SCIENTIFIC REPORT OF EFSA
Scientific and technical assistance on the provisional results of the study
on genetic resistance to Classical scrapie in goats in Cyprus1
European Food Safety Authority2, 3
European Food Safety Authority (EFSA), Parma, Italy
ABSTRACT
This EFSA Scientific Report reviews and discusses the provisional results
of a study (EURL/Cypriot study) on genetic resistance to Classical scrapie in
goats in Cyprus. It is concluded that the provisional results obtained in the
study further support the lower susceptibility to Classical scrapie in goats
carrying the D146 and S146 alleles compared to wild type (N146N) goats. The
results from intracerebral challenge are not compatible with a level of
resistance as high as the one observed in sheep carrying the ARR allele or in
goats carrying the K222 allele. Final results from the oral challenge will be
crucial in determining the level of resistance associated with the D146 and S146
alleles. Furthermore, it is concluded that the provisional results obtained in
the study are compatible with the possibility to use the D146 and S146 alleles
to build a genetic strategy to control and eradicate Classical scrapie in goats
in Cyprus. However, the success of such a strategy will be determined by the
level of resistance associated with the D146 and S146 alleles against infection
with all the different TSE agents proved to be circulating in Cyprus, which at
this stage of the EURL/Cypriot study remains to be definitively assessed. In
addition, as compared to the results of the model developed in the study, it is
concluded that the efficiency of the implementation in the field of a breeding
strategy selecting for the D146 and S146 alleles may be lower due to potential
practical constraints related to the management of genetic diversity, to the
selection for production and health traits and to the need of moving animals for
breeding purposes in Cyprus. Recommendations on aspects that may be considered
when completing the study are formulated.
© European Food Safety Authority, 2012
KEY WORDS
TSE, Classical scrapie, goat, genetic resistance, breeding programme,
Cyprus.
snip...
Interim Conclusions
The oral challenge studies, the management cull and the whole herd cull
data all support the previously published field observations that on one side
the genotype N146N is particularly associated with scrapie susceptibility and on
the other side the genotypes N146D, N146S, D146D, D146S and S146S are associated
with a degree of resistance.
All genotypes can succumb to challenge by the intracerebral route, but the
resulting phenotype is different when comparing the animals carrying genotype
N146N with all the others (most notably, no detection of PrPSc in the periphery
of infected animals with all the non-N146N-genotypes).
It is important that the oral challenges are continued to endpoint to
establish the relative resistance of other genotypes to challenge by this more
natural route Appendix A to Scientific Report of EFSA, EFSA Journal
2012;10(11):2972
Cyprus/EURL resistance in goats protocol Report May 2012
Page 13 of 13
All components of the study reinforce previously published UK caprine data3
which indicates that the current ELISA rapid test screen has considerably lower
sensitivity (approx 50%) than immunohistochemistry.
The wider issue of discriminatory testing for BSE vs scrapie may need to be
reviewed (regardless of genotype), since data from these studies suggest that
direct extrapolation from ovine data may not be appropriate for all caprine
isolates.
The TSE European Union Reference Laboratory at the Animal Health and
Veterinary Laboratory Agency New Haw, UK
The Government Veterinary Services, Cyprus
May 2012
Wednesday, January 18, 2012
BSE IN GOATS CAN BE MISTAKEN FOR SCRAPIE
February 1, 2012
posted January 18, 2012
BSE in goats can be mistaken for scrapie
Bovine spongiform encephalopathy in goats could be misdiagnosed as scrapie
in the absence of appropriate discriminatory tests, and such misidentification
occurred at least once before such tests were developed, according to a report
released in December.
The article, "Isolation of prion with BSE properties from farmed goat"
(Emerging Infectious Diseases 2011;17:2253-2261), indicates BSE can affect small
ruminants under natural conditions and that the condition can be misdiagnosed.
The agent that causes scrapie is not known to infect humans, but consumption of
beef contaminated with the prions that cause BSE is connected with variant
Creutzfeldt-Jakob disease, a neurodegenerative disorder in humans.
The report calls for continued extensive surveillance and breeding plans to
prevent BSE outbreaks among small ruminants. Such outbreaks could harm public
health.
The authors stated in the text that the misdiagnosis occurred in 1990 in
the United Kingdom. The case had been identified as suspected BSE in 2006
because differential immunohistochemical analysis of fixed brain tissue produced
a signature indistinguishable from BSE. The authors of the recent report used a
bioassay to confirm the BSE diagnosis.
The sample collected in 1990 was among 26 historic samples collected from
1984-2002, the report states.
The report indicates the U.K. goat and a goat in France found to have BSE
in 2005 both likely became infected through contaminated food supplements.
While BSE lesions are contained mainly within nervous tissue in cattle, the
report states "in small ruminants the BSE agent is widely distributed in
peripheral tissues and can be transmitted horizontally." Feed ban measures alone
would be insufficient for controlling a BSE outbreak in small ruminants,
according to the report.
"Also, it would be impossible to prevent BSE from entering the human food
chain through consumption of food products derived from small ruminants," the
report states.
Discussion
We confirmed that the agent responsible for TSE in a UK goat, which was
initially reported as scrapie in 1990 and subsequently as suspected BSE in 2006
(16), was a BSE agent. This conclusion was based on bioassay of nervous tissue
in mice demonstrating similarities of histopathologic lesions, PrPSc mapping in
the brain, and WB of PrPSc with those of mice inoculated with BSE from various
ovine, caprine, and bovine sources.
Saturday, December 3, 2011
Isolation of Prion with BSE Properties from Farmed Goat Volume 17, Number
12—December 2011
snip...see full text ;
Scientific Opinion on genetic TSE resistance in goats in all European Union
Member States Question number: EFSA-Q-2009-00448
Adopted: 21 October 2009 Summary (0.1Mb)
Opinion (0.3Mb)
Summary
Following a request from the European Commission, the Panel on Biological
Hazards (BIOHAZ) was asked to deliver a scientific opinion on genetic resistance
to Transmissible Spongiform Encephalopathies (TSE) in goats.
For a first part of that request, the BIOHAZ Panel adopted on 5th March
2009 a scientific opinion on the scientific validity of a study carried out by
the Cypriot authorities under the auspices of the Community Reference Laboratory
(CRL) for TSEs. That scientific opinion also indicated to what extent the
information contained in the study could be used as relevant tools to control
Classical scrapie in Cyprus.
In the current scientific opinion the BIOHAZ Panel addresses genetic
resistance as a relevant tool for breeding for resistance to all TSEs of goats
(including Atypical scrapie and BSE) in all the Member States (MSs) (except for
Classical scrapie in Cyprus).
To carry out this task, available scientific knowledge on genetic TSE
resistance in goats in the EU is reviewed, addressing those PRNP polymorphisms
for which a capacity to provide resistance to TSEs in goats has been (or is
being) investigated. Details tailored to the different TSEs found in this small
ruminants (i.e. Classical scrapie, Atypical scrapie and BSE) are also considered
and presented.
Further on, the feasibility of a large-scale breeding program in animal
populations would need to be supported by a sound logistical and technical
infrastructure in any given territory. In order to collect preliminary data that
could help to evaluate the specific situation in the different EU MSs, a
questionnaire was developed and circulated among the EFSA BSE-TSE Network. The
results of the analysis of the replies received are also presented
herewith.
The BIOHAZ Panel concluded that there are encouraging but as yet incomplete
data to consider supporting a breeding programme for resistance in goats against
Classical scrapie in all EU MSs, and ongoing studies are expected to provide a
more robust scientific background in the coming years. On the other hand, at
this moment there are not enough data available to consider supporting a
breeding programme for resistance against Atypical scrapie and BSE in goats in
all EU MSs. Experiments are ongoing on BSE in goats and results will be
available in the next years. Furthermore, there are limited data suggesting that
an allele (H154) might confer resistance to Classical scrapie but increase
susceptibility to Atypical scrapie.
The frequency of the wild type allele, which is known to confer
susceptibility to Classical scrapie, is high in all goat breeds considered.
Thus, selection for putative resistance alleles will be slow, complicated and
highly dependent on breeding structure.
It is acknowledged that any large scale breeding programme for TSE
resistance in goats must take into consideration key elements related to the
current dissemination of potentially TSE protective polymorphisms in the goat
population of each EU MS and the characterisation of the real protection
provided by those polymorphisms. At present, only a few EU MSs seem to have in
place the necessary elements to introduce a breeding for resistance programme
for Classical scrapie in goats.
The BIOHAZ Panel makes a series of recommendations on new investigations in
order to assess the efficacy of breeding for the candidate PRNP alleles as a
mean to control TSEs in goats. Furthermore, research on the possible adverse
effects of the candidate PRNP polymorphisms on other production traits should be
encouraged. In addition, it is recommended that a breeding for resistance
programme for TSE in goats is first implemented in the seven EU MSs with the
largest goat population as this would have the most impact.
Published: 9 November 2009
OPINION
Tuesday, November 10, 2009
A retrospective immunohistochemical study reveals atypical scrapie has
existed in the United Kingdom since at least 1987
Brief Research Reports
-------- Original Message --------
Subject: Twelve Greek goats were found to be suffering from the
brain-wasting disease scrapie in the first half of 2004
Date: Wed, 19 Jan 2005 13:30:26 –0600
From: "Terry S. Singeltary Sr."
To: Bovine Spongiform Encephalopathy
CC: cjdvoice@yahoogroups.com
Wednesday January 19, 2005
Brain disease in Greek goats
Twelve Greek goats were found to be suffering from the brain-wasting
disease scrapie in the first half of 2004, EU figures made public yesterday
reveal.
The data, issued by the European Food Safety Authority (EFSA), show that 12
cases of transmissible spongiform encephalopathies (TSE) were discovered in
Greece, eight in Cyprus and 26 in France out of some 17,294 goats tested
throughout the EU in 2004. The figures were made public by Left Coalition
Synaspismos MEP Dimitris Papadopoulos.
Some 100 Europeans have died from the human form of bovine spongiform
encephalopathy (BSE), or mad cow disease, a strain of the TSE group.
Meanwhile, tests are continuing in the case of a French goat slaughtered in
2002, which experts think may have developed BSE. The EU bans the use of milk
and meat from herds affected by a TSE case.
TSS
-------- Original Message --------
Subject: Twelve Greek goats were found to be suffering from the
brain-wasting disease scrapie in the first half of 2004
Date: Wed, 19 Jan 2005 13:30:26 –0600
From: "Terry S. Singeltary Sr."
To: Bovine Spongiform Encephalopathy
CC: cjdvoice@yahoogroups.com
Wednesday January 19, 2005
Brain disease in Greek goats
Twelve Greek goats were found to be suffering from the brain-wasting
disease scrapie in the first half of 2004, EU figures made public yesterday
reveal.
The data, issued by the European Food Safety Authority (EFSA), show that 12
cases of transmissible spongiform encephalopathies (TSE) were discovered in
Greece, eight in Cyprus and 26 in France out of some 17,294 goats tested
throughout the EU in 2004. The figures were made public by Left Coalition
Synaspismos MEP Dimitris Papadopoulos.
Some 100 Europeans have died from the human form of bovine spongiform
encephalopathy (BSE), or mad cow disease, a strain of the TSE group.
Meanwhile, tests are continuing in the case of a French goat slaughtered in
2002, which experts think may have developed BSE. The EU bans the use of milk
and meat from herds affected by a TSE case.
TSS
Comment from Terry S Singeltary, CJD WATCH/VOICE
| Document ID: APHIS-2007-0033-0002 | Document Type: Public Submission |
|
This is comment on
Proposed Rule: Agricultural Bioterrorism Protection Act of 2002;
Biennial Review and Republication of the Select Agent and Toxin
List
Docket ID:
|
RIN:0579-AC53 |
Topics: No Topics associated with this
document
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Document:
snip...
Under APHIS-PPQ’s agriculture quarantine inspection monitoring, 584 air
passengers from Greece were sampled for items of agricultural interest in fiscal
year 2000. Of these passengers, 14 carried meat (non-pork) items that could
potentially transmit pathogens that cause BSE; most passengers carried from one
to two kilograms (kg) of meat, although one passenger in November 1999 carried
23 kg of meat in a suitcase. Florida, Massachusetts, and New York were the
reported destinations of these passengers. None of the passengers with meat
items reported plans to visit or work on a ranch or farm while in the US.
Source: US Department of Transportation, and APHIS-PPQ Agricultural
Quarantine Inspection data base
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