Assessing Transmissible Spongiform Encephalopathy Species Barriers with an
In Vitro Prion Protein Conversion Assay
Christopher J. Johnson1, Christina M. Carlson2, Aaron R. Morawski3, Alyson
Manthei4, Neil R. Cashman5
1USGS National Wildlife Health Center, 2Department of Soil Science,
University of Wisconsin–Madison, 3Laboratory of Immunology, National Institute
of Allergy and Infectious Diseases, National Institutes of Health, 4Merial
Veterinary Scholars Program, School of Veterinary Medicine, University of
Wisconsin–Madison, 5Department of Neurology, University of British Columbia
Summary
Measuring the barrier to the interspecies transmission of prion diseases is
challenging and typically involves animal challenges or biochemical assays.
Here, we present an in vitro prion protein conversion assay with the ability to
predict species barriers.
Date Published: 3/10/2015, Issue 97; doi: 10.3791/52522
Keywords: Medicine, Issue 97, Prion, species barrier, conversion,
immunoblotting, transmissible spongiform encephalopathy, interspecies
transmission Cite this Article
Johnson, C. J., Carlson, C. M., Morawski, A. R., Manthei, A., Cashman, N.
R. Assessing Transmissible Spongiform Encephalopathy Species Barriers with an In
Vitro Prion Protein Conversion Assay. J. Vis. Exp. (97), e52522,
doi:10.3791/52522 (2015). Abstract
Studies to understanding interspecies transmission of transmissible
spongiform encephalopathies (TSEs, prion diseases) are challenging in that they
typically rely upon lengthy and costly in vivo animal challenge studies. A
number of in vitro assays have been developed to aid in measuring prion species
barriers, thereby reducing animal use and providing quicker results than animal
bioassays. Here, we present the protocol for a rapid in vitro prion conversion
assay called the conversion efficiency ratio (CER) assay. In this assay cellular
prion protein (PrPC) from an uninfected host brain is denatured at both pH 7.4
and 3.5 to produce two substrates. When the pH 7.4 substrate is incubated with
TSE agent, the amount of PrPC that converts to a proteinase K (PK)-resistant
state is modulated by the original host’s species barrier to the TSE agent. In
contrast, PrPC in the pH 3.5 substrate is misfolded by any TSE agent. By
comparing the amount of PK-resistant prion protein in the two substrates, an
assessment of the host’s species barrier can be made. We show that the CER assay
correctly predicts known prion species barriers of laboratory mice and, as an
example, show some preliminary results suggesting that bobcats (Lynx rufus) may
be susceptible to white-tailed deer (Odocoileus virginianus) chronic wasting
disease agent.
>>> show some preliminary results suggesting that bobcats (Lynx
rufus) may be susceptible to white-tailed deer (Odocoileus virginianus) chronic
wasting disease agent.
AD.63: Susceptibility of domestic cats to chronic wasting disease
Amy V.Nalls,1 Candace Mathiason,1 Davis Seelig,2 Susan Kraft,1 Kevin
Carnes,1 Kelly Anderson,1 Jeanette Hayes-Klug1 and Edward A. Hoover1
1Colorado State University; Fort Collins, CO USA; 2University of Minnesota;
Saint Paul, MN USA
Domestic and nondomestic cats have been shown to be susceptible to feline
spongiform encephalopathy (FSE), almost certainly caused by consumption of
bovine spongiform encephalopathy (BSE)-contaminated meat. Because domestic and
free-ranging nondomestic felids scavenge cervid carcasses, including those in
areas affected by chronic wasting disease (CWD), we evaluated the susceptibility
of the domestic cat (Felis catus) to CWD infection experimentally. Cohorts of 5
cats each were inoculated either intracerebrally (IC) or orally (PO) with
CWD-infected deer brain. At 40 and 42 mo post-inoculation, two IC-inoculated
cats developed signs consistent with prion disease, including a stilted gait,
weight loss, anorexia, polydipsia, patterned motor behaviors, head and tail
tremors, and ataxia, and progressed to terminal disease within 5 mo. Brains from
these two cats were pooled and inoculated into cohorts of cats by IC, PO, and
intraperitoneal and subcutaneous (IP/SC) routes. Upon subpassage, feline-adapted
CWD (FelCWD) was transmitted to all IC-inoculated cats with a decreased
incubation period of 23 to 27 mo. FelCWD was detected in the brains of all the
symptomatic cats by western blotting and immunohistochemistry and abnormalities
were seen in magnetic resonance imaging, including multifocal T2 fluid
attenuated inversion recovery (FLAIR) signal hyper-intensities, ventricular size
increases, prominent sulci, and white matter tract cavitation. Currently, 3 of 4
IP/SQ and 2 of 4 PO inoculared cats have developed abnormal behavior patterns
consistent with the early stage of feline CWD. These results demonstrate that
CWD can be transmitted and adapted to the domestic cat, thus raising the issue
of potential cervid-to- feline transmission in nature.
www.landesbioscience.com
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
Monday, August 8, 2011
Susceptibility of Domestic Cats to CWD Infection
Sunday, August 25, 2013
Prion2013 Chronic Wasting Disease CWD risk factors, humans, domestic cats,
blood, and mother to offspring transmission
Feline Spongiform Encephalopathy (FSE) FSE was first identified in the UK
in 1990. Most cases have been reported in the UK, where the epidemic has been
consistent with that of the BSE epidemic. Some other countries (e.g. Norway,
Liechtenstein and France) have also reported cases.
Most cases have been reported in domestic cats but there have also been
cases in captive exotic cats (e.g. Cheetah, Lion, Asian leopard cat, Ocelot,
Puma and Tiger). The disease is characterised by progressive nervous signs,
including ataxia, hyper-reactivity and behavioural changes and is fatal.
The chemical and biological properties of the infectious agent are
identical to those of the BSE and vCJD agents. These findings support the
hypothesis that the FSE epidemic resulted from the consumption of food
contaminated with the BSE agent.
The FSE epidemic has declined as a result of tight controls on the disposal
of specified risk material and other animal by-products.
References: Leggett, M.M. et al.(1990) A spongiform encephalopathy in a
cat. Veterinary Record. 127. 586-588
Synge, B.A. et al. (1991) Spongiform encephalopathy in a Scottish cat.
Veterinary Record. 129. 320
Wyatt, J. M. et al. (1991) Naturally occurring scrapie-like spongiform
encephalopathy in five domestic cats. Veterinary Record. 129. 233.
Gruffydd-Jones, T. J.et al.. (1991) Feline spongiform encephalopathy. J.
Small Animal Practice. 33. 471-476.
Pearson, G. R. et al. (1992) Feline spongiform encephalopathy: fibril and
PrP studies. Veterinary Record. 131. 307-310.
Willoughby, K. et al. (1992) Spongiform encephalopathy in a captive puma
(Felis concolor). Veterinary Record. 131. 431-434.
Fraser, H. et al. (1994) Transmission of feline spongiform encephalopathy
to mice. Veterinary Record 134. 449.
Bratberg, B. et al. (1995) Feline spongiform encephalopathy in a cat in
Norway. Veterinary Record 136. 444
Baron, T. et al. (1997) Spongiform encephalopathy in an imported cheetah in
France. Veterinary Record 141. 270-271
Zanusso, G et al. (1998) Simultaneous occurrence of spongiform
encephalopathy in a man and his cat in Italy. Lancet, V352, N9134, OCT 3, Pp
1116-1117.
Ryder, S.J. et al. (2001) Inconsistent detection of PrP in extraneural
tissues of cats with feline spongiform encephalopathy. Veterinary Record 146.
437-441
Kelly, D.F. et al. (2005) Neuropathological findings in cats with
clinically suspect but histologically unconfirmed feline spongiform
encephalopathy. Veterinary Record 156. 472-477.
3 further cheetah cases have occured, plus 1 lion, plus all the primates,
and 20 additional house cats. Nothing has been published on any of these UK
cases either. One supposes the problem here with publishing is that many
unpublished cases were _born_ long after the feed "ban". Caught between a rock
and a hard place: leaky ban or horizontal transmission (or both).
YOU explained that imported crushed heads were extensively used in the
petfood industry...
http://web.archive.org/web/20060303042720/http://www.bseinquiry.gov.uk/files/yb/1989/04/14001001.pdf
In particular I do not believe one can say that the levels of the scrapie
agent in pet food are so low that domestic animals are not exposed...
http://web.archive.org/web/20040301231838/http://www.bseinquiry.gov.uk/files/yb/1989/04/24003001.pdf
http://web.archive.org/web/20060303042732/http://www.bseinquiry.gov.uk/files/yb/1989/04/25001001.pdf
on occassions, materials obtained from slaughterhouses will be derived from
sheep affected with scrapie or cattle that may be incubating BSE for use in
petfood manufacture...
http://web.archive.org/web/20060303042739/http://www.bseinquiry.gov.uk/files/yb/1989/05/03007001.pdf
*** Meldrum's notes on pet foods and materials used
http://web.archive.org/web/20060303042745/http://www.bseinquiry.gov.uk/files/yb/1989/05/16001001.pdf
*** BSE & Pedigree Petfoods ***
http://web.archive.org/web/20060303042725/http://www.bseinquiry.gov.uk/files/yb/1989/05/16002001.pdf
In 2003, Denver Post reporter Theo Stein interviewed scientists about CWD
spreading though deer and elk in Colorado. Dr. Valerius Geist, who paradoxically
has become a darling of anti-wolfers, made this assertion about the significance
of wolves in containing CWD spread via proteins called prions.
“Wolves will certainly bring the disease to a halt,” he said. “They will
remove infected individuals and clean up carcasses that could transmit the
disease.”
Stein added that “Geist and Princeton University biologist Andrew Dobson
theorize that killing off the wolf allowed CWD to take hold in the first
place.”
Wolves aren’t alone. In a 2009 study titled “Mountain lions prey
selectively on prion-infected mule deer,” researchers in Colorado discovered
that “adult mule deer killed by mountain lions were more likely to be
prion-infected than were deer killed more randomly … suggesting that mountain
lions were selecting for infected individuals when they targeted adult
deer.”
NO, NO, NOT NO, BUT HELL KNOW !!!
PLEASE be careful what you ask for.
recently, canine spongiform encephalopathy has been confirmed.
I proved this in 2005, with a letter from MAFF/DEFRA et al confirming my
suspicions of the ‘hound study’ way back. this was covered up. see documents
below.
also, recently, cwd to the domestic cat is a great concern.
even though to date, as far as I am aware of, the cwd study on the mountain
lion has not produced any confirmation yet, we already know that the feline
species is highly succeptible to the TSE prion. domestic cats and the exotic zoo
big cats.
so in my honest opinion, any program that would use wild animals to prey on
other wild animals, as a tool to help curb CWD TSE prion disease, would only
help enhance the spread of disease, and it would only help spread the disease to
other species. ...TSS
Monday, February 14, 2011
THE ROLE OF PREDATION IN DISEASE CONTROL: A COMPARISON OF SELECTIVE AND
NONSELECTIVE REMOVAL ON PRION DISEASE DYNAMICS IN DEER
NO, NO, NOT NO, BUT HELL NO !
Journal of Wildlife Diseases, 47(1), 2011, pp. 78-93 © Wildlife Disease
Association 2011
OR-09: Canine spongiform encephalopathy—A new form of animal prion disease
Monique David, Mourad Tayebi UT Health; Houston, TX USA
It was also hypothesized that BSE might have originated from an
unrecognized sporadic or genetic case of bovine prion disease incorporated into
cattle feed or even cattle feed contaminated with prion-infected human remains.1
However, strong support for a genetic origin of BSE has recently been
demonstrated in an H-type BSE case exhibiting the novel mutation E211K.2
Furthermore, a specific prion protein strain causing BSE in cattle is believed
to be the etiological agent responsible for the novel human prion disease,
variant Creutzfeldt-Jakob disease (vCJD).3 Cases of vCJD have been identified in
a number countries, including France, Italy, Ireland, the Netherlands, Canada,
Japan, US and the UK with the largest number of cases. Naturally occurring
feline spongiform encephalopathy of domestic cats4 and spongiform
encephalopathies of a number of zoo animals so-called exotic ungulate
encephalopathies5,6 are also recognized as animal prion diseases, and are
thought to have resulted from the same BSE-contaminated food given to cattle and
humans, although and at least in some of these cases, a sporadic and/or genetic
etiology cannot be ruled out. The canine species seems to display resistance to
prion disease and no single case has so far been reported.7,8 Here, we describe
a case of a 9 week old male Rottweiler puppy presenting neurological deficits;
and histological examination revealed spongiform vacuolation characteristic of
those associated with prion diseases.9 Initial biochemical studies using
anti-PrP antibodies revealed the presence of partially proteinase K-resistant
fragment by western blotting. Furthermore, immunohistochemistry revealed
spongiform degeneration consistent with those found in prion disease and
displayed staining for PrPSc in the cortex.
Of major importance, PrPSc isolated from the Rottweiler was able to cross
the species barrier transmitted to hamster in vitro with PMCA and in vivo (one
hamster out of 5). Futhermore, second in vivo passage to hamsters, led to 100%
attack rate (n = 4) and animals displayed untypical lesional profile and shorter
incubation period.
In this study, we show that the canine species might be sensitive to prion
disease and that PrPSc isolated from a dog can be transmitted to dogs and
hamsters in vitro using PMCA and in vivo to hamsters.
If our preliminary results are confirmed, the proposal will have a major
impact on animal and public health and would certainly lead to implementing new
control measures for ‘canine spongiform encephalopathy’ (CSE).
References 1. Colchester AC, Colchester NT. The origin of bovine spongiform
encephalopathy: the human prion disease hypothesis. Lancet 2005; 366:856-61;
PMID:16139661; http://
dx.doi.org/10.1016/S0140-6736(05)67218-2.
2. Richt JA, Hall SM. BSE case associated with prion protein gene mutation.
PLoS Pathog 2008; 4:e1000156; PMID:18787697; http://dx.doi.org/10.1371/journal.
ppat.1000156.
3. Collinge J. Human prion diseases and bovine spongiform encephalopathy
(BSE). Hum Mol Genet 1997; 6:1699-705; PMID:9300662; http://dx.doi.org/10.1093/
hmg/6.10.1699.
4. Wyatt JM, Pearson GR, Smerdon TN, Gruffydd-Jones TJ, Wells GA, Wilesmith
JW. Naturally occurring scrapie-like spongiform encephalopathy in five domestic
cats. Vet Rec 1991; 129:233-6; PMID:1957458; http://dx.doi.org/10.1136/vr.129.11.233.
5. Jeffrey M, Wells GA. Spongiform encephalopathy in a nyala (Tragelaphus
angasi). Vet Pathol 1988; 25:398-9; PMID:3232315; http://dx.doi.org/10.1177/030098588802500514.
6. Kirkwood JK, Wells GA, Wilesmith JW, Cunningham AA, Jackson SI.
Spongiform encephalopathy in an arabian oryx (Oryx leucoryx) and a greater kudu
(Tragelaphus strepsiceros). Vet Rec 1990; 127:418-20; PMID:2264242.
7. Bartz JC, McKenzie DI, Bessen RA, Marsh RF, Aiken JM. Transmissible mink
encephalopathy species barrier effect between ferret and mink: PrP gene and
protein analysis. J Gen Virol 1994; 75:2947-53; PMID:7964604; http://dx.doi.org/10.1099/0022-1317-
75-11-2947.
8. Lysek DA, Schorn C, Nivon LG, Esteve-Moya V, Christen B, Calzolai L, et
al. Prion protein NMR structures of cats, dogs, pigs, and sheep. Proc Natl Acad
Sci U S A 2005; 102:640-5; PMID:15647367; http://dx.doi.org/10.1073/pnas.0408937102.
9. Budka H. Neuropathology of prion diseases. Br Med Bull 2003; 66:121-30;
PMID:14522854; http://dx.doi.org/10.1093/bmb/66.1.121.
Monday, March 26, 2012
CANINE SPONGIFORM ENCEPHALOPATHY: A NEW FORM OF ANIMAL PRION DISEASE
http://caninespongiformencephalopathy.blogspot.com/2012/03/canine-spongiform-encephalopathy-new.html
Monday, March 8, 2010
Canine Spongiform Encephalopathy aka MAD DOG DISEASE
=======================================
2013
Strain characteristics of the in vitro-adapted rabbit and dog BSE agent
remained invariable with respect to the original cattle BSE prion, suggesting
that the naturally low susceptibility of rabbits and dogs to prion infections
should not alter their zoonotic potential if these animals became infected with
BSE.
=======================================
Neurobiology of Disease
Bovine Spongiform Encephalopathy Induces Misfolding of Alleged
Prion-Resistant Species Cellular Prion Protein without Altering Its
Pathobiological Features
Enric Vidal3, Natalia Fernández-Borges1, Belén Pintado4, Montserrat
Ordóñez3, Mercedes Márquez6, Dolors Fondevila5,6, Juan María Torres7, Martí
Pumarola5,6, and Joaquín Castilla1,2 + Author Affiliations
1CIC bioGUNE, 48160 Derio, Bizkaia, Spain,
2IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Bizkaia, Spain,
3Centre de Recerca en Sanitat Animal, Campus de la Universitat Autònoma de
Barcelona (UAB)-IRTA, 08193 Bellaterra, Barcelona, Spain,
4Centro Nacional de Biotecnología, Campus de Cantoblanco, 28049
Cantoblanco, Madrid, Spain,
5Department of Animal Medicine and Surgery, Veterinary Faculty, UAB, 08193
Bellaterra (Cerdanyola del Vallès), Barcelona, Spain,
6Murine Pathology Unit, Centre de Biotecnologia Animal i Teràpia Gènica,
UAB, 08193 Bellaterra (Cerdanyola del Vallès), Barcelona, Spain, and
7Centro de Investigación en Sanidad Animal-Instituto Nacional de
Investigación y Tecnología Agraria y Alimentaria, 28130 Valdeolmos, Madrid,
Spain
Author contributions: E.V., N.F.-B., and J.C. designed research; E.V.,
N.F.-B., B.P., M.O., M.M., D.F., and J.C. performed research; E.V., N.F.-B.,
B.P., and J.C. contributed unpublished reagents/analytic tools; E.V., N.F.-B.,
B.P., M.O., M.M., D.F., J.M.T., M.P., and J.C. analyzed data; E.V. and J.C.
wrote the paper.
Abstract
Bovine spongiform encephalopathy (BSE) prions were responsible for an
unforeseen epizootic in cattle which had a vast social, economic, and public
health impact. This was primarily because BSE prions were found to be
transmissible to humans. Other species were also susceptible to BSE either by
natural infection (e.g., felids, caprids) or in experimental settings (e.g.,
sheep, mice). However, certain species closely related to humans, such as canids
and leporids, were apparently resistant to BSE. In vitro prion amplification
techniques (saPMCA) were used to successfully misfold the cellular prion protein
(PrPc) of these allegedly resistant species into a BSE-type prion protein. The
biochemical and biological properties of the new prions generated in vitro after
seeding rabbit and dog brain homogenates with classical BSE were studied.
Pathobiological features of the resultant prion strains were determined after
their inoculation into transgenic mice expressing bovine and human PrPC. Strain
characteristics of the in vitro-adapted rabbit and dog BSE agent remained
invariable with respect to the original cattle BSE prion, suggesting that the
naturally low susceptibility of rabbits and dogs to prion infections should not
alter their zoonotic potential if these animals became infected with BSE. This
study provides a sound basis for risk assessment regarding prion diseases in
purportedly resistant species.
Received January 18, 2013. Revision received March 7, 2013. Accepted March
23, 2013. Copyright © 2013 the authors 0270-6474/13/337778-09$15.00/0
2005
DEFRA Department for Environment, Food & Rural Affairs
Area 307, London, SW1P 4PQ Telephone: 0207 904 6000 Direct line: 0207 904
6287 E-mail: h.mcdonagh.defra.gsi.gov.uk
GTN: FAX:
Mr T S Singeltary P.O. Box 42 Bacliff Texas USA 77518
21 November 2001
Dear Mr Singeltary
TSE IN HOUNDS
Thank you for e-mail regarding the hounds survey. I am sorry for the long
delay in responding.
As you note, the hound survey remains unpublished. However the Spongiform
Encephalopathy Advisory Committee (SEAC), the UK Government's independent
Advisory Committee on all aspects related to BSE-like disease, gave the hound
study detailed consideration at their meeting in January 1994. As a summary of
this meeting published in the BSE inquiry noted, the Committee were clearly
concerned about the work that had been carried out, concluding that there had
clearly been problems with it, particularly the control on the histology, and
that it was more or less inconclusive. However was agreed that there should be a
re-evaluation of the pathological material in the study.
Later, at their meeting in June 95, The Committee re-evaluated the hound
study to see if any useful results could be gained from it. The Chairman
concluded that there were varying opinions within the Committee on further work.
It did not suggest any further transmission studies and thought that the lack of
clinical data was a major weakness.
Overall, it is clear that SEAC had major concerns about the survey as
conducted. As a result it is likely that the authors felt that it would not
stand up to r~eer review and hence it was never published. As noted above, and
in the detailed minutes of the SEAC meeting in June 95, SEAC considered whether
additional work should be performed to examine dogs for evidence of TSE
infection. Although the Committee had mixed views about the merits of conducting
further work, the Chairman noted that when the Southwood Committee made their
recommendation to complete an assessment of possible spongiform disease in dogs,
no TSEs had been identified in other species and hence dogs were perceived as a
high risk population and worthy of study. However subsequent to the original
recommendation, made in 1990, a number of other species had been identified with
TSE ( e.g. cats) so a study in hounds was less
critical. For more details see- http://www.bseinquiry.gov.uk/files/yb/1995/06/21005001.pdf
As this study remains unpublished, my understanding is that the ownership
of the data essentially remains with the original researchers. Thus
unfortunately, I am unable to help with your request to supply information on
the hound survey directly. My only suggestion is that you contact one of the
researchers originally involved in the project, such as Gerald Wells. He can be
contacted at the following address.
Dr Gerald Wells, Veterinary Laboratories Agency, New Haw, Addlestone,
Surrey, KT 15 3NB, UK
You may also wish to be aware that since November 1994 all suspected cases
of spongiform encephalopathy in animals and poultry were made notifiable. Hence
since that date there has been a requirement for vets to report any suspect SE
in dogs for further investigation. To date there has never been positive
identification of a TSE in a dog.
I hope this is helpful
Yours sincerely 4
HUGH MCDONAGH BSE CORRESPONDENCE SECTION
======================================
HOUND SURVEY
I am sorry, but I really could have been a co-signatory of Gerald's
minute.
I do NOT think that we can justify devoting any resources to this study,
especially as larger and more important projects such as the pathogenesis study
will be quite demanding.
If there is a POLITICAL need to continue with the examination of hound
brains then it should be passed entirely to the VI Service.
J W WILESMITH Epidemiology Unit 18 October 1991
Mr. R Bradley
cc: Mr. G A H Wells
3.3. Mr R J Higgins in conjunction with Mr G A Wells and Mr A C Scott would
by the end of the year, indentify the three brains that were from the
''POSITIVE'' end of the lesion spectrum.
TSE in dogs have not been documented simply because OF THE ONLY STUDY,
those brain tissue samples were screwed up too. see my investigation of this
here, and to follow, later follow up, a letter from defra, AND SEE SUSPICIOUS
BRAIN TISSUE SAF's. ...TSS
TSE & HOUNDS
GAH WELLS (very important statement here...TSS)
HOUND STUDY
AS implied in the Inset 25 we must not _ASSUME_ that transmission of BSE to
other species will invariably present pathology typical of a scrapie-like
disease.
snip...
76 pages on hound study;
snip...
The spongiform changes were not pathognomonic (ie. conclusive proof) for
prion disease, as they were atypical, being largely present in white matter
rather than grey matter in the brain and spinal cord. However, Tony Scott, then
head of electron microscopy work on TSEs, had no doubt that these SAFs were
genuine and that these hounds therefore must have had a scrapie-like disease. I
reviewed all the sections myself (original notes appended) and although the
pathology was not typical, I could not exclude the possibility that this was a
scrapie-like disorder, as white matter vacuolation is seen in TSEs and Wallerian
degeneration was also present in the white matter of the hounds, another feature
of scrapie.
38.I reviewed the literature on hound neuropathology, and discovered that
micrographs and descriptive neuropathology from papers on 'hound ataxia'
mirrored those in material from Robert Higgins' hound survey. Dr Tony Palmer
(Cambridge) had done much of this work, and I obtained original sections from
hound ataxia cases from him. This enabled me provisionally to conclude that
Robert Higgins had in all probability detected hound ataxia, but also that hound
ataxia itself was possibly a TSE. Gerald Wells confirmed in 'blind' examination
of single restricted microscopic fields that there was no distinction between
the white matter vacuolation present in BSE and scrapie cases, and that
occurring in hound ataxia and the hound survey cases.
39.Hound ataxia had reportedly been occurring since the 1930's, and a known
risk factor for its development was the feeding to hounds of downer cows, and
particularly bovine offal. Circumstantial evidence suggests that bovine offal
may also be causal in FSE, and TME in mink. Despite the inconclusive nature of
the neuropathology, it was clearly evident that this putative canine spongiform
encephalopathy merited further investigation.
40.The inconclusive results in hounds were never confirmed, nor was the
link with hound ataxia pursued. I telephoned Robert Higgins six years after he
first sent the slides to CVL. I was informed that despite his submitting a
yearly report to the CVO including the suggestion that the hound work be
continued, no further work had been done since 1991. This was surprising, to say
the very least.
41.The hound work could have provided valuable evidence that a scrapie-like
agent may have been present in cattle offal long before the BSE epidemic was
recognised. The MAFF hound survey remains unpublished.
Histopathological support to various other published MAFF experiments
42.These included neuropathological examination of material from
experiments studying the attempted transmission of BSE to chickens and pigs (CVL
1991) and to mice (RVC 1994).
It was thought likely that at least some, and probably all, of the cases in
zoo animals were caused by the BSE agent. Strong support for this hypothesis
came from the findings of Bruce and others (1994) ( Bruce, M.E., Chree, A.,
McConnell, I., Foster, J., Pearson, G. & Fraser, H. (1994) Transmission of
bovine spongiform encephalopathy and scrapie to mice: strain variation and
species barrier. Philosophical Transactions of the Royal Society B 343, 405-411:
J/PTRSL/343/405 ), who demonstrated that the pattern of variation in incubation
period and lesion profile in six strains of mice inoculated with brain
homogenates from an affected kudu and the nyala, was similar to that seen when
this panel of mouse strains was inoculated with brain from cattle with BSE. The
affected zoo bovids were all from herds that were exposed to feeds that were
likely to have contained contaminated ruminant-derived protein and the zoo
felids had been exposed, if only occasionally in some cases, to tissues from
cattle unfit for human consumption.
snip...
NEW URL ;
Friday, March 8, 2013
Dogs may have been used to make Petfood and animal feed
Tuesday, June 11, 2013
Weld County Bi-Products dba Fort Morgan Pet Foods 6/1/12 significant
deviations from requirements in FDA regulations that are intended to reduce the
risk of bovine spongiform encephalopathy (BSE) within the United States
Comment from Terry Singeltary This is a Comment on the Food and Drug
Administration (FDA) Notice: Draft Guidance for Industry on Ensuring Safety of
Animal Feed Maintained and Fed On-Farm; Availability
For related information, Open Docket Folder Docket folder icon
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Comment View document:
Guidance for Industry Ensuring Safety of Animal Feed Maintained and Fed
On-Farm Draft Guidance FDA-2014-D-1180 Singeltary Comment
Greetings FDA et al,
I wish to comment on Guidance for Industry Ensuring Safety of Animal Feed
Maintained and Fed On-Farm Draft Guidance FDA-2014-D-1180.
Once again, I wish to kindly bring up the failed attempt of the FDA and the
ruminant to ruminant mad cow feed ban of August 4, 1997. This feed ban is still
failing today, as we speak. Even more worrisome, is the fact it is still legal
to feed cervids to cervids in the USA, in fact, the FDA only _recommends_ that
deer and elk considered to be of _high_ risk for CWD do not enter the animal
food chain, but there is NO law, its only voluntary, a recipe for a TSE prion
disaster, as we have seen with the ruminant to ruminant feed ban for cattle,
where in 2007, one decade post August 1997 mad cow feed ban, where in 2007
10,000,000 POUNDS OF BANNED BLOOD LACED MEAT AND BONE MEAL WHEN OUT INTO
COMMERCE, TO BE FED OUT. Since 2007, these BSE feed ban rules have been breached
time and time again. tons and tons of mad cow feed went out in Alabama as well,
where one of the mad cows were documented, just the year before in 2006, and in
2013 and 2014, breaches so bad (OAI) Official Action Indicated were issued.
those are like the one issued where 10 million pounds of banned blood laced meat
and bone meal were fed out.
What is the use of having a Guidance for Industry Ensuring Safety of Animal
Feed Maintained and Fed On-Farm Draft Guidance FDA-2014-D-1180, if it cannot be
enforced, as we have seen with a mandatory ruminant to ruminant feed ban?
I strenuously once again urge the FDA and its industry constituents, to
make it MANDATORY that all ruminant feed be banned to all ruminants, and this
should include all cervids as soon as possible for the following
reasons...
======
In the USA, under the Food and Drug Administrations BSE Feed Regulation (21
CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from
deer and elk is prohibited for use in feed for ruminant animals. With regards to
feed for non-ruminant animals, under FDA law, CWD positive deer may not be used
for any animal feed or feed ingredients. For elk and deer considered at high
risk for CWD, the FDA recommends that these animals do not enter the animal feed
system.
***However, this recommendation is guidance and not a requirement by law.
======
31 Jan 2015 at 20:14 GMT
*** Ruminant feed ban for cervids in the United States? ***
31 Jan 2015 at 20:14 GMT
19 May 2010 at 21:21 GMT
*** Singeltary reply ; Molecular, Biochemical and Genetic Characteristics
of BSE in Canada Singeltary reply ;
Tuesday, December 23, 2014
FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED
VIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE DECEMBER 2014 BSE TSE PRION
2013
Sunday, December 15, 2013
FDA PART 589 -- SUBSTANCES PROHIBITED FROM USE IN ANIMAL FOOD OR FEED
VIOLATIONS OFFICIAL ACTION INDICATED OAI UPDATE DECEMBER 2013 UPDATE
DOCKET-- 03D-0186 -- FDA Issues Draft Guidance on Use of Material From Deer
and Elk in Animal Feed; Availability Date: Fri, 16 May 2003 11:47:37 0500 EMC 1
Terry S. Singeltary Sr. Vol #: 1
PLEASE SEE FULL TEXT SUBMISSION ;
10,000,000+ LBS. of PROHIBITED BANNED MAD COW FEED I.E. BLOOD LACED MBM IN
COMMERCE USA 2007
Date: March 21, 2007 at 2:27 pm PST
REASON
Blood meal used to make cattle feed was recalled because it was cross-
contaminated with prohibited bovine meat and bone meal that had been
manufactured on common equipment and labeling did not bear cautionary BSE
statement.
VOLUME OF PRODUCT IN COMMERCE
42,090 lbs.
DISTRIBUTION
WI
REASON
Products manufactured from bulk feed containing blood meal that was cross
contaminated with prohibited meat and bone meal and the labeling did not bear
cautionary BSE statement.
VOLUME OF PRODUCT IN COMMERCE
9,997,976 lbs.
DISTRIBUTION
ID and NV
END OF ENFORCEMENT REPORT FOR MARCH 21, 2007
Terry S. Singeltary Sr.
*** See attached file(s) No documents available. Attachments View All (1)
Guidance for Industry Ensuring Safety of Animal Feed Maintained and Fed On-Farm
Terry Singeltary Comment View Attachment:
Sunday, April 5, 2015
*** Guidance for Industry Ensuring Safety of Animal Feed Maintained and Fed
On-Farm Draft Guidance FDA-2014-D-1180 ***
Sunday, April 12, 2015
*** Research Project: Transmission, Differentiation, and Pathobiology of
Transmissible Spongiform Encephalopathies 2014 Annual Report ***
http://transmissiblespongiformencephalopathy.blogspot.com/2015/04/research-project-transmission.html
Wednesday, April 15, 2015
KURU Transmissible Spongiform Encephalopthy TSE Prion Disease VIDEO
Self-Propagative Replication of Ab Oligomers Suggests Potential
Transmissibility in Alzheimer Disease
Received July 24, 2014; Accepted September 16, 2014; Published November 3,
2014
Singeltary comment ;
Saturday, December 13, 2014
Terry S. Singeltary Sr. Publications TSE prion disease
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14,
2001 JAMA
snip...
TSS
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