##################### Bovine Spongiform Encephalopathy #####################
From: TSS ()
Subject: Sheep can pass BSE to their lambs
Date: September 2, 2005 at 7:56 pm PST
Sheep can pass BSE to their lambs
16:34 17 August 2005
NewScientist.com news service
Debora MacKenzie
BSE has been shown to spread naturally between sheep for the first time. It passed from mother to lamb, before or during birth, in an experimentally infected flock. But if the study shows the infection spreads more generally within the flock, that means BSE could still be lurking in Europe's sheep, possibly posing a greater health risk to people than that from "mad" cows.
Scientists found in 1996 that sheep develop a disease similar to BSE if they eat infected cattle tissue. But feeding cattle remains to sheep was banned in Britain in 1988, and in the EU in 1994. All the sheep infected before then should be gone by now.
So there should be no more BSE sheep – unless they can transmit BSE to each other. Cattle cannot do this, but sheep transmit a related disease called scrapie between themselves, apparently when they eat placentas and other birthing remains in the field. If BSE also spreads "horizontally" in this way – between other members of the flock – it might have kept spreading in sheep even after the feed ban.
And because the symptoms of BSE in sheep resemble scrapie, "mad" sheep might not have been noticed. Nearly 2700 sheep with apparent scrapie have now been tested for BSE in the UK. None so far had clear BSE, though two are being tested further. BSE-infected goats, which are biologically similar to sheep, were found in France and possibly the UK in 2005.
BSE-infected sheep are potentially more dangerous to human consumers than BSE-infected cows, as they carry the infection in more of the tissues people eat.
Mother to lamb
Sue Bellworthy and colleagues at the UK's Veterinary Laboratories Agency (VLA) report that two ewes experimentally infected with BSE in a flock in Warwickshire in 2000 gave birth to lambs in 2003 that died of BSE this year. This is the first confirmation of "vertical" transmission of BSE from mother to offspring. It has been suspected but never proved in cattle.
In sheep, given how scrapie spreads, "this was expected," Danny Matthews, a BSE expert at the VLA, told New Scientist. "But vertical transmission alone would not be enough to keep BSE going in the sheep population after the feed ban." Transmission would be limited to one family line, which would die out as animals die of BSE or are eaten.
The experimental herd is now being watched to see if adults can transmit BSE horizontally to other ewe's lambs now being born and raised within the flock. So far none has, and no uninfected adult sheep have caught the disease from experimentally infected sheep. But it's still "too early to say", cautions Matthews.
Journal reference: Veterinary Record (Aug 13, p 206)
BSE and vCJD - Learn more in our comprehensive special report.
http://www.newscientist.com/channel/health/bse/dn7861
British goat may have harboured BSE
18:34 08 February 2005
NewScientist.com news service
Debora MacKenzie
A British goat which died in 1990 may have had BSE, UK government officials revealed on Tuesday. The discovery means the infection may have circulated in goats in the past, and may even be circulating at low levels today.
This follows the recent disclosure of the first natural case of BSE to be found in a goat - a French animal that died in 2002. New Scientist has learned that the British goat was discovered as a result of the French case, as UK government scientists prepared for the increased testing of goats after the discovery.
It has long been assumed that sheep and goats may have been exposed to BSE in feed made from infected cattle. But unlike cattle, both creatures can transmit such infections between individuals, which might have kept the disease circulating after infected feed was banned.
BSE in sheep and goats would also be hard to spot, as both can naturally develop a similar disease called scrapie which has the same symptoms, although it is not thought to pose a risk to human consumers. And, unlike cattle, sheep experimentally infected with BSE carry the infectious prion in muscle meat, so the infection in sheep and goats could pose more of a risk to consumers.
For these reasons European Union countries have been testing sheep and goats for BSE since 2002. These tests discovered the infected French goat.
Telling the difference
"We were involved in helping evaluate the French data in December," says Danny Matthews of the UK's Veterinary Laboratories Agency, the EU reference lab for BSE. It was clear that the EU would probably ask for increased testing in goats as a result, he says.
In fact, from February, 80% of healthy slaughtered goats over the age of 18 months, plus "high risk" goats such as those found dead or unable to stand, should be tested, officials have just agreed. Three different test methods - called western blot, ELISA and immunohistochemistry (IHC) - will be used to distinguish scrapie from BSE.
"We haven't had to test many goats in the UK," says Matthews. "We thought we should test our current IHC on goat brain to make sure it distinguishes BSE." Besides goats and sheep experimentally infected with scrapie or BSE, they tested two brain samples at random from within a selection of goats thought to have died of scrapie.
One of them gave an IHC result that looked like BSE. "We can't do the other two tests as we processed all the tissue we had from that animal for IHC," says Matthews. But the team will nevertheless attempt to extract enough tissue from the IHC test material to do the definitive BSE test. This involves injecting tissue into mouse brain to see if BSE develops. But that will not yield results for two years.
"What is important now is not what happened back in 1990, but whether the infection is still circulating in goats," notes Matthews.
http://www.newscientist.com/channel/health/dn6987
Like lambs to the slaughter
* 31 March 2001
* Debora MacKenzie
* Magazine issue 2284
Suspect symptoms
What if you can catch old-fashioned CJD by eating meat from a sheep infected with scrapie?
Exclusive from New Scientist magazine
Four years ago, Terry Singeltary watched his mother die horribly from a degenerative brain disease. Doctors told him it was Alzheimer's, but Singeltary was suspicious. The diagnosis didn't fit her violent symptoms, and he demanded an autopsy. It showed she had died of sporadic Creutzfeldt-Jakob disease.
Photo: Murdo McLeod
Most doctors believe that sCJD is caused by a prion protein deforming by chance into a killer. But Singeltary thinks otherwise.
He is one of a number of campaigners who say that some sCJD, like the variant CJD related to BSE, is caused by eating meat from infected animals. Their suspicions have focused on sheep carrying scrapie, a BSE-like disease that is widespread in flocks across Europe and North America.
Now scientists in France have stumbled across new evidence that adds weight to the campaigners' fears. To their complete surprise, the researchers found that one strain of scrapie causes the same brain damage in mice as sCJD.
"This means we cannot rule out that at least some sCJD may be caused by some strains of scrapie," says team member Jean-Philippe Deslys of the French Atomic Energy Commission's medical research laboratory in Fontenay-aux-Roses, south-west of Paris.
Hans Kretschmar of the University of Göttingen, who coordinates CJD surveillance in Germany, is so concerned by the findings that he now wants to trawl back through past sCJD cases to see if any might have been caused by eating infected mutton or lamb.
Brain damage
Scrapie has been around for centuries and until now there has been no evidence that it poses a risk to human health. But if the French finding means that scrapie can cause sCJD in people, countries around the world may have overlooked a CJD crisis to rival that caused by BSE.
Deslys and colleagues were originally studying vCJD, not sCJD. They injected the brains of macaque monkeys with brain from BSE cattle, and from French and British vCJD patients. The brain damage and clinical symptoms in the monkeys were the same for all three. Mice injected with the original sets of brain tissue or with infected monkey brain also developed the same symptoms.
As a control experiment, the team also injected mice with brain tissue from people and animals with other prion diseases: a French case of sCJD; a French patient who caught sCJD from human-derived growth hormone; sheep with a French strain of scrapie; and mice carrying a prion derived from an American scrapie strain.
As expected, they all affected the brain in a different way from BSE and vCJD. But while the American strain of scrapie caused different damage from sCJD, the French strain produced exactly the same pathology.
Multiple strains
"The main evidence that scrapie does not affect humans has been epidemiology," says Moira Bruce of the neuropathogenesis unit of the Institute for Animal Health in Edinburgh, who was a member of the same team as Deslys.
"You see about the same incidence of the disease everywhere, whether or not there are many sheep, and in countries such as New Zealand with no scrapie," she says. In the only previous comparisons of sCJD and scrapie in mice, Bruce found they were dissimilar.
But there are more than 20 strains of scrapie, and six of sCJD. "You would not necessarily see a relationship between the two with epidemiology if only some strains affect only some people," says Deslys. Bruce is cautious about the mouse results, but agrees they require further investigation. Other trials of scrapie and sCJD in mice, she says, are in progress.
Deformed proteins
People can have three different genetic variations of the human prion protein, and each type of protein can fold up two different ways. Kretschmar has found that these six combinations correspond to six clinical types of sCJD: each type of normal prion produces a particular pathology when it spontaneously deforms to produce sCJD.
But if these proteins deform because of infection with a disease-causing prion, the relationship between pathology and prion type should be different, as it is in vCJD. "If we look at brain samples from sporadic CJD cases and find some that do not fit the pattern," says Kretschmar, "that could mean they were caused by infection."
There are 250 deaths per year from sCJD in the US, and a similar incidence elsewhere. Singeltary and other US activists think that some of these people died after eating contaminated meat or "nutritional" pills containing dried animal brain.
Governments will have a hard time facing activists like Singeltary if it turns out that some sCJD isn't as spontaneous as doctors have insisted.
Deslys's work on macaques also provides further proof that the human disease vCJD is caused by BSE. And the experiments showed that vCJD is much more virulent to primates than BSE, even when injected into the bloodstream rather than the brain. This, says Deslys, means that there is an even bigger risk than we thought that vCJD can be passed from one patient to another through contaminated blood transfusions and surgical instruments.
More at: Proceedings of the National Academy of Sciences (vol 98, p 4142)
http://www.pnas.org/cgi/content/full/041490898v1
Correspondence about this story should be directed to [email protected]
1900 GMT, 28 March 2001
* New Scientist
http://www.newscientist.com/channel/health/bse/mg16922840.300
12/10/76
AGRICULTURAL RESEARCH COUNCIL
REPORT OF THE ADVISORY COMMITTE ON SCRAPIE
Office Note
CHAIRMAN: PROFESSOR PETER WILDY
snip...
A The Present Position with respect to Scrapie
A] The Problem
Scrapie is a natural disease of sheep and goats. It is a slow
and inexorably progressive degenerative disorder of the nervous system
and it ia fatal. It is enzootic in the United Kingdom but not in all
countries.
The field problem has been reviewed by a MAFF working group
(ARC 35/77). It is difficult to assess the incidence in Britain for
a variety of reasons but the disease causes serious financial loss;
it is estimated that it cost Swaledale breeders alone $l.7 M during
the five years 1971-1975. A further inestimable loss arises from the
closure of certain export markets, in particular those of the United
States, to British sheep.
It is clear that scrapie in sheep is important commercially and
for that reason alone effective measures to control it should be
devised as quickly as possible.
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
http://www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf
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.
PMID: 6997404
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract
Adaptation of the bovine spongiform encephalopathy agent to primates
and comparison with Creutzfeldt- Jakob disease: Implications for
human health
THE findings from Corinne Ida Lasmézas*, [dagger] , Jean-Guy Fournier*,
Virginie Nouvel*,
Hermann Boe*, Domíníque Marcé*, François Lamoury*, Nicolas Kopp [Dagger
] , Jean-Jacques Hauw§, James Ironside¶, Moira Bruce [||] , Dominique
Dormont*, and Jean-Philippe Deslys* et al, that The agent responsible
for French iatrogenic growth hormone-linked CJD taken as a control is
very different from vCJD but is similar to that found in one case of
sporadic CJD and one sheep scrapie isolate;
http://www.pnas.org/cgi/content/full/041490898v1
0208h023: UK exports of sheep, goats and sheep/goat meats and meat products (1988 - 2001)
http://www.vegsource.com/articles/sheep_exports.htm
TSS
Link: 0208h023: UK exports of sheep, goats and sheep/goat meats and meat products (1988 - 2001)
#################### https://lists.aegee.org/bse-l.html ####################
Veterinary Services
Centers for Epidemiology and Animal Health March 2004
____________________________________________________________________________
_____________________________________________
Highlights of Phase II: Scrapie:
Ovine Slaughter Surveillance
Study 2002-2003
The purpose of the SOSS study was to estimate
the regional and national prevalence of scrapie in
mature cull sheep in the United States.
Phase I of SOSS was conducted from February
2001 through March 2002 and included refinement
of the study design and sample collection training.
The purpose of Phase I was to develop and modify
the sample collection and testing processes,
without emphasizing statistical results.
SOSS Phase II is similar to Phase I in that
sample collection procedures and testing were
used, along with a representative sample
allocation. Beginning April 1, 2002, and continuing
through March 31, 2003, Phase II included the
collection of tissue samples from 12,508 sheep
from 22 slaughter plants throughout the United
States (21 FSIS inspected, 1 State plant) and 1
large livestock market in Texas. The 21 FSIS plants
represented approximately two-thirds of the total
FSIS mature sheep slaughtered during the study
period. The livestock market represented
approximately one-half of the live sheep exported
to Mexico. All sample data were statistically
weighted to reflect the population from which the
sample was selected. The number of samples
collected from each plant on a specific day was
statistically weighted to represent the volume of
mature sheep slaughtered (sold) through each
plant (market) that specific day. This weight was
adjusted for the total volume of mature sheep
through the plant (market) from April 2002 through
March 2003. Within each facility sample collectors
were instructed to collect samples using systematic
sampling. Overall, the samples collected from the
22 plants and the livestock market represented
299,000 sheep (54 percent of the cull sheep
population, estimated at 550,000 head).
Sheep were traced to State of origin based on
ear tags and/or other information obtained by the
collector at the plant or market. For analysis
purposes, samples identified to individual States
were assigned to one of four defined regions.
Sometimes only a listing of multiple States could be
obtained for a group of sheep (e.g., market animals
accumulated across numerous States). These
samples were assigned to the Multiregion category
if the States they came from were not all in the
same region. In cases where a trace State was not
identified by the collector (n = 2,020), a region was
assigned based on their official identification
information. The 2001 NAHMS Sheep study
showed that at least 95 percent of cull sheep
movement was within the region of origin. Out of
the 12,508 samples submitted, all but 2,127 were
identified to a unique region (Table 1).
Table 1. Number of Samples Submitted, by Face Color
and By Region.
Samples Submitted
Region
Face
Color West Mountain Central East
Multiregion
Total
Black 100 535 680 1,023 453 2,791
White 493 2,997 1,993 1,283 1,472 8,238
Mottled 71 305 413 404 194 1,387
Unknown 6 32 4 42 8 92
Total 670 3,869 3,090 2,752 2,127 12,508
Obex, tonsil, and lymph-node tissues from each
sheep were tested using the immunohistochemistry
(IHC) technique at the National Veterinary Services
Laboratory. A positive case was defined as having
a positive test result on any tissue.
United States Department of Agriculture • Animal and Plant Health Inspection
Service • Safeguarding American Agriculture
Prior to the SOSS study, the estimated
pre as 0.07
p '96
spected
'96
hlights were excerpted from
Pha
revalence estimates
Of the 12,508 mature sheep sampled, valid (at
itive
0.20
s
.
Three tissue types (obex, tonsil, and
llected
in
s
valence of scrapie in the United States w
percent (based on unpublished data from the
NAHMS Sheep '96 study). However, the Shee
estimate was based on a mail-in survey of
producers who reported the presence of su
or confirmed cases of scrapie in their flock over a
period of 5 years, including lambs and mature
sheep. The flock estimate was then expanded
based on flock size to generate the animal-leve
prevalence estimate. The results of the SOSS
study cannot be directly compared to the Sheep
prevalence estimate because of differences in
study design, reference population, and data
collection methods.
The following hig
l
se II: Scrapie: Ovine Slaughter Surveillance
Study 2002-2003.
P
•
least one testable tissue) test results were
obtained from 12,491 (99.9 percent). A pos
result was recorded for any animal that tested
positive by IHC on one or more of the tissues
sampled. The overall weighted national
prevalence of scrapie in mature sheep is
percent. Estimates could not be made in the
West region due to the low number of sample
obtained. However, national estimates include
samples collected in the West region (Figure 1)
•
retropharyngeal lymph node) were co
from each sheep head for IHC testing. As
expected, each tissue type differed slightly
the number tested as well as the number of
positive results; however, the prevalence wa
similar for the three tissue types (Figure 2).
0.0
0.2
0.4
0.6
Figure 2. Percent of Sheep That Tested Positive for Scrapie,
by Tissue Type
Percent
Tissue Type
Obex Tonsil Retropharyngeal
lymph node
0.18 0.19 0.20
Scrapie prevalence (one or more tissue
lack-
ot
•
samples tested positive) was highest in b
faced sheep (0.84 percent). White-faced sheep
were far less likely to test positive for scrapie
(less than 0.01 percent). Some animals were
presented for sample collection with the skin
removed. Therefore, face color could not be
determined on these animals and they were n
included in these estimates (Figure 3).
West Mountain Central East
United States Department of Agriculture • Animal and Plant Health Inspection
Service • Safeguarding American Agriculture
0.0
0.2
0.4
0.6
0.8
1.0
Percent
Face Color
Figure 3. Percent of Sheep That Tested Positive for Scrapie,
by Face Color
0.00
0.84
0.12
White Black Mottled
p
t of
,
Age was determined based on the number of
•• visible permanent incisors. Four-year-old shee
tested positive (one or more tissue samples
tested positive) most frequently (0.49 percen
sheep tested). Scrapie prevalence increased
with age until the animals reached 4 years old
then decreased (Figure 4).
0.0
0.5
1.0
1.5
2.0
Black-faced sheep
National
Figure 4. Percent of Sheep That Tested Positive for Scrapie
(National and Black-faced Sheep), by Age
Percent
Age
0.11
0.00
0.21
0.54 0.49
1.77
0.13
0.69
1 and 2 years 3 years 4 years 5 years or more
enetics
ue samples from the 33 sheep that tested
pos
e at
______________________________
or more information, contact:
E7
G
Tiss
itive for scrapie were submitted for genetic
testing. All 33 samples were of the QQ genotyp
codon 171. This genotype has been characterized
as the least resistant to scrapie.
__
F
SDA:APHIS:VS:CEAH U
NRRC Building B, M.S. 2
2150 Centre Avenue
-8117 Fort Collins, CO 80526
970.494.7000
[email protected] E-mail: NAHMS
www.aphis.usda.gov/vs/ceah/cahm
N421.0304 #
____________________________________
) prohibits discrimination in
plaint of discrimination, write USDA, Director, Office of
yer.
ention of companies or commercial products does not imply
s nor
he U.S. Department of Agriculture (USDA T
all its programs and activities on the basis of race, color, national
origin, sex, religion, age, disability, political beliefs, sexual
orientation,
or marital status or family status. (Not all prohibited bases apply to all
programs.) Persons with disabilities who require alternative means for
communication of program information (Braille, large print, audiotape,
etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice
and TDD).
o file a com T
Civil Rights, Room 326-W, Whitten Building, 1400 Independence
Avenue, SW, Washington, DC 20250-9410 or call (202) 720-5964
(voice and TDD). USDA is an equal opportunity provider and emplo
M
recommendation or endorsement by the U.S. Department of
Agriculture over others not mentioned. USDA neither guarantee
warrants the standard of any product mentioned. Product names are
mentioned solely to report factually on available data and to provide
specific information.
United States Department of Agriculture • Animal and Plant Health Inspection
Service • Safeguarding American Agriculture
http://www.aphis.usda.gov/vs/ceah/ncahs/nahms/sheep/SOSS_highlights.pdf
Animal and
Plant Health
Inspection
SOSS
Phase II: Scrapie: Ovine Slaughter Surveillance
Study 2002-2003
snip...
Section I: Prevalence Estimates
A. Weighted Test
Results
1. Overall prevalence
Of the 12,508 mature sheep sampled, valid (at least one testable tissue)
test
results were obtained from 12,491 (99.9 percent). A positive result was
recorded for any animal that tested positive by immunohistochemistry (IHC)
on
one or more of the tissues sampled. The overall weighted national
prevalence of scrapie in mature sheep is 0.20 percent. Estimates could not
be
made in the West region due to the low number of samples obtained. However,
national estimates include samples collected in the West region.
a. Percentage of sheep that tested positive for scrapie, by region*:
Percent Sheep
Region
Mountain Central East Multiregion National
Pct.
Std.
Error Pct.
Std.
Error Pct.
Std.
Error Pct.
Std.
Error Pct.
Std.
Error
0.14 (0.06) 0.21 (0.10) 0.52 (0.15) 0.13 (0.07) 0.20 (0.04)
*Because of the low number of samples obtained in the West region, results
for the
West region are included in the National estimates but are not listed
individually.
snip...
http://www.aphis.usda.gov/vs/ceah/ncahs/nahms/sheep/SOSSphase2.pdf
TSS
----- Original Message -----
From: "Terry S. Singeltary Sr." <[email protected]>
To: <[email protected]>
Sent: Wednesday, August 24, 2005 9:11 PM
Subject: SCRAPIE USA UPDATE MARCH - JUNE 2005
##################### Bovine Spongiform Encephalopathy
#####################
From: TSS ()
Subject: SCRAPIE USA UPDATE MARCH - JUNE 2005
Date: August 24, 2005 at 7:03 pm PST
SCRAPIE USA MONTHLY REPORT 2005
AS of March 31, 2005, there were 70 scrapie infected source flocks (Figure
3). There were 11 new infected and source flocks reported in March (Figure
4) with a total of 51 flocks reported for FY 2005 (Figure 5). The total
infected and source flocks that have been released in FY 2005 are 39 (Figure
6), with 1 flock released in March. The ratio of infected and source flocks
released to newly infected and source flocks for FY 2005 = 0.76 : 1. IN
addition, as of March 31, 2005, 225 scrapie cases have been confirmed and
reported by the National Veterinary Services Laboratories (NVSL), of which
53 were RSSS cases (Figure 7). This includes 57 newly confirmed cases in
March 2005 (Figure 8). Fourteen cases of scrapie in goats have been reported
since 1990 (Figure 9). The last goat cases was reported in January 2005. New
infected flocks, source flocks, and flocks released or put on clean-up plans
for FY 2005 are depicted in Figure 10. ...
FULL TEXT ;
http://www.aphis.usda.gov/vs/nahps/scrapie/monthly_report/monthly-report.htm
l
SCRAPIE USA JUNE 2005 UPDATE
AS of June 30, 2005, there were 114 scrapie infected and source flocks
(Figure 3). There were 14 new infected and source flocks reported in June
(Figure 4) with a total of 123 flocks reported for FY 2005 (Figure 5).
snip...
In addition, as of June 30, 2005, 448 scrapie cases have been confirmed and
reported by the National Veterinary Services Laboratories (NVSL), of which
106 were RSSS cases (Figure 7). This includes 81 newly confirmed cases in
June 2005 (Figure 8). Fifteen cases of scrapie in goats have been reported
since 1990 (Figure 9). The last goat case was reported in May 2005.
snip...end
http://www.aphis.usda.gov/vs/nahps/scrapie/monthly_report/monthly-report.htm
l
USDA/APHIS
SOSS
Phase II: Scrapie: Ovine Slaughter Surveillance
Study 2002-2003
http://www.aphis.usda.gov/vs/ceah/ncahs/nahms/sheep/SOSSphase2.pdf
From: TSS ()
Subject: Sheep can pass BSE to their lambs
Date: September 2, 2005 at 7:56 pm PST
Sheep can pass BSE to their lambs
16:34 17 August 2005
NewScientist.com news service
Debora MacKenzie
BSE has been shown to spread naturally between sheep for the first time. It passed from mother to lamb, before or during birth, in an experimentally infected flock. But if the study shows the infection spreads more generally within the flock, that means BSE could still be lurking in Europe's sheep, possibly posing a greater health risk to people than that from "mad" cows.
Scientists found in 1996 that sheep develop a disease similar to BSE if they eat infected cattle tissue. But feeding cattle remains to sheep was banned in Britain in 1988, and in the EU in 1994. All the sheep infected before then should be gone by now.
So there should be no more BSE sheep – unless they can transmit BSE to each other. Cattle cannot do this, but sheep transmit a related disease called scrapie between themselves, apparently when they eat placentas and other birthing remains in the field. If BSE also spreads "horizontally" in this way – between other members of the flock – it might have kept spreading in sheep even after the feed ban.
And because the symptoms of BSE in sheep resemble scrapie, "mad" sheep might not have been noticed. Nearly 2700 sheep with apparent scrapie have now been tested for BSE in the UK. None so far had clear BSE, though two are being tested further. BSE-infected goats, which are biologically similar to sheep, were found in France and possibly the UK in 2005.
BSE-infected sheep are potentially more dangerous to human consumers than BSE-infected cows, as they carry the infection in more of the tissues people eat.
Mother to lamb
Sue Bellworthy and colleagues at the UK's Veterinary Laboratories Agency (VLA) report that two ewes experimentally infected with BSE in a flock in Warwickshire in 2000 gave birth to lambs in 2003 that died of BSE this year. This is the first confirmation of "vertical" transmission of BSE from mother to offspring. It has been suspected but never proved in cattle.
In sheep, given how scrapie spreads, "this was expected," Danny Matthews, a BSE expert at the VLA, told New Scientist. "But vertical transmission alone would not be enough to keep BSE going in the sheep population after the feed ban." Transmission would be limited to one family line, which would die out as animals die of BSE or are eaten.
The experimental herd is now being watched to see if adults can transmit BSE horizontally to other ewe's lambs now being born and raised within the flock. So far none has, and no uninfected adult sheep have caught the disease from experimentally infected sheep. But it's still "too early to say", cautions Matthews.
Journal reference: Veterinary Record (Aug 13, p 206)
BSE and vCJD - Learn more in our comprehensive special report.
http://www.newscientist.com/channel/health/bse/dn7861
British goat may have harboured BSE
18:34 08 February 2005
NewScientist.com news service
Debora MacKenzie
A British goat which died in 1990 may have had BSE, UK government officials revealed on Tuesday. The discovery means the infection may have circulated in goats in the past, and may even be circulating at low levels today.
This follows the recent disclosure of the first natural case of BSE to be found in a goat - a French animal that died in 2002. New Scientist has learned that the British goat was discovered as a result of the French case, as UK government scientists prepared for the increased testing of goats after the discovery.
It has long been assumed that sheep and goats may have been exposed to BSE in feed made from infected cattle. But unlike cattle, both creatures can transmit such infections between individuals, which might have kept the disease circulating after infected feed was banned.
BSE in sheep and goats would also be hard to spot, as both can naturally develop a similar disease called scrapie which has the same symptoms, although it is not thought to pose a risk to human consumers. And, unlike cattle, sheep experimentally infected with BSE carry the infectious prion in muscle meat, so the infection in sheep and goats could pose more of a risk to consumers.
For these reasons European Union countries have been testing sheep and goats for BSE since 2002. These tests discovered the infected French goat.
Telling the difference
"We were involved in helping evaluate the French data in December," says Danny Matthews of the UK's Veterinary Laboratories Agency, the EU reference lab for BSE. It was clear that the EU would probably ask for increased testing in goats as a result, he says.
In fact, from February, 80% of healthy slaughtered goats over the age of 18 months, plus "high risk" goats such as those found dead or unable to stand, should be tested, officials have just agreed. Three different test methods - called western blot, ELISA and immunohistochemistry (IHC) - will be used to distinguish scrapie from BSE.
"We haven't had to test many goats in the UK," says Matthews. "We thought we should test our current IHC on goat brain to make sure it distinguishes BSE." Besides goats and sheep experimentally infected with scrapie or BSE, they tested two brain samples at random from within a selection of goats thought to have died of scrapie.
One of them gave an IHC result that looked like BSE. "We can't do the other two tests as we processed all the tissue we had from that animal for IHC," says Matthews. But the team will nevertheless attempt to extract enough tissue from the IHC test material to do the definitive BSE test. This involves injecting tissue into mouse brain to see if BSE develops. But that will not yield results for two years.
"What is important now is not what happened back in 1990, but whether the infection is still circulating in goats," notes Matthews.
http://www.newscientist.com/channel/health/dn6987
Like lambs to the slaughter
* 31 March 2001
* Debora MacKenzie
* Magazine issue 2284
Suspect symptoms
What if you can catch old-fashioned CJD by eating meat from a sheep infected with scrapie?
Exclusive from New Scientist magazine
Four years ago, Terry Singeltary watched his mother die horribly from a degenerative brain disease. Doctors told him it was Alzheimer's, but Singeltary was suspicious. The diagnosis didn't fit her violent symptoms, and he demanded an autopsy. It showed she had died of sporadic Creutzfeldt-Jakob disease.
Photo: Murdo McLeod
Most doctors believe that sCJD is caused by a prion protein deforming by chance into a killer. But Singeltary thinks otherwise.
He is one of a number of campaigners who say that some sCJD, like the variant CJD related to BSE, is caused by eating meat from infected animals. Their suspicions have focused on sheep carrying scrapie, a BSE-like disease that is widespread in flocks across Europe and North America.
Now scientists in France have stumbled across new evidence that adds weight to the campaigners' fears. To their complete surprise, the researchers found that one strain of scrapie causes the same brain damage in mice as sCJD.
"This means we cannot rule out that at least some sCJD may be caused by some strains of scrapie," says team member Jean-Philippe Deslys of the French Atomic Energy Commission's medical research laboratory in Fontenay-aux-Roses, south-west of Paris.
Hans Kretschmar of the University of Göttingen, who coordinates CJD surveillance in Germany, is so concerned by the findings that he now wants to trawl back through past sCJD cases to see if any might have been caused by eating infected mutton or lamb.
Brain damage
Scrapie has been around for centuries and until now there has been no evidence that it poses a risk to human health. But if the French finding means that scrapie can cause sCJD in people, countries around the world may have overlooked a CJD crisis to rival that caused by BSE.
Deslys and colleagues were originally studying vCJD, not sCJD. They injected the brains of macaque monkeys with brain from BSE cattle, and from French and British vCJD patients. The brain damage and clinical symptoms in the monkeys were the same for all three. Mice injected with the original sets of brain tissue or with infected monkey brain also developed the same symptoms.
As a control experiment, the team also injected mice with brain tissue from people and animals with other prion diseases: a French case of sCJD; a French patient who caught sCJD from human-derived growth hormone; sheep with a French strain of scrapie; and mice carrying a prion derived from an American scrapie strain.
As expected, they all affected the brain in a different way from BSE and vCJD. But while the American strain of scrapie caused different damage from sCJD, the French strain produced exactly the same pathology.
Multiple strains
"The main evidence that scrapie does not affect humans has been epidemiology," says Moira Bruce of the neuropathogenesis unit of the Institute for Animal Health in Edinburgh, who was a member of the same team as Deslys.
"You see about the same incidence of the disease everywhere, whether or not there are many sheep, and in countries such as New Zealand with no scrapie," she says. In the only previous comparisons of sCJD and scrapie in mice, Bruce found they were dissimilar.
But there are more than 20 strains of scrapie, and six of sCJD. "You would not necessarily see a relationship between the two with epidemiology if only some strains affect only some people," says Deslys. Bruce is cautious about the mouse results, but agrees they require further investigation. Other trials of scrapie and sCJD in mice, she says, are in progress.
Deformed proteins
People can have three different genetic variations of the human prion protein, and each type of protein can fold up two different ways. Kretschmar has found that these six combinations correspond to six clinical types of sCJD: each type of normal prion produces a particular pathology when it spontaneously deforms to produce sCJD.
But if these proteins deform because of infection with a disease-causing prion, the relationship between pathology and prion type should be different, as it is in vCJD. "If we look at brain samples from sporadic CJD cases and find some that do not fit the pattern," says Kretschmar, "that could mean they were caused by infection."
There are 250 deaths per year from sCJD in the US, and a similar incidence elsewhere. Singeltary and other US activists think that some of these people died after eating contaminated meat or "nutritional" pills containing dried animal brain.
Governments will have a hard time facing activists like Singeltary if it turns out that some sCJD isn't as spontaneous as doctors have insisted.
Deslys's work on macaques also provides further proof that the human disease vCJD is caused by BSE. And the experiments showed that vCJD is much more virulent to primates than BSE, even when injected into the bloodstream rather than the brain. This, says Deslys, means that there is an even bigger risk than we thought that vCJD can be passed from one patient to another through contaminated blood transfusions and surgical instruments.
More at: Proceedings of the National Academy of Sciences (vol 98, p 4142)
http://www.pnas.org/cgi/content/full/041490898v1
Correspondence about this story should be directed to [email protected]
1900 GMT, 28 March 2001
* New Scientist
http://www.newscientist.com/channel/health/bse/mg16922840.300
12/10/76
AGRICULTURAL RESEARCH COUNCIL
REPORT OF THE ADVISORY COMMITTE ON SCRAPIE
Office Note
CHAIRMAN: PROFESSOR PETER WILDY
snip...
A The Present Position with respect to Scrapie
A] The Problem
Scrapie is a natural disease of sheep and goats. It is a slow
and inexorably progressive degenerative disorder of the nervous system
and it ia fatal. It is enzootic in the United Kingdom but not in all
countries.
The field problem has been reviewed by a MAFF working group
(ARC 35/77). It is difficult to assess the incidence in Britain for
a variety of reasons but the disease causes serious financial loss;
it is estimated that it cost Swaledale breeders alone $l.7 M during
the five years 1971-1975. A further inestimable loss arises from the
closure of certain export markets, in particular those of the United
States, to British sheep.
It is clear that scrapie in sheep is important commercially and
for that reason alone effective measures to control it should be
devised as quickly as possible.
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
http://www.bseinquiry.gov.uk/files/yb/1976/10/12004001.pdf
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.
PMID: 6997404
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6997404&dopt=Abstract
Adaptation of the bovine spongiform encephalopathy agent to primates
and comparison with Creutzfeldt- Jakob disease: Implications for
human health
THE findings from Corinne Ida Lasmézas*, [dagger] , Jean-Guy Fournier*,
Virginie Nouvel*,
Hermann Boe*, Domíníque Marcé*, François Lamoury*, Nicolas Kopp [Dagger
] , Jean-Jacques Hauw§, James Ironside¶, Moira Bruce [||] , Dominique
Dormont*, and Jean-Philippe Deslys* et al, that The agent responsible
for French iatrogenic growth hormone-linked CJD taken as a control is
very different from vCJD but is similar to that found in one case of
sporadic CJD and one sheep scrapie isolate;
http://www.pnas.org/cgi/content/full/041490898v1
0208h023: UK exports of sheep, goats and sheep/goat meats and meat products (1988 - 2001)
http://www.vegsource.com/articles/sheep_exports.htm
TSS
Link: 0208h023: UK exports of sheep, goats and sheep/goat meats and meat products (1988 - 2001)
#################### https://lists.aegee.org/bse-l.html ####################
Veterinary Services
Centers for Epidemiology and Animal Health March 2004
____________________________________________________________________________
_____________________________________________
Highlights of Phase II: Scrapie:
Ovine Slaughter Surveillance
Study 2002-2003
The purpose of the SOSS study was to estimate
the regional and national prevalence of scrapie in
mature cull sheep in the United States.
Phase I of SOSS was conducted from February
2001 through March 2002 and included refinement
of the study design and sample collection training.
The purpose of Phase I was to develop and modify
the sample collection and testing processes,
without emphasizing statistical results.
SOSS Phase II is similar to Phase I in that
sample collection procedures and testing were
used, along with a representative sample
allocation. Beginning April 1, 2002, and continuing
through March 31, 2003, Phase II included the
collection of tissue samples from 12,508 sheep
from 22 slaughter plants throughout the United
States (21 FSIS inspected, 1 State plant) and 1
large livestock market in Texas. The 21 FSIS plants
represented approximately two-thirds of the total
FSIS mature sheep slaughtered during the study
period. The livestock market represented
approximately one-half of the live sheep exported
to Mexico. All sample data were statistically
weighted to reflect the population from which the
sample was selected. The number of samples
collected from each plant on a specific day was
statistically weighted to represent the volume of
mature sheep slaughtered (sold) through each
plant (market) that specific day. This weight was
adjusted for the total volume of mature sheep
through the plant (market) from April 2002 through
March 2003. Within each facility sample collectors
were instructed to collect samples using systematic
sampling. Overall, the samples collected from the
22 plants and the livestock market represented
299,000 sheep (54 percent of the cull sheep
population, estimated at 550,000 head).
Sheep were traced to State of origin based on
ear tags and/or other information obtained by the
collector at the plant or market. For analysis
purposes, samples identified to individual States
were assigned to one of four defined regions.
Sometimes only a listing of multiple States could be
obtained for a group of sheep (e.g., market animals
accumulated across numerous States). These
samples were assigned to the Multiregion category
if the States they came from were not all in the
same region. In cases where a trace State was not
identified by the collector (n = 2,020), a region was
assigned based on their official identification
information. The 2001 NAHMS Sheep study
showed that at least 95 percent of cull sheep
movement was within the region of origin. Out of
the 12,508 samples submitted, all but 2,127 were
identified to a unique region (Table 1).
Table 1. Number of Samples Submitted, by Face Color
and By Region.
Samples Submitted
Region
Face
Color West Mountain Central East
Multiregion
Total
Black 100 535 680 1,023 453 2,791
White 493 2,997 1,993 1,283 1,472 8,238
Mottled 71 305 413 404 194 1,387
Unknown 6 32 4 42 8 92
Total 670 3,869 3,090 2,752 2,127 12,508
Obex, tonsil, and lymph-node tissues from each
sheep were tested using the immunohistochemistry
(IHC) technique at the National Veterinary Services
Laboratory. A positive case was defined as having
a positive test result on any tissue.
United States Department of Agriculture • Animal and Plant Health Inspection
Service • Safeguarding American Agriculture
Prior to the SOSS study, the estimated
pre as 0.07
p '96
spected
'96
hlights were excerpted from
Pha
revalence estimates
Of the 12,508 mature sheep sampled, valid (at
itive
0.20
s
.
Three tissue types (obex, tonsil, and
llected
in
s
valence of scrapie in the United States w
percent (based on unpublished data from the
NAHMS Sheep '96 study). However, the Shee
estimate was based on a mail-in survey of
producers who reported the presence of su
or confirmed cases of scrapie in their flock over a
period of 5 years, including lambs and mature
sheep. The flock estimate was then expanded
based on flock size to generate the animal-leve
prevalence estimate. The results of the SOSS
study cannot be directly compared to the Sheep
prevalence estimate because of differences in
study design, reference population, and data
collection methods.
The following hig
l
se II: Scrapie: Ovine Slaughter Surveillance
Study 2002-2003.
P
•
least one testable tissue) test results were
obtained from 12,491 (99.9 percent). A pos
result was recorded for any animal that tested
positive by IHC on one or more of the tissues
sampled. The overall weighted national
prevalence of scrapie in mature sheep is
percent. Estimates could not be made in the
West region due to the low number of sample
obtained. However, national estimates include
samples collected in the West region (Figure 1)
•
retropharyngeal lymph node) were co
from each sheep head for IHC testing. As
expected, each tissue type differed slightly
the number tested as well as the number of
positive results; however, the prevalence wa
similar for the three tissue types (Figure 2).
0.0
0.2
0.4
0.6
Figure 2. Percent of Sheep That Tested Positive for Scrapie,
by Tissue Type
Percent
Tissue Type
Obex Tonsil Retropharyngeal
lymph node
0.18 0.19 0.20
Scrapie prevalence (one or more tissue
lack-
ot
•
samples tested positive) was highest in b
faced sheep (0.84 percent). White-faced sheep
were far less likely to test positive for scrapie
(less than 0.01 percent). Some animals were
presented for sample collection with the skin
removed. Therefore, face color could not be
determined on these animals and they were n
included in these estimates (Figure 3).
West Mountain Central East
United States Department of Agriculture • Animal and Plant Health Inspection
Service • Safeguarding American Agriculture
0.0
0.2
0.4
0.6
0.8
1.0
Percent
Face Color
Figure 3. Percent of Sheep That Tested Positive for Scrapie,
by Face Color
0.00
0.84
0.12
White Black Mottled
p
t of
,
Age was determined based on the number of
•• visible permanent incisors. Four-year-old shee
tested positive (one or more tissue samples
tested positive) most frequently (0.49 percen
sheep tested). Scrapie prevalence increased
with age until the animals reached 4 years old
then decreased (Figure 4).
0.0
0.5
1.0
1.5
2.0
Black-faced sheep
National
Figure 4. Percent of Sheep That Tested Positive for Scrapie
(National and Black-faced Sheep), by Age
Percent
Age
0.11
0.00
0.21
0.54 0.49
1.77
0.13
0.69
1 and 2 years 3 years 4 years 5 years or more
enetics
ue samples from the 33 sheep that tested
pos
e at
______________________________
or more information, contact:
E7
G
Tiss
itive for scrapie were submitted for genetic
testing. All 33 samples were of the QQ genotyp
codon 171. This genotype has been characterized
as the least resistant to scrapie.
__
F
SDA:APHIS:VS:CEAH U
NRRC Building B, M.S. 2
2150 Centre Avenue
-8117 Fort Collins, CO 80526
970.494.7000
[email protected] E-mail: NAHMS
www.aphis.usda.gov/vs/ceah/cahm
N421.0304 #
____________________________________
) prohibits discrimination in
plaint of discrimination, write USDA, Director, Office of
yer.
ention of companies or commercial products does not imply
s nor
he U.S. Department of Agriculture (USDA T
all its programs and activities on the basis of race, color, national
origin, sex, religion, age, disability, political beliefs, sexual
orientation,
or marital status or family status. (Not all prohibited bases apply to all
programs.) Persons with disabilities who require alternative means for
communication of program information (Braille, large print, audiotape,
etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice
and TDD).
o file a com T
Civil Rights, Room 326-W, Whitten Building, 1400 Independence
Avenue, SW, Washington, DC 20250-9410 or call (202) 720-5964
(voice and TDD). USDA is an equal opportunity provider and emplo
M
recommendation or endorsement by the U.S. Department of
Agriculture over others not mentioned. USDA neither guarantee
warrants the standard of any product mentioned. Product names are
mentioned solely to report factually on available data and to provide
specific information.
United States Department of Agriculture • Animal and Plant Health Inspection
Service • Safeguarding American Agriculture
http://www.aphis.usda.gov/vs/ceah/ncahs/nahms/sheep/SOSS_highlights.pdf
Animal and
Plant Health
Inspection
SOSS
Phase II: Scrapie: Ovine Slaughter Surveillance
Study 2002-2003
snip...
Section I: Prevalence Estimates
A. Weighted Test
Results
1. Overall prevalence
Of the 12,508 mature sheep sampled, valid (at least one testable tissue)
test
results were obtained from 12,491 (99.9 percent). A positive result was
recorded for any animal that tested positive by immunohistochemistry (IHC)
on
one or more of the tissues sampled. The overall weighted national
prevalence of scrapie in mature sheep is 0.20 percent. Estimates could not
be
made in the West region due to the low number of samples obtained. However,
national estimates include samples collected in the West region.
a. Percentage of sheep that tested positive for scrapie, by region*:
Percent Sheep
Region
Mountain Central East Multiregion National
Pct.
Std.
Error Pct.
Std.
Error Pct.
Std.
Error Pct.
Std.
Error Pct.
Std.
Error
0.14 (0.06) 0.21 (0.10) 0.52 (0.15) 0.13 (0.07) 0.20 (0.04)
*Because of the low number of samples obtained in the West region, results
for the
West region are included in the National estimates but are not listed
individually.
snip...
http://www.aphis.usda.gov/vs/ceah/ncahs/nahms/sheep/SOSSphase2.pdf
TSS
----- Original Message -----
From: "Terry S. Singeltary Sr." <[email protected]>
To: <[email protected]>
Sent: Wednesday, August 24, 2005 9:11 PM
Subject: SCRAPIE USA UPDATE MARCH - JUNE 2005
##################### Bovine Spongiform Encephalopathy
#####################
From: TSS ()
Subject: SCRAPIE USA UPDATE MARCH - JUNE 2005
Date: August 24, 2005 at 7:03 pm PST
SCRAPIE USA MONTHLY REPORT 2005
AS of March 31, 2005, there were 70 scrapie infected source flocks (Figure
3). There were 11 new infected and source flocks reported in March (Figure
4) with a total of 51 flocks reported for FY 2005 (Figure 5). The total
infected and source flocks that have been released in FY 2005 are 39 (Figure
6), with 1 flock released in March. The ratio of infected and source flocks
released to newly infected and source flocks for FY 2005 = 0.76 : 1. IN
addition, as of March 31, 2005, 225 scrapie cases have been confirmed and
reported by the National Veterinary Services Laboratories (NVSL), of which
53 were RSSS cases (Figure 7). This includes 57 newly confirmed cases in
March 2005 (Figure 8). Fourteen cases of scrapie in goats have been reported
since 1990 (Figure 9). The last goat cases was reported in January 2005. New
infected flocks, source flocks, and flocks released or put on clean-up plans
for FY 2005 are depicted in Figure 10. ...
FULL TEXT ;
http://www.aphis.usda.gov/vs/nahps/scrapie/monthly_report/monthly-report.htm
l
SCRAPIE USA JUNE 2005 UPDATE
AS of June 30, 2005, there were 114 scrapie infected and source flocks
(Figure 3). There were 14 new infected and source flocks reported in June
(Figure 4) with a total of 123 flocks reported for FY 2005 (Figure 5).
snip...
In addition, as of June 30, 2005, 448 scrapie cases have been confirmed and
reported by the National Veterinary Services Laboratories (NVSL), of which
106 were RSSS cases (Figure 7). This includes 81 newly confirmed cases in
June 2005 (Figure 8). Fifteen cases of scrapie in goats have been reported
since 1990 (Figure 9). The last goat case was reported in May 2005.
snip...end
http://www.aphis.usda.gov/vs/nahps/scrapie/monthly_report/monthly-report.htm
l
USDA/APHIS
SOSS
Phase II: Scrapie: Ovine Slaughter Surveillance
Study 2002-2003
http://www.aphis.usda.gov/vs/ceah/ncahs/nahms/sheep/SOSSphase2.pdf
