Tuesday, February 11, 2020

Predators, Scavengers, and trans locating the CWD TSE Prion

Predators, Scavengers, and trans locating the CWD TSE Prion

TO use wolves as a tool as a predator to try and stop CWD TSE Prion would be foolish imo...see;

study indicate that coyotes can pass infectious prions via their feces for at least 3 days post ingestion, demonstrating that mammalian scavengers could contribute to the translocation and contamination of CWD in the environment. 


Biol. Rev. (2019), pp. 000–000. 1 doi: 10.1111/brv.12568 

The ecology of chronic wasting disease in wildlife 

Luis E. Escobar1,∗,† , Sandra Pritzkow2,†, Steven N. Winter1 , Daniel A. Grear3, Megan S. Kirchgessner4, Ernesto Dominguez-Villegas5, Gustavo Machado6 , A. Townsend Peterson7,† and Claudio Soto2,†

snip...

Beyond the landscape, other species in the community can influence CWD transmission. Empirical evidence supports the role of predators in the removal of sick and infectious prey across diverse disease systems (Packer et al., 2003). For example, grey wolf (Canis lupus) presence reduced seroprevalence of bovine-virus-diarrhea in elk (Barber-Meyer & White, 2005), and mountain lions (Puma concolor) selectively predate on CWD-infected mule deer (Krumm et al., 2010). Other native large predators, such as grey wolves and bears (Ursus spp.), may similarly influence the prevalence and geographic distribution of CWD in wild reservoirs, as demonstrated through modelling applications (Hobbs, 2006; Wild et al., 2011). Additionally, numbers and geographic range of predators, including wolves and black bears (Ursus americanus), can be successfully managed and controlled via wildlife management methods (Meagher & Phillips, 1980; Clark, Huber & Servheen, 2002; Soorae, 2013).

Research assessing the role of predators in CWD transmission requires a multidisciplinary approach integrating expertise in human dimension, epidemiology, and ecology. Alternatively, carnivores and scavengers could potentially facilitate CWD spread to distant areas by translocating infectious prions from prey. This has been suggested for scats of coyotes (Canis latrans), raccoons (Procyon lotor) (Hamir et al., 2007; Moore et al., 2019), and crows (Corvus spp.) (Fischer et al., 2013), but has not been tested empirically. Scats may also be of potential utility in CWD surveillance and early detection, as predators can selectively predate CWD-infected cervids (Nichols et al., 2015). Whether predators can significantly improve the control and surveillance of CWD is unknown but deserves deeper exploration. Predator or scavenger scats have not been used in CWD surveillance to date.

snip...


Update on chronic wasting disease (CWD) III

EFSA Panel on Biological Hazards (BIOHAZ) 

Kostas Koutsoumanis Ana Allende Avelino Alvarez‐Ordoňez Declan Bolton Sara Bover‐Cid Marianne Chemaly Robert Davies Alessandra De Cesare Lieve Herman Friederike Hilbert Roland Lindqvist Maarten Nauta Luisa Peixe Giuseppe Ru Panagiotis Skandamis Elisabetta Suffredini Olivier Andreoletti Sylvie L Benestad Emmanuel Comoy Romolo Nonno Teresa da Silva Felicio Angel Ortiz‐Pelaez Marion M Simmons … See fewer authors First published:11 November 2019 https://doi.org/10.2903/j.efsa.2019.5863

Correspondence: biohaz@efsa.europa.eu

Requestor: European Commission

Question number: EFSA‐Q‐2018‐00763

Panel members: Kostas Koutsoumanis, Ana Allende, Avelino Alvarez‐Ordoñez, Declan Bolton, Sara Bover‐Cid, Marianne Chemaly, Robert Davies, Alessandra De Cesare, Lieve Herman, Friederike Hilbert, Roland Lindqvist, Maarten Nauta, Luisa Peixe, Giuseppe Ru, Marion M. Simmons, Panagiotis Skandamis and Elisabetta Suffredini.

Acknowledgements: The EFSA Panel on Biological Hazards (BIOHAZ) wishes to acknowledge all European and North American researchers who provided data and information for this scientific output, and Maria Francesca Iulietto for her contributions to the draft.

Adopted: 26 September 2019

This article was originally published on the EFSA website www.efsa.europa.eu on 7 November 2019

SNIP...

Using data from the NA CWD experience, 13 groups of risk factors have been identified based on their biological plausibility to spread CWD. Some of these are supported by epidemiological evidence from NA CWD studies with variable strength of evidence after applying the score‐based ranking, while others remain hypothetical:

Natural movement of live wild deer from infected areas,

Man‐mediated movement of live farmed/free‐ranging deer from infected areas,

Failure to separate live farmed and free‐ranging deer,

High deer density,

Species‐specific social organisation,

Sex‐related behaviours,

Natural or man‐mediated animal aggregation,

Consumption of forage grown on contaminated soil,

Fallen stock or inappropriate disposal of carcasses and slaughter by‐products,

***> Movement of other animals (working dogs, scavengers, predators),

Transfer of inanimate vehicles of contamination (fomites),

Environmental persistence of prions,

Host genetics.

SNIP...

Whether the natural host range of CWD in North America extends beyond the family Cervidae is currently unclear and no natural infections have been reported so far in wildlife species with substantial overlapping geographical range and which could play a role in the spread of CWD, such as predators and scavengers.

3.2.1.2 Non‐cervid domestic species

The remarkably high rate of natural CWD transmission in the ongoing NA epidemics raises the question of the risk to livestock grazing on CWD‐contaminated shared rangeland and subsequently developing a novel CWD‐related prion disease. This issue has been investigated by transmitting CWD via experimental challenge to cattle, sheep and pigs and to tg mouse lines expressing the relevant species PrP.

For cattle challenged with CWD, PrPSc was detected in approximately 40% of intracerebrally inoculated animals (Hamir et al., 2005, 2006a, 2007). Tg mice expressing bovine PrP have also been challenged with CWD and while published studies have negative outcomes (Tamguney et al., 2009b), unpublished data provided for the purposes of this Opinion indicate that some transmission of individual isolates to bovinised mice is possible (Table 1).

In small ruminant recipients, a low rate of transmission was reported between 35 and 72 months post‐infection (mpi) in ARQ/ARQ and ARQ/VRQ sheep intracerebrally challenged with mule deer CWD (Hamir et al., 2006b), while two out of two ARQ/ARQ sheep intracerebrally inoculated with elk CWD developed clinical disease after 28 mpi (Madsen‐Bouterse et al., 2016). However, tg mice expressing ARQ sheep PrP were resistant (Tamguney et al., 2006) and tg mice expressing the VRQ PrP allele were poorly susceptible to clinical disease (Beringue et al., 2012; Madsen‐Bouterse et al., 2016). In contrast, tg mice expressing VRQ sheep PrP challenged with CWD have resulted in highly efficient, life‐long asymptomatic replication of these prions in the spleen tissue (Beringue et al., 2012).

A recent study investigated the potential for swine to serve as hosts of the CWD agent(s) by intracerebral or oral challenge of crossbred piglets (Moore et al., 2016b, 2017). Pigs sacrificed at 6 mpi, approximately the age at which pigs reach market weight, were clinically healthy and negative by diagnostic tests, although low‐level CWD agent replication could be detected in the CNS by bioassay in tg cervinised mice. Among pigs that were incubated for up to 73 mpi, some gave diagnostic evidence of CWD replication in the brain between 42 and 72 mpi. Importantly, this was observed also in one orally challenged pig at 64 mpi and the presence of low‐level CWD replication was confirmed by mouse bioassay. The authors of this study argued that pigs can support low‐level amplification of CWD prions, although the species barrier to CWD infection is relatively high and that the detection of infectivity in orally inoculated pigs with a mouse bioassay raises the possibility that naturally exposed pigs could act as a reservoir of CWD infectivity.

3.2.1.3 Other species

Studies have demonstrated that the CWD agent(s) can be transmitted by the IC route in several species of rodents, such as voles (Subfamily Arvicolinae), deer mice (Peromyscus maniculatus), mice and hamsters (Subfamily Cricetinae). The susceptibility was, however, variable, being high in voles and deer mice but lower in mice and hamsters (Raymond et al., 2007; Heisey et al., 2010; Kurt et al., 2011; Di et al., 2013; Lee et al., 2013). Mink (subfamily Mustelinae) (Harrington et al., 2008), ferrets (Mustela putorius) (Bartz et al., 1998; Sigurdson et al., 2008) and cats (Mathiason et al., 2013) were susceptible to IC challenge with NA CWD sources, while CWD transmitted poorly to raccoons (Procyon lotor) by the IC route (Moore et al., 2019).

SNIP...

10. Movement of other animals (working dogs, scavengers, predators) 

I & II Working dogs are moved for hunting or sledging competitions 

Defra (2016a,b) review F Y Faeces of dogs accompanying hunters returning from infected areas/countries can serve as a vehicle for prions contributing to the spread of the infectious agent in the environment (Defra, 2016a,b)

Scavengers Various species of (raptors, corvids) birds or mammals that feed on animal carcasses can act as spreaders of the infection. It has been shown that carcasses abandoned in the field in an area of Wisconsin were a source of food for at least 14 species of mammals and 14 species of birds. Carcasses could persist in the field from 18 to 101 days depending on the season and year. The involvement of the birds also suggests that the infectious agent could be transferred at great distances from the infected carcass (Jennelle et al., 2009) Jennelle et al. (2009) other F N

Predators. Prion‐infected deer were much more likely to be killed by mountain lions than uninfected deer (Miller et al., 2008). The presence of prions and their infectious ability in cervinised transgenic mice have been demonstrated in the faeces of coyotes (Canis latrans) 3 days after they had fed on with infected deer carcasses (Nichols et al., 2015). Faeces of predators (in North America e.g. coyotes or pumas) can serve as a vehicle for prions contributing to the spread of the infectious agent in the environment. Miller et al. (2008) cohort B N Nichols et al. (2015) other

11. Transfer of inanimate vehicles of contamination (fomites) 

I & II Hunting clothing, boots or knives poorly cleaned and used in infected and areas, could help disseminate contaminated material (e.g. clods of soil attached to their boots) (Defra, 2016a,b) Defra (2016a,b) review F Y

During their activity, hunters have more opportunities than any other segment of the population for direct exposure to infected material (secretions, excreta, infected tissues) (Saunders et al., 2012). Saunders et al. (2012) review F

Wood, rocks, plastic, glass, cement, stainless steel and aluminium can all bind, retain and release prions and therefore act efficiently as fomites and transmit disease. Not every strain had the same affinities. Effective transmission only required contact with the contaminated surfaces – nothing more invasive. Good binding to wood and rock have implications for environmental contamination in natural/wildlife settings (Pritzkow et al., 2018) Pritzkow et al. (2018)

12. Environmental persistence of prions I & II Prions, due to their resistance to degradation, can persist for years by binding to soil particles without losing their infectious potential. For instance, it has been shown that BSE infectivity survives burial for 5 years with only limited spread (Williams and Young, 1992; Miller and Williams, 2003; Miller et al., 2004; Johnson et al., 2007; Saunders et al., 2012; Somerville et al., 2019) Williams and Young (1992) review F N

Miller and Williams (2003) cohort B

Miller et al. (2004) int A

Johnson et al. (2007) other F

Saunders et al. (2012) review F

Somerville et al. (2019) other F

Such a persistence allows an infected animal to cause secondary infections long after its death (Almberg et al., 2011). Almberg et al. (2011) simul E

SNIP...

4.3 Answer to ToR3

To identify risk factors that can facilitate the spread of CWD in the European Union given the current situation of the disease.

Using data from the NA CWD experience, 13 groups of risk factors have been identified based on their biological plausibility to spread CWD. Some of these are supported by epidemiological evidence from NA CWD studies with variable strength of evidence, while others remain hypothetical:

1. Natural movement of live wild deer from infected areas.

2. Man‐mediated movement of live farmed/free‐ranging deer from infected areas.

3. Failure to separate live farmed and free‐ranging deer.

4. High deer density.

5. Species‐specific social organisation.

6. Sex‐related behaviours.

7. Natural or man‐mediated animal aggregation.

8. Consumption of forage grown on contaminated soil.

9. Fallen stock or inappropriate disposal of carcasses and slaughter by‐products. 

10. Movement of other animals (working dogs, scavengers, predators). 

11. Transfer of inanimate vehicles of contamination (fomites).

12. Environmental persistence of prions.

13. Host genetics.

All the identified risk factors may contribute to the spread of the disease when it is associated with the accumulation of infectivity in peripheral tissues, a host phenotype that is compatible with a contagious disease.

A subset of risk factors (1,2,6,8,9,10,11,12 and 13) are relevant to cases of disease that do not involve peripheral accumulation of infectivity and are therefore less contagious or non‐contagious and may contribute to the spread of the disease mainly via environmental contamination following death. Some risk factors are man‐mediated and are considered preventable. Their management could contribute to a decrease in the theoretical risk of spread of CWD.

The potential co‐localisation of cervid species and disease phenotypes mean that all the identified groups of risk factors should be taken into account when considering interventions.

SNIP...SEE FULL TEXT;


TUESDAY, FEBRUARY 04, 2020 

Predicting the spread-risk potential of chronic wasting disease to sympatric ungulate species



THURSDAY, DECEMBER 19, 2019

TSE surveillance statistics exotic species and domestic cats Update December 2019

https://transmissiblespongiformencephalopathy.blogspot.com/2019/12/tse-surveillance-statistics-exotic.html

JOURNAL OF VIROLOGY, Jan. 2010, p. 210–215 Vol. 84, No. 1 0022-538X/10/$12.00 doi:10.1128/JVI.00560-09

Copyright © 2010, American Society for Microbiology. All Rights Reserved. 

Chronic Wasting Disease (CWD) Susceptibility of Several North American Rodents That Are Sympatric with Cervid CWD Epidemics

Dennis M. Heisey,1 * Natalie A. Mickelsen,1 Jay R. Schneider,1 Christopher J. Johnson,1,2 Chad J. Johnson,1,3 Julia A. Langenberg,4 Philip N. Bochsler,5 Delwyn P. Keane,5 and Daniel J. Barr5

Prion Research Laboratory, USGS National Wildlife Health Center, Madison, Wisconsin1 ; Montana Cooperative Fishery Research Unit, Montana State University, Bozeman, Montana2 ; University of Wisconsin School of Veterinary Medicine, Department of Comparative Biosciences, Madison, Wisconsin3 ; Wisconsin Department of Natural Resources, Madison, Wisconsin4 ; and Wisconsin Veterinary Diagnostic Lab, Madison, Wisconsin5 Received 18 March 2009/Accepted 6 October 2009

Chronic wasting disease (CWD) is a highly contagious always fatal neurodegenerative disease that is currently known to naturally infect only species of the deer family, Cervidae. CWD epidemics are occurring in free-ranging cervids at several locations in North America, and other wildlife species are certainly being exposed to infectious material. To assess the potential for transmission, we intracerebrally inoculated four species of epidemic-sympatric rodents with CWD. Transmission was efficient in all species; the onset of disease was faster in the two vole species than the two Peromyscus spp. The results for inocula prepared from CWD-positive deer with or without CWD-resistant genotypes were similar. Survival times were substantially shortened upon second passage, demonstrating adaptation. Unlike all other known prion protein sequences for cricetid rodents that possess asparagine at position 170, our red-backed voles expressed serine and refute previous suggestions that a serine in this position substantially reduces susceptibility to CWD. Given the scavenging habits of these rodent species, the apparent persistence of CWD prions in the environment, and the inevitable exposure of these rodents to CWD prions, our intracerebral challenge results indicate that further investigation of the possibility of natural transmission is warranted.

snip...


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 ; 

http://www.cwd-info.org/pdf/3rd_CWD_Symposium_utah.pdf 


Evidence indicates that CWD prions can be consumed and moved by predators and scavengers feeding on infected carcasses, with the prion remaining infectious after it passes through that animal (Fischer et al., 2013)(Nichols et al., 2015). 


Friday, August 8, 2008

PS 76-59: White-tailed deer carcass decomposition and risk of chronic wasting disease exposure to scavenger communities in Wisconsin

Chris S. Jennelle, Michael D. Samuel, Cherrie A. Nolden, and Elizabeth A. Berkley. University of Wisconsin

snip...

Chronic wasting disease (CWD) is an infectious transmissible spongiform encephalopathy (TSE) afflicting members of the family Cervidae, and causes neurodegeneration and ultimately death. While there have been no reports of natural cross-species transmission of CWD outside this group, we addressed the role of white-tailed deer (Odocoileus virginianus) carcasses as environmental sources of CWD in Wisconsin. Our objectives were to estimate rates of deer carcass and gut pile decomposition in the environment, characterize vertebrate scavenger communities, and quantify the relative activity of scavengers to determine CWD exposure risk. We placed 40 disease-free deer carcasses and nine gut piles in the CWD-affected area of Wisconsin from September to April in 2003 through 2005. We used photos from remotely operated cameras to characterize scavenger communities and relative activity. We used Kaplan-Meier survival analysis and a generalized linear mixed model to quantify the driving factors and rate of carcass removal (decomposition) from the environment.

Results/Conclusions

We recorded 14 species of scavenging mammals (six visiting species), and eight species of scavenging birds (14 visiting species). Prominent scavengers included American crows (Corvus brachyrhynchos), raccoons (Procyon lotor), and Virginia opossums (Didelphis virginiana). We found no evidence that deer directly consumed conspecific remains, although they visited them frequently. Domestic dogs (Canis familiaris), cats (Felis catus), and cows (Bos spp.) either scavenged or visited carcass sites, which could increase exposure risk of CWD to humans and human food supplies. Deer carcasses persisted for a median of 18 to 101 days, while gut piles lasted for a median of three days. Habitat did not influence carcass decomposition, but mammalian and avian scavenger activity and higher temperatures (proxy for microbial and arthropod activity) were associated with greater rates of carcass removal. Infected deer carcasses serve as environmental sources of CWD prions to a wide variety of mammalian and avian scavengers. Such sources of infectious material likely influence the maintenance and spread of CWD (in particular), and should be considered in the dynamics of other disease systems as well. Prudence would dictate the use of preemptive management strategies, and we highlight strategies for carcass disposal to mitigate the influence of carcasses as environmental sources of infectious diseases.

See more of PS 76 - Latebreaking: Disease and Epidemiology See more of Latebreakers

See more of The 93rd ESA Annual Meeting (August 3 -- August 8, 2008)



THURSDAY, MARCH 08, 2018

Cervid, Wild Hogs, Coyotes, Wolves, Cats, Rodents, Gut Piles and Scavengers, A Potential Risk as Regards Disease Transmission CWD TSE Prio


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


CWD TSE PRION AND GUT PILES


Monday, July 13, 2009 

Deer Carcass Decomposition and Potential Scavenger Exposure to Chronic Wasting Disease 


This provided support for the adaptation and transmission of orally consumed prions, as well as evidence that felids are susceptible to prion infection. Chronic wasting disease has been shown to be readily transmitted via multiple means, including direct contact with a CWD-infected cervid (6–8), exposure to infectious CWD prions in the environment (9, 10), and ingestion of bodily fluids and tissues from a CWD-infected cervid (11–15). 

Recent research by Miller and colleagues (16) performed in an area of Colorado where CWD is endemic, where nearly one-fourth of the adult mule deer are prion infected, confirmed the assumption that afflicted animals become prey to mountain lions more often than healthy ones. 

In addition, experimental studies have demonstrated that prions infect and cause disease in several rodent scavenger species (i.e., voles and deer mice) overlapping in distribution with CWD and scrapie outbreaks (17, 18). 

Such scavenging rodents are known to cannibalize and are also an important food source for many larger predators and scavengers in nature, hence providing a reservoir and a potential bridge for cross-species transmission of prions from the natural host to predator/scavenger species. 

Thus, the facile transmission of CWD, coupled with its growing geographical distribution (19) and propensity to persist in the environment (20–22), provide ample opportunity for the bioavailability of CWD prions to many species coexisting with CWD in nature, including felids.


Thursday, December 25, 2008

Lions and Prions and Deer Demise

snip...

Greetings,

A disturbing study indeed, but even more disturbing, the fact that this very study shows the potential for transmission of the TSE agent into the wild of yet another species in the USA. Science has shown that the feline is most susceptible to the TSE agent. Will CWD be the demise of the mountain lions, cougars and such in the USA? How many have ever been tested in the USA? I recall there is a study taking place ; Review A prion disease of cervids: Chronic wasting disease Christina J. Sigurdson et al ;

Mountain lion (Puma concolor) susceptibility to experimental feeding of CWD prions is currently under investigation (M. Miller and L. Wolfe, personal communication).

WHAT about multiple strains of CWD ?

0C7.04

North American Cervids Harbor Two Distinct CWD Strains

snip...


SNIP...SEE ;



Now, we know that cwd and scrapie tse prion will transmit by oral routes to pigs, and a apparently large outbreak of a TSE Prion disease in a new livestock species in Africa, the camel.

Never say never, re canine and tse prion, bad idea, just my opinion...


16 to 21 years is a long time after exposure for environmental contamination of the tse prion...

CWD prions remain infectious after passage through the digestive system of coyotes (Canis latrans) 

Tracy A Nichols1,*, Justin W Fischer1 , Terry R Spraker2,3, Qingzhong Kong4 , and Kurt C VerCauteren1 1 National Wildlife Research Center; United States Department of Agriculture; Animal and Plant Health Inspection Service; Wildlife Services; Fort Collins, CO USA; 2 Colorado State University Diagnostic Laboratory; College of Veterinary Medicine; Colorado State University; Fort Collins, CO USA; 3 Department of Microbiology, Immunology and Pathology; College of Veterinary Medicine and Biomedical Sciences; Colorado State University Prion Research Center; Fort Collins, CO USA; 4 National Prion Disease Pathology Surveillance Center; Institute of Pathology; Case Western Reserve University; Cleveland, OH USA

ABSTRACT. Chronic wasting disease (CWD) is a geographically expanding prion disease of wild and captive cervids in North America. Disease can be transmitted directly, animal to animal, or indirectly via the environment. CWD contamination can occur residually in the environment via soil, water, and forage following deposition of bodily fluids such as urine, saliva, and feces, or by the decomposition of carcasses. Recent work has indicated that plants may even take up prions into the stems and leaves. When a carcass or gut pile is present in the environment, a large number of avian and mammalian species visit and consume the carrion. Additionally, predators like coyotes, likely select for disease-compromised cervids. Natural cross-species CWD transmission has not been documented, however, passage of infectious prion material has been observed in the feces of crows. In this study we evaluated the ability of CWD-infected brain material to pass through the gastrointestinal tract of coyotes (Canis latrans) following oral ingestion, and be infectious in a cervidized transgenic mouse model. Results from this study indicate that coyotes can pass infectious prions via their feces for at least 3 days post ingestion, demonstrating that mammalian scavengers could contribute to the translocation and contamination of CWD in the environment.


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, identify the three brains that were from the ''POSITIVE'' end of the lesion spectrum.


HOUND SURVEY PATHOLOGICAL REPORT (see positive results) and MAD DOGS AND ENGLISHMAN...

ya'll thought i was making this stuff up didn't ya...i don't make this stuff up!


EP-021 Canine Prions: A New Form of Prion Disease
Mourad Tayebi1, Monique A David2, Brian Summers3
1 University of Melbourne, Veterinary Sciences, Australia; 2Ausbiologics, Sydney, Australia; 3Royal Veterinary College, London, UK
The origin of bovine spongiform encephalopathy (BSE), which rapidly evolved into a major epidemic remains unresolved and was initially widely attributed to transmission of sheep scrapie to cattle with contaminated feed prepared from rendered sheep carcasses. Alternative transmission hypotheses also include feed contaminated with unrecognized subclinical case(s) of bovine prion disease or with prion-infected human remains. However, following the demonstration of a BSE case exhibiting the novel mutation E211 K, similar to the E200K mutation associated with most genetic CJD in humans, support for a genetic origin of prion disease in cattle is gaining momentum. In contrast to other animal species such as feline, the canine species seems to be resistant to prion disease as no canine prion cases were previously reported.
We describe here three cases of Rottweiler puppy (called RWD cases) with neurological deficits and spongiform change. We used animal bioassays and in vitro studies to show efficient interspecies transmission of this novel canidae prion isolate to other species.
Biochemical studies revealed the presence of partially proteinase K (PK)-resistant fragment and immunohistochemistry displayed staining for PrPSc in the cerebral cortex. Importantly, interspecies transmission of canine PrPSc derived from RWD3 brain homogenates following inoculation of hamsters led to signs of prion disease and replication of PrPSc in brains, spinal cords and spleens of these animals.
These findings if confirmed by further cases of prion disease in canidae and regardless of the origin of the disease would have a major impact on animal and public health.
PRION 2016 TOKYO
EP-021 Canine Prions: A New Form of Prion Disease
Mourad Tayebi1, Monique A David2, Brian Summers3
1 University of Melbourne, Veterinary Sciences, Australia; 2Ausbiologics, Sydney, Australia; 3Royal Veterinary College, London, UK
The origin of bovine spongiform encephalopathy (BSE), which rapidly evolved into a major epidemic remains unresolved and was initially widely attributed to transmission of sheep scrapie to cattle with contaminated feed prepared from rendered sheep carcasses. Alternative transmission hypotheses also include feed contaminated with unrecognized subclinical case(s) of bovine prion disease or with prion-infected human remains. However, following the demonstration of a BSE case exhibiting the novel mutation E211 K, similar to the E200K mutation associated with most genetic CJD in humans, support for a genetic origin of prion disease in cattle is gaining momentum. In contrast to other animal species such as feline, the canine species seems to be resistant to prion disease as no canine prion cases were previously reported.
We describe here three cases of Rottweiler puppy (called RWD cases) with neurological deficits and spongiform change. We used animal bioassays and in vitro studies to show efficient interspecies transmission of this novel canidae prion isolate to other species.
Biochemical studies revealed the presence of partially proteinase K (PK)-resistant fragment and immunohistochemistry displayed staining for PrPSc in the cerebral cortex. Importantly, interspecies transmission of canine PrPSc derived from RWD3 brain homogenates following inoculation of hamsters led to signs of prion disease and replication of PrPSc in brains, spinal cords and spleens of these animals.
These findings if confirmed by further cases of prion disease in canidae and regardless of the origin of the disease would have a major impact on animal and public health.
PRION 2016 TOKYO
*** DEFRA TO SINGELTARY ON HOUND STUDY AND BSE 2001 ***
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  Bacliff Texas USA 77518
21 November 2001
Dear Mr Singeltary
TSE IN HOUNDS

Monday, March 26, 2012
CANINE SPONGIFORM ENCEPHALOPATHY: A NEW FORM OF ANIMAL PRION DISEASE
*** DEFRA TO SINGELTARY ON HOUND STUDY AND BSE 2001 ***
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

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

Monday, March 26, 2012
CANINE SPONGIFORM ENCEPHALOPATHY: A NEW FORM OF ANIMAL PRION DISEASE

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...

MONDAY, FEBRUARY 25, 2019

***> MAD DOGS AND ENGLISHMEN BSE, SCRAPIE, CWD, CJD, TSE PRION A REVIEW 2019



CDC

New Outbreak of TSE Prion in NEW LIVESTOCK SPECIES

Mad Camel Disease

Volume 24, Number 6—June 2018 Research 

Prion Disease in Dromedary Camels, Algeria Abstract

Prions cause fatal and transmissible neurodegenerative diseases, including Creutzfeldt-Jakob disease in humans, scrapie in small ruminants, and bovine spongiform encephalopathy (BSE). After the BSE epidemic, and the associated human infections, began in 1996 in the United Kingdom, general concerns have been raised about animal prions. We detected a prion disease in dromedary camels (Camelus dromedarius) in Algeria. Symptoms suggesting prion disease occurred in 3.1% of dromedaries brought for slaughter to the Ouargla abattoir in 2015–2016. We confirmed diagnosis by detecting pathognomonic neurodegeneration and disease-specific prion protein (PrPSc) in brain tissues from 3 symptomatic animals. Prion detection in lymphoid tissues is suggestive of the infectious nature of the disease. PrPSc biochemical characterization showed differences with BSE and scrapie. Our identification of this prion disease in a geographically widespread livestock species requires urgent enforcement of surveillance and assessment of the potential risks to human and animal health.

SNIP...

The possibility that dromedaries acquired the disease from eating prion-contaminated waste needs to be considered.

Tracing the origin of prion diseases is challenging. In the case of CPD, the traditional extensive and nomadic herding practices of dromedaries represent a formidable factor for accelerating the spread of the disease at long distances, making the path of its diffusion difficult to determine. Finally, the major import flows of live animals to Algeria from Niger, Mali, and Mauritania (27) should be investigated to trace the possible origin of CPD from other countries. Camels are a vital animal species for millions of persons globally. The world camel population has a yearly growth rate of 2.1% (28). In 2014, the population was estimated at ≈28 million animals, but this number is probably underestimated.. Approximately 88% of camels are found in Africa, especially eastern Africa, and 12% are found in Asia. Official data reported 350,000 dromedaries in Algeria in 2014 (28).

On the basis of phenotypic traits and sociogeographic criteria, several dromedary populations have been suggested to exist in Algeria (29). However, recent genetic studies in Algeria and Egypt point to a weak differentiation of the dromedary population as a consequence of historical use as a cross-continental beast of burden along trans-Saharan caravan routes, coupled with traditional extensive/nomadic herding practices (30).

Such genetic homogeneity also might be reflected in PRNP. Studies on PRNP variability in camels are therefore warranted to explore the existence of genotypes resistant to CPD, which could represent an important tool for CPD management as it was for breeding programs for scrapie eradication in sheep. In the past 10 years, the camel farming system has changed rapidly, with increasing setup of periurban dairy farms and dairy plants and diversification of camel products and market penetration (13). This evolution requires improved health standards for infectious diseases and, in light of CPD, for prion diseases.

The emergence of another prion disease in an animal species of crucial importance for millions of persons worldwide makes it necessary to assess the risk for humans and develop evidence-based policies to control and limit the spread of the disease in animals and minimize human exposure. The implementation of a surveillance system for prion diseases would be a first step to enable disease control and minimize human and animal exposure. Finally, the diagnostic capacity of prion diseases needs to be improved in all countries in Africa where dromedaries are part of the domestic livestock. https://wwwnc.cdc.gov/eid/article/24/6/17-2007_article ;

***> IMPORTS AND EXPORTS <***

***SEE MASSIVE AMOUNTS OF BANNED ANIMAL PROTEIN AKA MAD COW FEED IN COMMERCE USA DECADES AFTER POST BAN ***



Friday, December 14, 2012

DEFRA U.K. What is the risk of Chronic Wasting Disease CWD being introduced into Great Britain? A Qualitative Risk Assessment October 2012

snip.....

In the USA, under the Food and Drug Administration's 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.

Animals considered at high risk for CWD include:

1) animals from areas declared to be endemic for CWD and/or to be CWD eradication zones and

2) deer and elk that at some time during the 60-month period prior to slaughter were in a captive herd that contained a CWD-positive animal.

Therefore, in the USA, materials from cervids other than CWD positive animals may be used in animal feed and feed ingredients for non-ruminants.

The amount of animal PAP that is of deer and/or elk origin imported from the USA to GB can not be determined, however, as it is not specified in TRACES. It may constitute a small percentage of the 8412 kilos of non-fish origin processed animal proteins that were imported from US into GB in 2011.

Overall, therefore, it is considered there is a __greater than negligible risk___ that (nonruminant) animal feed and pet food containing deer and/or elk protein is imported into GB.

There is uncertainty associated with this estimate given the lack of data on the amount of deer and/or elk protein possibly being imported in these products.

snip.....

36% in 2007 (Almberg et al., 2011). In such areas, population declines of deer of up to 30 to 50% have been observed (Almberg et al., 2011). In areas of Colorado, the prevalence can be as high as 30% (EFSA, 2011).

The clinical signs of CWD in affected adults are weight loss and behavioural changes that can span weeks or months (Williams, 2005). In addition, signs might include excessive salivation, behavioural alterations including a fixed stare and changes in interaction with other animals in the herd, and an altered stance (Williams, 2005). These signs are indistinguishable from cervids experimentally infected with bovine spongiform encephalopathy (BSE).

Given this, if CWD was to be introduced into countries with BSE such as GB, for example, infected deer populations would need to be tested to differentiate if they were infected with CWD or BSE to minimise the risk of BSE entering the human food-chain via affected venison.

snip.....

The rate of transmission of CWD has been reported to be as high as 30% and can approach 100% among captive animals in endemic areas (Safar et al., 2008).

snip.....

In summary, in endemic areas, there is a medium probability that the soil and surrounding environment is contaminated with CWD prions and in a bioavailable form. In rural areas where CWD has not been reported and deer are present, there is a greater than negligible risk the soil is contaminated with CWD prion.

snip.....

In summary, given the volume of tourists, hunters and servicemen moving between GB and North America, the probability of at least one person travelling to/from a CWD affected area and, in doing so, contaminating their clothing, footwear and/or equipment prior to arriving in GB is greater than negligible... For deer hunters, specifically, the risk is likely to be greater given the increased contact with deer and their environment. However, there is significant uncertainty associated with these estimates.

snip.....

Therefore, it is considered that farmed and park deer may have a higher probability of exposure to CWD transferred to the environment than wild deer given the restricted habitat range and higher frequency of contact with tourists and returning GB residents.

snip.....



***> In summary, our results establish aerosols as a surprisingly efficient modality of prion transmission. This novel pathway of prion transmission is not only conceptually relevant for the field of prion research, but also highlights a hitherto unappreciated risk factor for laboratory personnel and personnel of the meat processing industry. In the light of these findings, it may be appropriate to revise current prion-related biosafety guidelines and health standards in diagnostic and scientific laboratories being potentially confronted with prion infected materials. While we did not investigate whether production of prion aerosols in nature suffices to cause horizontal prion transmission, the finding of prions in biological fluids such as saliva, urine and blood suggests that it may be worth testing this possibility in future studies.



Adriano Aguzzi ''We even showed that a prion AEROSOL will infect 100% of mice within 10 seconds of exposure''

WOW!...tss

THURSDAY, AUGUST 08, 2019 

Raccoons accumulate PrPSc after intracranial inoculation with the agents of chronic wasting disease (CWD) or transmissible mink encephalopathy (TME) but not atypical scrapie


Rabbits are not resistant to prion infection

Francesca Chianinia,1, Natalia Fernández-Borgesb,c,1, Enric Vidald , Louise Gibbarda , Belén Pintadoe , Jorge de Castroc , Suzette A. Priolaf , Scott Hamiltona , Samantha L. Eatona , Jeanie Finlaysona , Yvonne Panga , Philip Steelea , Hugh W. Reida , Mark P. Dagleisha , and Joaquín Castillab,c,g,2 a

Moredun Research Institute, Penicuik, Near Edinburgh EH26 0PZ, Scotland, United Kingdom; b CIC bioGUNE, Derio 48160, Bizkaia, Spain; g IKERBASQUE, Basque Foundation for Science, Bilbao 48011, Bizkaia, Spain; c Department of Infectology, Scripps Florida, Jupiter, FL 33458; f Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT 59840; d Centre de Recerca en Sanitat Animal (CReSA), UAB-IRTA, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain; and e Centro Nacional de Biotecnología (CNB), 28049 Cantoblanco, Madrid, Spain

Edited by Reed B. Wickner, National Institutes of Health, Bethesda, MD, and approved February 16, 2012 (received for review December 6, 2011)

The ability of prions to infect some species and not others is determined by the transmission barrier. This unexplained phenomenon has led to the belief that certain species were not susceptible to transmissible spongiform encephalopathies (TSEs) and therefore represented negligible risk to human health if consumed. Using the protein misfolding cyclic amplification (PMCA) technique, we were able to overcome the species barrier in rabbits, which have been classified as TSE resistant for four decades. Rabbit brain homogenate, either unseeded or seeded in vitro with disease-related prions obtained from different species, was subjected to serial rounds of PMCA. De novo rabbit prions produced in vitro from unseeded material were tested for infectivity in rabbits, with one of three intracerebrally challenged animals succumbing to disease at 766 d and displaying all of the characteristics of a TSE, thereby demonstrating that leporids are not resistant to prion infection. Material from the brain of the clinically affected rabbit containing abnormal prion protein resulted in a 100% attack rate after its inoculation in transgenic mice overexpressing rabbit PrP. Transmissibility to rabbits (>470 d) has been confirmed in 2 of 10 rabbits after intracerebral challenge. Despite rabbits no longer being able to be classified as resistant to TSEs, an outbreak of “mad rabbit disease” is unlikely.

snip...

In summary, after 3 y postchallenge with three different rabbitderived inocula, we have obtained one positive clinical case, one possible preclinical case, two intercurrent deaths, and six animals that have remained healthy. Although the incubation periods do not directly correlate with the degree of susceptibility, these data might indicate that rabbits are poorly susceptible to prion infection. Although the rabbits used in this study were not inbred, they all had identical full-length PrP sequences and, to date, no difference has been detected in the ORF PrP sequence in any other published rabbit PrP sequence placed in GenBank. To further investigate this, two types of second passage experiment were performed; three raPrPTg mice and 10 rabbits were all intracerebrally inoculated using brain homogenate from the clinically affected rabbit. In contrast to 100% of the de novo RaPrPSc-inoculated transgenic mice having succumbed to a standard clinical prion disease and thereby demonstrating a high rate of transmissibility in vivo, two of 10 rabbits developed a TSE (477 and 540 dpi, respectively) to date. A plausible explanation for the evident differences between these two transmission studies would be the high level of rabbit PrPC expression (4- to 6-fold) in the murine model. In addition, it is well known that even if overexpression does not increase susceptibility, it can significantly reduce the incubation time of disease (2). However, the two positive TSE cases in the second rabbit passage, even though 8 rabbits remained clinically normal at 560 dpi, have led us to conclude that rabbits can no longer be considered a prionresistant species. The long incubation times, even after a second passage, might be due to the presence of some unknown, and probably rare, susceptibility factor in rabbits, which may also be present, for example, in equids and canids.

To critically evaluate this risk, several experiments are currently underway to characterize this new prion disease in rabbits and other species to examine its ability to cross the species barrier. In addition, supplementary experiments have been initiated in rabbits and also in transgenic mice that overexpress rabbit PrPC, to evaluate their susceptibilities to other important prion diseases including CWD and BSE. There are several factors that any potential new TSE epidemic would require: (i) the new prion should be efficiently transmitted through the homologous species; (ii) animals should be edible by humans and should be slaughtered at an age at which the disease has developed, thereby increasing the chance that prions have replicated (especially for those prions that require long incubation times); and (iii) the meat and bone meal should be recycled and fed to new members of the same species. In the light of these data and taking into account the previous three factors, it is unlikely there will be an outbreak of “mad rabbit disease,” and consumers of rabbit meat face much less of a risk than consumers of cattle or sheep products.


THE USA FDA MAD COW FEED BAN OF 1997 WAS NOTHING MORE THAN INK ON PAPER, NEVER ENFORCED...terry

SUNDAY, SEPTEMBER 1, 2019 

FDA Reports on VFD Compliance

Before and after the current Veterinary Feed Directive (VFD) rules took full effect in January, 2017, the FDA focused primarily on education and outreach to help feed mills, veterinarians and producers understand and comply with the requirements. Since then, FDA has gradually increased the number of VFD inspections and initiated enforcement actions when necessary.


SATURDAY, DECEMBER 21, 2019 

In vitro detection of haematogenous prions in white-tailed deer orally dosed with low concentrations of chronic wasting disease


FRIDAY, DECEMBER 06, 2019 

Estimating relative CWD susceptibility and disease progression in farmed white-tailed deer with rare PRNP alleles


> However, to date, no CWD infections have been reported in people.
key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
Chronic Wasting Disease CWD TSE Prion aka mad deer disease zoonosis
We hypothesize that:
(1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues;
(2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence;
(3) Reliable essays can be established to detect CWD infection in humans; and
(4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches.
ZOONOTIC CHRONIC WASTING DISEASE CWD TSE PRION UPDATE
Prion 2017 Conference
First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1 
University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen 
This is a progress report of a project which started in 2009. 21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves. 
Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice. 
At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation. 
PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS 
PRION 2018 CONFERENCE
Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice
Hermann M. Schatzl, Samia Hannaoui, Yo-Ching Cheng, Sabine Gilch (Calgary Prion Research Unit, University of Calgary, Calgary, Canada) Michael Beekes (RKI Berlin), Walter Schulz-Schaeffer (University of Homburg/Saar, Germany), Christiane Stahl-Hennig (German Primate Center) & Stefanie Czub (CFIA Lethbridge).
To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years.
After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were detected in spinal cord and brain of some euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and pre-clinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles.
Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate.
The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.
Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP.
The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD..
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***
READING OVER THE PRION 2018 ABSTRACT BOOK, LOOKS LIKE THEY FOUND THAT from this study ;
P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States
Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1) (1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA..
SEEMS THAT THEY FOUND Highly endemic states had a higher rate of prion disease mortality compared to non-CWD
states.
AND ANOTHER STUDY;
P172 Peripheral Neuropathy in Patients with Prion Disease
Wang H(1), Cohen M(1), Appleby BS(1,2) (1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio..
IN THIS STUDY, THERE WERE autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017,
AND
included 104 patients. SEEMS THEY FOUND THAT The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%),
AND
THAT The Majority of cases were male (60%), AND half of them had exposure to wild game.
snip…
see more on Prion 2017 Macaque study from Prion 2017 Conference and other updated science on cwd tse prion zoonosis below…terry
PRION 2019 ABSTRACTS 

1. Interspecies transmission of the chronic wasting disease agent

Justin Greenlee

Virus and Prion Research Unit, National Animal Disease Center, USDA Agriculture Research Service

ABSTRACT

The presentation will summarize the results of various studies conducted at our research center that assess the transmissibility of the chronic wasting disease (CWD) agent to cattle, pigs, raccoons, goats, and sheep. This will include specifics of the relative attack rates, clinical signs, and microscopic lesions with emphasis on how to differentiate cross-species transmission of the CWD agent from the prion diseases that naturally occur in hosts such as cattle or sheep. Briefly, the relative difficulty of transmitting the CWD agent to sheep and goats will be contrasted with the relative ease of transmitting the scrapie agent to white-tailed deer.

53. Evaluation of the inter-species transmission potential of different CWD isolates

Rodrigo Moralesa, Carlos Kramma,b, Paulina Sotoa, Adam Lyona, Sandra Pritzkowa, Claudio Sotoa

aMitchell Center for Alzheimer’s disease and Related Brain Disorders, Dept. of Neurology, McGovern School of Medicine University of Texas Health Science Center at Houston, TX, USA; bFacultad de Medicina, Universidad de los Andes, Santiago, Chile

ABSTRACT

Chronic Wasting Disease (CWD) has reached epidemic proportions in North America and has been identified in South Korea and Northern Europe. CWD-susceptible cervid species are known to share habitats with humans and other animals entering the human food chain. At present, the potential of CWD to infect humans and other animal species is not completely clear. The exploration of this issue acquires further complexity considering the differences in the prion protein sequence due to species-specific variations and polymorphic changes within species. While several species of cervids are naturally affected by CWD, white-tailed deer (WTD) is perhaps the most relevant due to its extensive use in hunting and as a source of food. Evaluation of inter-species prion infections using animals or mouse models is costly and time consuming. We and others have shown that the Protein Misfolding Cyclic Amplification (PMCA) technology reproduces, in an accelerated and inexpensive manner, the inter-species transmission of prions while preserving the strain features of the input PrPSc. In this work, we tested the potential of different WTD-derived CWD isolates to transmit to humans and other animal species relevant for human consumption using PMCA. For these experiments, CWD isolates homozygous for the most common WTD-PrP polymorphic changes (G96S) were used (96SS variant obtained from a pre-symptomatic prion infected WTD). Briefly, 96GG and 96SS CWD prions were adapted in homologous or heterologous substrate by PMCA through several (15) rounds. End products, as well as intermediates across the process, were tested for their inter-species transmission potentials. A similar process was followed to assess seed-templated misfolding of ovine, porcine, and bovine PrPC. Our results show differences on the inter-species transmission potentials of the four adapted materials generated (PrPC/PrPSc polymorphic combinations), being the homologous combinations of seed/substrate the ones with the greater apparent zoonotic potential. Surprisingly, 96SS prions adapted in homologous substrate were the ones showing the easiest potential to template PrPC misfolding from other animal species. In summary, our results show that a plethora of different CWD isolates, each comprising different potentials for inter-species transmission, may exist in the environment. These experiments may help to clarify an uncertain and potentially worrisome public health issue. Additional research in this area may be useful to advise on the design of regulations intended to stop the spread of CWD and predict unwanted zoonotic events.

56. Understanding chronic wasting disease spread potential for at-risk species

Catherine I. Cullingham, Anh Dao, Debbie McKenzie and David W. Coltman

Department of Biological Sciences, University of Alberta, Edmonton AB, Canada

CONTACT Catherine I. Cullingham cathy.cullingham@ualberta.ca

ABSTRACT

Genetic variation can be linked to susceptibility or resistance to a disease, and this information can help to better understand spread-risk in a population. Wildlife disease incidence is increasing, and this is resulting in negative impacts on the economy, biodiversity, and in some instances, human health. If we can find genetic variation that helps to inform which individuals are susceptible, then we can use this information on at-risk populations to better manage negative consequences. Chronic wasting disease, a fatal, transmissible spongiform encephalopathy of cervids (both wild and captive), continues to spread geographically, which has resulted in an increasing host-range. The disease agent (PrPCWD) is a misfolded conformer of native cellular protein (PrPC). In Canada, the disease is endemic in Alberta and Saskatchewan, infecting primarily mule deer and white-tail deer, with a smaller impact on elk and moose populations. As the extent of the endemic area continues to expand, additional species will be exposed to this disease, including bison, bighorn sheep, mountain goat, and pronghorn antelope. To better understand the potential spread-risk among these species, we reviewed the current literature on species that have been orally exposed to CWD to identify susceptible and resistant species. We then compared the amino acid polymorphisms of PrPC among these species to determine whether any sites were linked to susceptibility or resistance to CWD infection. We sequenced the entire PrP coding region in 578 individuals across at-risk populations to evaluate their potential susceptibility. Three amino acid sites (97, 170, and 174; human numbering) were significantly associated with susceptibility, but these were not fully discriminating. All but one species among the resistant group shared the same haplotype, and the same for the susceptible species. For the at-risk species, bison had the resistant haplotype, while bighorn sheep and mountain goats were closely associated with the resistant type. Pronghorn antelope and a newly identified haplotype in moose differed from the susceptible haplotype, but were still closely associated with it. These data suggest pronghorn antelope will be susceptible to CWD while bison are likely to be resistant. Based on this data, recommendations can be made regarding species to be monitored for possible CWD infection.

KEYWORDS: Chronic wasting disease; Prnp; wildlife disease; population genetics; ungulates

Thursday, May 23, 2019 

Prion 2019 Emerging Concepts CWD, BSE, SCRAPIE, CJD, SCIENTIFIC PROGRAM Schedule and Abstracts


see full Prion 2019 Conference Abstracts

THURSDAY, OCTOBER 04, 2018
Cervid to human prion transmission 5R01NS088604-04 Update
*** now, let’s see what the authors said about this casual link, personal communications years ago, and then the latest on the zoonotic potential from CWD to humans from the TOKYO PRION 2016 CONFERENCE.

see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ???? “Our conclusion stating that we found no strong evidence of CWD transmission to humans”


Subject: CWD aka MAD DEER/ELK TO HUMANS ???

Date: September 30, 2002 at 7:06 am PST

From: "Belay, Ermias"

To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"

Sent: Monday, September 30, 2002 9:22 AM

Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Dear Sir/Madam,

In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD.. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091). Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.

Ermias Belay, M.D. Centers for Disease Control and Prevention

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

From: Sent: Sunday, September 29, 2002 10:15 AM


Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS

Sunday, November 10, 2002 6:26 PM .......snip........end..............TSS

Thursday, April 03, 2008

A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.

snip...

*** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,

snip... full text ; 


> However, to date, no CWD infections have been reported in people. 

sporadic, spontaneous CJD, 85%+ of all human TSE, just not just happen. never in scientific literature has this been proven.

if one looks up the word sporadic or spontaneous at pubmed, you will get a laundry list of disease that are classified in such a way;



key word here is 'reported'. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can't, and it's as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it's being misdiagnosed as sporadic CJD. ...terry 

*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***

*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).*** 




SATURDAY, FEBRUARY 23, 2019 

Chronic Wasting Disease CWD TSE Prion and THE FEAST 2003 CDC an updated review of the science 2019


TUESDAY, NOVEMBER 04, 2014 

Six-year follow-up of a point-source exposure to CWD contaminated venison in an Upstate New York community: risk behaviours and health outcomes 2005–2011

Authors, though, acknowledged the study was limited in geography and sample size and so it couldn't draw a conclusion about the risk to humans. They recommended more study. Dr. Ermias Belay was the report's principal author but he said New York and Oneida County officials are following the proper course by not launching a study. "There's really nothing to monitor presently. No one's sick," Belay said, noting the disease's incubation period in deer and elk is measured in years. "


***> In conclusion, sensory symptoms and loss of reflexes in Gerstmann-Sträussler-Scheinker syndrome can be explained by neuropathological changes in the spinal cord. We conclude that the sensory symptoms and loss of lower limb reflexes in Gerstmann-Sträussler-Scheinker syndrome is due to pathology in the caudal spinal cord. <***

***> The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.<*** 

***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***

***> All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals.<*** 

***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II) <***

 ***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***


Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.

https://www.nature.com/articles/srep11573 


O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations 

Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). 

Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods. 

*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period, 

***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014), 

***is the third potentially zoonotic PD (with BSE and L-type BSE), 

***thus questioning the origin of human sporadic cases. 

We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health. 

=============== 

***thus questioning the origin of human sporadic cases*** 

=============== 

***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals. 

============== https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf 

***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. 

***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20 

PRION 2016 TOKYO

Saturday, April 23, 2016

SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016

Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online

Taylor & Francis

Prion 2016 Animal Prion Disease Workshop Abstracts

WS-01: Prion diseases in animals and zoonotic potential

Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20

Title: Transmission of scrapie prions to primate after an extended silent incubation period) 

*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS. 

*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated. 

*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains. http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160

1: J Infect Dis 1980 Aug;142(2):205-8

Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to nonhuman primates.

Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.

Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were exposed to the infectious agents only by their nonforced consumption of known infectious tissues. The asymptomatic incubation period in the one monkey exposed to the virus of kuru was 36 months; that in the two monkeys exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively. Careful physical examination of the buccal cavities of all of the monkeys failed to reveal signs or oral lesions. One additional monkey similarly exposed to kuru has remained asymptomatic during the 39 months that it has been under observation.

snip...

The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie by natural feeding to squirrel monkeys that we have reported provides further grounds for concern that scrapie-infected meat may occasionally give rise in humans to Creutzfeldt-Jakob disease.

PMID: 6997404


Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates. One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the finding that some strains of scrapie produce lesions identical to the once which characterise the human dementias"

Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the acrapie problem urgent if the sheep industry is not to suffer grievously.

snip...

76/10.12/4.6


Nature. 1972 Mar 10;236(5341):73-4.

Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).

Gibbs CJ Jr, Gajdusek DC.

Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0

Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)

C. J. GIBBS jun. & D. C. GAJDUSEK

National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland

SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).



Wednesday, February 16, 2011

IN CONFIDENCE

SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE


A newly identified type of scrapie agent can naturally infect sheep with resistant PrP genotypes

Annick Le Dur*,?, Vincent Béringue*,?, Olivier Andréoletti?, Fabienne Reine*, Thanh Lan Laï*, Thierry Baron§, Bjørn Bratberg¶, Jean-Luc Vilotte?, Pierre Sarradin**, Sylvie L. Benestad¶, and Hubert Laude*,?? +Author Affiliations

*Virologie Immunologie Moléculaires and ?Génétique Biochimique et Cytogénétique, Institut National de la Recherche Agronomique, 78350 Jouy-en-Josas, France; ?Unité Mixte de Recherche, Institut National de la Recherche Agronomique-Ecole Nationale Vétérinaire de Toulouse, Interactions Hôte Agent Pathogène, 31066 Toulouse, France; §Agence Française de Sécurité Sanitaire des Aliments, Unité Agents Transmissibles Non Conventionnels, 69364 Lyon, France; **Pathologie Infectieuse et Immunologie, Institut National de la Recherche Agronomique, 37380 Nouzilly, France; and ¶Department of Pathology, National Veterinary Institute, 0033 Oslo, Norway

***Edited by Stanley B. Prusiner, University of California, San Francisco, CA (received for review March 21, 2005)

Abstract 

Scrapie in small ruminants belongs to transmissible spongiform encephalopathies (TSEs), or prion diseases, a family of fatal neurodegenerative disorders that affect humans and animals and can transmit within and between species by ingestion or inoculation. Conversion of the host-encoded prion protein (PrP), normal cellular PrP (PrPc), into a misfolded form, abnormal PrP (PrPSc), plays a key role in TSE transmission and pathogenesis. The intensified surveillance of scrapie in the European Union, together with the improvement of PrPSc detection techniques, has led to the discovery of a growing number of so-called atypical scrapie cases. These include clinical Nor98 cases first identified in Norwegian sheep on the basis of unusual pathological and PrPSc molecular features and "cases" that produced discordant responses in the rapid tests currently applied to the large-scale random screening of slaughtered or fallen animals. Worryingly, a substantial proportion of such cases involved sheep with PrP genotypes known until now to confer natural resistance to conventional scrapie. Here we report that both Nor98 and discordant cases, including three sheep homozygous for the resistant PrPARR allele (A136R154R171), efficiently transmitted the disease to transgenic mice expressing ovine PrP, and that they shared unique biological and biochemical features upon propagation in mice.

*** These observations support the view that a truly infectious TSE agent, unrecognized until recently, infects sheep and goat flocks and may have important implications in terms of scrapie control and public health.


SUNDAY, FEBRUARY 09, 2020 

Management of chronic wasting disease in ranched elk: conclusions from a longitudinal three-year study

Although the herd owners were presented with additional management directives, including culling of CWD positive bulls and those animals positive by an amplification assay (RT-QuIC), they were not implemented due to concern regarding its potential impact on hunting revenue. 


Terry S. Singeltary Sr.

posted by Terry S. Singeltary Sr. at 2:17 PM

0 Comments:

Post a Comment

Subscribe to Post Comments [Atom]

<< Home