typical
signs of prion disease, whereas control animals inoculated with non-contaminated
materials did not.
Our data establish that meadow voles are permissive to CWD via peripheral
exposure route, suggesting they could serve as an environmental reservoir for
CWD. Additionally, our data are consistent with the hypothesis that at least two
strains of CWD circulate in naturally-infected cervid populations and provide
evidence that meadow voles are a useful tool for CWD strain typing.
Conclusion. CWD prions are shed in saliva and urine of infected deer as
early as 3 months post infection and throughout the subsequent >1.5 year
course of infection. In current work we are examining the relationship of
prionemia to excretion and the impact of excreted prion binding to surfaces and
particulates in the environment.
Conclusion. CWD prions (as inferred by prion seeding activity by RT-QuIC)
are shed in urine of infected deer as early as 6 months post inoculation and
throughout the subsequent disease course. Further studies are in progress
refining the real-time urinary prion assay sensitivity and we are examining more
closely the excretion time frame, magnitude, and sample variables in
relationship to inoculation route and prionemia in naturally and experimentally
CWD-infected cervids.
Conclusions. Our results suggested that the odds of infection for CWD is
likely controlled by areas that congregate deer thus increasing direct
transmission (deer-to-deer interactions) or indirect transmission
(deer-to-environment) by sharing or depositing infectious prion proteins in
these preferred habitats. Epidemiology of CWD in the eastern U.S. is likely
controlled by separate factors than found in the Midwestern and endemic areas
for CWD and can assist in performing more efficient surveillance efforts for the
region.
Conclusions. During the pre-symptomatic stage of CWD infection and
throughout the course of disease deer may be shedding multiple LD50 doses per
day in their saliva. CWD prion shedding through saliva and excreta may account
for the unprecedented spread of this prion disease in nature.
see full text and more ;
Monday, June 23, 2014
*** PRION 2014 CONFERENCE CHRONIC WASTING DISEASE CWD
*** Infectious agent of sheep scrapie may persist in the environment for at
least 16 years***
Gudmundur Georgsson1, Sigurdur Sigurdarson2 and Paul Brown3
New studies on the heat resistance of hamster-adapted scrapie agent:
Threshold survival after ashing at 600°C suggests an inorganic template of
replication
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel
Production
Detection of protease-resistant cervid prion protein in water from a
CWD-endemic area
A Quantitative Assessment of the Amount of Prion Diverted to Category 1
Materials and Wastewater During Processing
Rapid assessment of bovine spongiform encephalopathy prion inactivation by
heat treatment in yellow grease produced in the industrial manufacturing process
of meat and bone meals
spreading cwd around...tss
Between 1996 and 2002, chronic wasting disease was diagnosed in 39 herds of
farmed elk in Saskatchewan in a single epidemic. All of these herds were
depopulated as part of the Canadian Food Inspection Agency’s (CFIA) disease
eradication program. Animals, primarily over 12 mo of age, were tested for the
presence CWD prions following euthanasia. Twenty-one of the herds were linked
through movements of live animals with latent CWD from a single infected source
herd in Saskatchewan, 17 through movements of animals from 7 of the secondarily
infected herds.
***The source herd is believed to have become infected via importation of
animals from a game farm in South Dakota where CWD was subsequently diagnosed
(7,4). A wide range in herd prevalence of CWD at the time of herd depopulation
of these herds was observed. Within-herd transmission was observed on some
farms, while the disease remained confined to the introduced animals on other
farms.
spreading cwd around...tss
Friday, May 13, 2011
Chronic Wasting Disease (CWD) outbreaks and surveillance program in the
Republic of Korea Chronic Wasting Disease (CWD) outbreaks and surveillance
program in the Republic of Korea
Hyun-Joo Sohn, Yoon-Hee Lee, Min-jeong Kim, Eun-Im Yun, Hyo-Jin Kim,
Won-Yong Lee, Dong-Seob Tark, In- Soo Cho, Foreign Animal Disease Research
Division, National Veterinary Research and Quarantine Service, Republic of Korea
Chronic wasting disease (CWD) has been recognized as an important prion
disease in native North America deer and Rocky mountain elks. The disease is a
unique member of the transmissible spongiform encephalopathies (TSEs), which
naturally affects only a few species. CWD had been limited to USA and Canada
until 2000.
On 28 December 2000, information from the Canadian government showed that a
total of 95 elk had been exported from farms with CWD to Korea. These consisted
of 23 elk in 1994 originating from the so-called “source farm” in Canada, and 72
elk in 1997, which had been held in pre export quarantine at the “source
farm”.Based on export information of CWD suspected elk from Canada to Korea, CWD
surveillance program was initiated by the Ministry of Agriculture and Forestry
(MAF) in 2001.
All elks imported in 1997 were traced back, however elks imported in 1994
were impossible to identify. CWD control measures included stamping out of all
animals in the affected farm, and thorough cleaning and disinfection of the
premises. In addition, nationwide clinical surveillance of Korean native
cervids, and improved measures to ensure reporting of CWD suspect cases were
implemented.
Total of 9 elks were found to be affected. CWD was designated as a
notifiable disease under the Act for Prevention of Livestock Epidemics in 2002.
Additional CWD cases - 12 elks and 2 elks - were diagnosed in 2004 and
2005.
Since February of 2005, when slaughtered elks were found to be positive,
all slaughtered cervid for human consumption at abattoirs were designated as
target of the CWD surveillance program. Currently, CWD laboratory testing is
only conducted by National Reference Laboratory on CWD, which is the Foreign
Animal Disease Division (FADD) of National Veterinary Research and Quarantine
Service (NVRQS).
In July 2010, one out of 3 elks from Farm 1 which were slaughtered for the
human consumption was confirmed as positive. Consequently, all cervid – 54 elks,
41 Sika deer and 5 Albino deer – were culled and one elk was found to be
positive. Epidemiological investigations were conducted by Veterinary
Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary
services.
Epidemiologically related farms were found as 3 farms and all cervid at
these farms were culled and subjected to CWD diagnosis. Three elks and 5
crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2.
All cervids at Farm 3 and Farm 4 – 15 elks and 47 elks – were culled and
confirmed as negative.
Further epidemiological investigations showed that these CWD outbreaks were
linked to the importation of elks from Canada in 1994 based on circumstantial
evidences.
In December 2010, one elk was confirmed as positive at Farm 5.
Consequently, all cervid – 3 elks, 11 Manchurian Sika deer and 20 Sika deer –
were culled and one Manchurian Sika deer and seven Sika deer were found to be
positive. This is the first report of CWD in these sub-species of deer.
Epidemiological investigations found that the owner of the Farm 2 in CWD
outbreaks in July 2010 had co-owned the Farm 5.
In addition, it was newly revealed that one positive elk was introduced
from Farm 6 of Jinju-si Gyeongsang Namdo. All cervid – 19 elks, 15 crossbreed
(species unknown) and 64 Sika deer – of Farm 6 were culled, but all confirmed as
negative.
: Corresponding author: Dr. Hyun-Joo Sohn (+82-31-467-1867, E-mail:
shonhj@korea.kr) 2011 Pre-congress Workshop: TSEs in animals and their
environment 5
***raising the possibility that deer may be susceptible to multiple scrapie
strains. ***
Saturday, August 02, 2014
Structural effects of PrP polymorphisms on intra- and inter-species prion
transmission
*** Finally, our findings showing that Tg(DeerPrP), but not Tg(ElkPrP) are
sensitive to infection with SSBP/1 belie previously published results showing
that SSBP/1 of the same provenance caused disease in two lines of Tg mice
expressing elk PrP (13). However, our results appear to be consistent with the
reported susceptibilities of elk and deer to sheep prions. In previous studies,
of six elk inoculated with scrapie, three presented with neurological signs and
neuropathology, but only after long and variable times to disease onset ranging
from 25 to 46 months (29). In contrast, our results with SSBP/1 demonstrate
relatively facile transmission of scrapie to deer, with all inoculated animals
developing within 19 to 20 months, which is in accordance with susceptibility of
deer to a US scrapie isolate with a similar time to disease onset (24).
Polymorphisms ovine PrP add a further level of complexity, since they control
the propagation scrapie strains. Occupancy of residue 136 by A or V is of
particular importance. Our previous results indicated that SSBP/1 is comprised
of a dominant strain that is preferentially propagated by sheep PrP encoding V
at 136 (12). In contrast, the scrapie prions used in the deer transmission
studies of Greenlee and colleagues were isolated from a sheep encoding A136,
***raising the possibility that deer may be susceptible to multiple scrapie
strains. ***
Significance
The unpredictable recurrences of prion epidemics, their incurable
lethality, and the capacity of animal prions to infect humans, provide
significant motivation to ascertain the parameters governing disease
transmission. The unprecedented spread, and uncertain zoonotic potential of
chronic wasting disease (CWD), a contagious epidemic among deer, elk, and other
cervids, is of particular concern. Here we demonstrate that naturally occurring
primary structural differences in cervid PrPs differentially impact the
efficiency of intra- and interspecies prion transmission. Our results not only
deliver new information about the role of primary structural variation on prion
susceptibility, but also provide functional support to a mechanism in which
plasticity of a tertiary structural epitope governs prion protein conversion and
intra- and inter-species susceptibility to prions.-
snip...
Saturday, August 02, 2014
Structural effects of PrP polymorphisms on intra- and inter-species prion
transmission
Thursday, November 21, 2013
*** Assessing the susceptibility of transgenic mice over-expressing deer
prion protein to bovine spongiform encephalopathy
The present study was designed to assess the susceptibility of the
prototypic mouse line, Tg(CerPrP)1536+/- to bovine spongiform encephalopathy
(BSE) prions, which have the ability to overcome species barriers.
Tg(CerPrP)1536+/- mice challenged with red deer-adapted BSE resulted in a
90-100% attack rates, BSE from cattle failed to transmit, indicating agent
adaptation in the deer.
Tuesday, October 07, 2014
Wisconsin white-tailed deer tested positive for CWD on a Richland County
breeding farm, and a case of CWD has been discovered on a Marathon County
hunting preserve
Thursday, October 02, 2014
IOWA TEST RESULTS FROM CAPTIVE DEER HERD WITH CHRONIC WASTING DISEASE
RELEASED 79.8 percent of the deer tested positive for the disease
Thursday, July 03, 2014
*** How Chronic Wasting Disease is affecting deer population and what’s the
risk to humans and pets?
Tuesday, July 01, 2014
*** CHRONIC WASTING DISEASE CWD TSE PRION DISEASE, GAME FARMS, AND
POTENTIAL RISK FACTORS THERE FROM
Sunday, September 21, 2014
INFORM: Cervid Health and States Indemnity FY 2015
TSS
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