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Our Perspective
A Look At How NCBA Border Directive Might Fare
The directive that sailed through the cattle industry convention last week and will be sent to the entire National Cattlemens' Beef Association membership on Feb. 17 set forth a laundry list of concerns NCBA wants addressed before it can support a border reopening. The directive's 11 key points include:
Prohibit the importation of cattle and beef products from cattle more than 30 months of age.
Assure all Canadian firewalls to prevent BSE, specifically adherence to their feed ban, are functioning properly.
No feeder cattle imported animal health standards, especially bluetongue and anaplasmosis, are harmonized.
Movement of Canadian cattle into the U.S. must be managed to minimize market disruptions.
Fed cattle imported for immediate slaughter must be certified to be less than 30 months of age at time of importation.
Ban the use of fetal bovine serum from heifers imported for immediate slaughter.
Disallow USDA grades and stamps on any imported beef.
Feeder cattle must be branded with "CAN," individually ID'd with an ear tag, certified to be less than 30 months of age at time of slaughter, shipped in sealed trucks from the border directly to an approved feedlot, then moved directly in sealed trucks to slaughter.
Canadian feeder heifers imported to the U.S. must be spayed.
USDA must work with primary trade partners to ensure expanded access for U.S. beef exports isn't jeopardized in any way by expanded importation of Canadian cattle and beef.
The administration must reach an agreement to re-establish beef and beef byproduct trade with Japan, South Korea and Mexico, and apply economic sanctions if necessary.
USDA has already taken action on Point 1. Point 2 was partially addressed by NCBA's trade delegation, and additional investigations are ongoing with reports expected prior to March 7.

Point 3 isn't only obvious, but doable with little difficulty. The reality is Canada has far more at stake than the U.S., and this non-tariff trade barrier issue has existed for nearly 20 years. It must be resolved and aligned with the science immediately, as the U.S. will never have this much leverage again.

Point 4 is merely a restatement of past NCBA policy but it points out just how complicated implementing this ruling will be and the possible need for more time. It's also an issue difficult to define and adhere to without trade first being established. Nothing in the current rule addresses mitigating negative short-term market effects.

Point 5 is essentially already part of the USDA rule and isn't expected to be a major stumbling block. Point 6 is another difficult-to-resolve issue, while Point 7 is merely a restatement of current NCBA policy that USDA will likely continue to ignore. Point 8 is essentially a part of the current rule.

Point 9 is a major departure from the current rule and would be easy to implement. But, it's not likely to happen as the provisions and tracking of these heifer feeders are considered to be adequate. While inherently obvious, Point 10 isn't expected to carry much weight.

Point 11, however, is critical and the most controversial. USDA seems adamantly opposed to it, feeling the border reopening will lead to reopening of U.S. export markets. This will likely be the most difficult objective to achieve.
-- Troy Marshall
 
NCBA IS TRYING TO gain some brownie points and hold on to some members. This is something R-cult may have come up with. As I recall the border is open to 39 states for exporting feeder cattle to canada. Its nto really logical to think someone is going ot ship cattle up here from far deep in the south is it?
 
Manitoba_Rancher said:
NCBA IS TRYING TO gain some brownie points and hold on to some members. This is something R-cult may have come up with. As I recall the border is open to 39 states for exporting feeder cattle to canada. Its nto really logical to think someone is going ot ship cattle up here from far deep in the south is it?

--------------------------------------------------------------------------------
Canada lifts cattle import restrictions
this document web posted: Thursday March 18, 2004 20040318p10

By Barry Wilson
Ottawa bureau

After more than a decade of pressure from Canadian and American cattle producers, the federal government has agreed to open the border year-round to feeder cattle imports from most areas of the United States.

Effective April 1, feeders from 39 low-and-medium-risk states for bluetongue can be shipped north year-round. Now, they are restricted to seasonal imports.

Cattle from high-risk bluetongue states, including many southern states, can be shipped north if they are tested and found free of the disease or spend 60 days in a low-or-medium-risk state in transit.

In Canada, they must be confined to feedlots and not enter the national herd. There will be no restrictions based on fear of anaplasmosis.

Until last week, the Canadian Food Inspection Agency had restricted imports because of fear the diseases could be shipped north. The cattle industry on both sides of the border had insisted the disease risk did not justify the border restriction.

The diseases affect livestock but not humans.

"We have reviewed the science on this," CFIA president Richard Fadden told the Senate agriculture committee March 11. "In respect of anaplasmosis, we decided there are enough controls that can be imposed in-country to prevent the spread of the disease. Basically, we are saying that in respect of anaplasmosis, we are deregulating."

The Canadian cattle industry said it's about time. It has tied Canada's restrictions on feeders moving north to U.S foot-dragging on opening the border to Canadian cattle moving south.

"Our expectation is that with this irritant set aside, our cause of getting cattle across the border will receive more favourable consideration on the U.S. side," said Rob McNabb of the Canadian Cattlemen's Association.

American cattle producers did not make that promise but they praised the decision.

"This is a significant development," Kansas cattle producer and National Cattlemen's Beef Association president Jan Lyons said in a statement issued in Washington, D.C. The American cattle lobby said it is committed to science-based border rules.

"Our ability to work with Canada to harmonize our regulations based upon scientific facts and a commitment to fair trade gives us renewed hope that we can also harmonize international regulations relating to BSE," said NCBA chief executive officer Terry Stokes.

Fadden said the decision to open the border is not risk-free, but it is manageable.

"The bottom line is, there remains a risk," he told senators. "If we change the rules as the minister has effective April 1, there is a risk that bluetongue will be transmitted to the national herd. We will have to deal with that. There is also a risk it could be transmitted to wildlife."



MB rancher note this part.....of the preceding

Cattle from high-risk bluetongue states, including many southern states, can be shipped north if they are tested and found free of the disease or spend 60 days in a low-or-medium-risk state in transit.
 
One more MB rancher..

Canada proposes new science-based import regulations to allow expanded access for U.S. cattle and beef products
Jan. 31/05
From a press release
OTTAWA -- The Canadian Food Inspection Agency (CFIA) today announced proposed regulations to remove import restrictions
from a range of currently prohibited U.S. commodities. These restrictions
were introduced following the detection of bovine spongiform encephalopathy
(BSE) in Washington State on December 23, 2003.
Based on the guidelines of the World Organization for Animal Health, the
CFIA plans to permit the importation of live cattle born in 1998 or later,
beef from animals of any age from which specified risk material has been
removed and various other commodities. Products that may pose a higher risk,
such as certain animal feeds, will remain prohibited.
The proposed regulations will further align Canada's BSE-specific policy
for imports from the United States with science-based international
guidelines for safe trade, which are designed to protect public and animal
health.
With respect to bluetongue and anaplasmosis, the proposed regulations
will allow for year-round access for U.S. feeder cattle destined for
slaughter into Canadian feedlots, while maintaining the highest level of
animal health protection. Additionally, work to expand the scope for further
change relative to breeding cattle will follow the publication this year of a
recently completed study conducted in Alberta.
"Our response to BSE continues to be based on science, and science
clearly demonstrates that safe trade can and should continue with appropriate
safeguards in place," said Agriculture and Agri-Food Minister Andy Mitchell.
"The consistent public and animal health measures that the United States and
Canada have adopted will allow us to move toward the full reintegration of
our markets."
The proposed regulations have been published in Canada Gazette I. A
30-day comment period ending on March 1, 2005 is being provided to allow
interested parties the opportunity to provide comments. In the interim,
current import restrictions will remain in effect.
The CFIA is currently developing a broader BSE-related import policy
that will apply to any country that has reported the disease. As with the
currently proposed regulations, this new policy will reflect the Government's
ongoing commitment to follow recognized science and the most current
understanding of BSE. The CFIA is confident that moving Canada's import
policy toward international guidelines will encourage other countries to
adopt similar, more appropriate approaches
 
thanks for the info Frenchie:

I thought they had lifted those restrictions but wasnt sure. See how some of these people get things screwed up.
 
What bothers me about the Anaplas and Blue restrictions, is Canada is to drop them but their are still States that won't allow imports of cattle from other states without the test. I looked it up I can't find the list right now but I know that Montana and Wyoming were two of the States that other states won't accept cattle from without the test. There were about 14 states that are restricted and not all of them were from the far south as you would think.
 
Tam said:
I looked it up I can't find the list right now but I know that Montana and Wyoming were two of the States that other states won't accept cattle from without the test.

Tam, those states must not take many cattle- I've seen 100's of thousands of cows and calves shipped out of this state without any being tested- only on a vets health certificate.....Some of the University studies I've seen consider the northern tier states free of Anaplas and Bluetongue-- I think it was MSU that did a several year study, testing cattle in various herds around the state, to prove to the Canadians that we were free....... Just a trade barrier-- and now when you get a REAL disease that threatens not only herd health but could pose a threat to human health, along with the viability of our US cattle industry, you complain about us wanting some assurances...... Sorry I can't give you any sympathy.......
 
Just a trade barrier-- and now when you get a REAL disease that threatens not only herd health but could pose a threat to human health, along with the viability of our US cattle industry, you complain about us wanting some assurances......

Time to come to your senses and realize that BSE is not as big of a problem as you and your fellow R-Calfers have tried to make it out to be. #1 it is not contagious like anaplas or bluetongue and is no risk what so ever to herd health and #2 it POSSIBLY represents a minute risk to human health. There are far more people contract e-coli or die from other food risks in a month than will die in a century from vCJD. Yes it's just a trade barrier. Keep crying wolf and you'll get eaten up.
 
By Oldtimer: Tam, those states must not take many cattle- I've seen 100's of thousands of cows and calves shipped out of this state without any being tested- only on a vets health certificate.....Some of the University studies I've seen consider the northern tier states free of Anaplas and Bluetongue-- I think it was MSU that did a several year study, testing cattle in various herds around the state, to prove to the Canadians that we were free....... Just a trade barrier-- and now when you get a REAL disease that threatens not only herd health but could pose a threat to human health, along with the viability of our US cattle industry, you complain about us wanting some assurances...... Sorry I can't give you any sympathy.......


The University, National and International studies I have seen consider the BSE testing, surveilence, regulations and compliance levels implemented by Canada (on par and some above the US) as acceptable measures for control and irradication. You wanted assurances, Canada gave them to you.

Trade barrier - funny you should mention that!!
 
Bill said:
Time to come to your senses and realize that BSE is not as big of a problem as you and your fellow R-Calfers have tried to make it out to be. #1 it is not contagious like anaplas or bluetongue and is no risk what so ever to herd health and #2 it POSSIBLY represents a minute risk to human health.

Bill- which of the 100 theories about origin, contraction, and spread do you buy into? Every time it starts looking close to having a "sound science" answer- some scientist makes a new discovery and 5 more theories show up.... Even the CFIA vets have several theories of transmission- cow to cow, cow to calf, feed-- which theory is right? Then you add in orgonosphates, minerals, and a spotaneous occurence as possible causes--Now scientists are showing that it may be possible to transmit from animal to animal in other animals- goats and sheep......Scientists are finding prions in nerves in muscle meats and viscera--Cattle under thirty months are supposed to be immune- but then they find several around the world just over 20 months old that are infected....Too many grey areas...

Canada needs to test everything until they find out the extent of their problems and we need to keep up the barriers until we know the extent of the infection and more is known about the disease.........
 
Oldtimer this won't happen as long as big money is involved.


ps If Wal-Mart is lowering prices every day, how come nothing is free yet? :cry:
 
Oldtimer there isn't a bubble big enough to protect us from all the "theories" out there! From the mattress you sleep on to the eulogy at your passing. Those suspenders you wear - there's a theory that they aggravate neck, shoulder and back problems (related to the force put upon) and not to mention the "snap" effect!
All the theories in the world won't protect you - every second a factor changes, for the good and for the bad. How do we make it to the end of the day? We apply human reasoning to the circumstance, we use what we know at any given time. I don't want to stick my head in the sand but I also don't want to live my life trying to outrun the what if's - it's humanly impossible and somebody somewhere would have a theory as to why the "bubble' is not good for you either.
 
Oldtimer said:
Bill said:
Time to come to your senses and realize that BSE is not as big of a problem as you and your fellow R-Calfers have tried to make it out to be. #1 it is not contagious like anaplas or bluetongue and is no risk what so ever to herd health and #2 it POSSIBLY represents a minute risk to human health.

Bill- which of the 100 theories about origin, contraction, and spread do you buy into? Every time it starts looking close to having a "sound science" answer- some scientist makes a new discovery and 5 more theories show up.... Even the CFIA vets have several theories of transmission- cow to cow, cow to calf, feed-- which theory is right? Then you add in orgonosphates, minerals, and a spotaneous occurence as possible causes--Now scientists are showing that it may be possible to transmit from animal to animal in other animals- goats and sheep......Scientists are finding prions in nerves in muscle meats and viscera--Cattle under thirty months are supposed to be immune- but then they find several around the world just over 20 months old that are infected....Too many grey areas...

Canada needs to test everything until they find out the extent of their problems and we need to keep up the barriers until we know the extent of the infection and more is known about the disease.........

What CFIA vets have said anything about cow to cow transmission or cow to calf?? If you have such proof bring it forward.

"but then they find several around the world just over 20 months old that are infected"

Is this more fearmongering taken out of some R-Calf release? I don't know what's worse, the profanity some seemed so bothered by on the old site or the outright lies which are posted by others with absolutely nothing to back it up.
 
Bill said:
Oldtimer said:
Bill said:
Time to come to your senses and realize that BSE is not as big of a problem as you and your fellow R-Calfers have tried to make it out to be. #1 it is not contagious like anaplas or bluetongue and is no risk what so ever to herd health and #2 it POSSIBLY represents a minute risk to human health.

Bill- which of the 100 theories about origin, contraction, and spread do you buy into? Every time it starts looking close to having a "sound science" answer- some scientist makes a new discovery and 5 more theories show up.... Even the CFIA vets have several theories of transmission- cow to cow, cow to calf, feed-- which theory is right? Then you add in orgonosphates, minerals, and a spotaneous occurence as possible causes--Now scientists are showing that it may be possible to transmit from animal to animal in other animals- goats and sheep......Scientists are finding prions in nerves in muscle meats and viscera--Cattle under thirty months are supposed to be immune- but then they find several around the world just over 20 months old that are infected....Too many grey areas...

Canada needs to test everything until they find out the extent of their problems and we need to keep up the barriers until we know the extent of the infection and more is known about the disease.........

What CFIA vets have said anything about cow to cow transmission or cow to calf?? If you have such proof bring it forward.

"but then they find several around the world just over 20 months old that are infected"

Is this more fearmongering taken out of some R-Calf release? I don't know what's worse, the profanity some seemed so bothered by on the old site or the outright lies which are posted by others with absolutely nothing to back it up.

Bill- Where you been? Both were posted on this site- the one quoting the CFIA vet (and they named him) was an article from a CFIA news release shortly after the 4th Alberta cow was found- he said they were looking at animal to animal transmission and the possibility that the cow had been infected by its mother- also looking at herdmates ( I remember it clearly because I had never before heard of this theory and posted it asking questions)- Found out later that this is a more widespread theory than I knew.....The 20 month link was just on here a few weeks ago- showed the number of under 30 month cattle by age and country that had tested positive for BSE-- I'm not sure of the actual number when you added them up- somewhere around 30-40.....
If we get our archives back, I'll see if I can find them for you because Canadians have a big reason to learn all they can about this disease.......
 
Oldtimer said:
Bill said:
Oldtimer said:
Bill- which of the 100 theories about origin, contraction, and spread do you buy into? Every time it starts looking close to having a "sound science" answer- some scientist makes a new discovery and 5 more theories show up.... Even the CFIA vets have several theories of transmission- cow to cow, cow to calf, feed-- which theory is right? Then you add in orgonosphates, minerals, and a spotaneous occurence as possible causes--Now scientists are showing that it may be possible to transmit from animal to animal in other animals- goats and sheep......Scientists are finding prions in nerves in muscle meats and viscera--Cattle under thirty months are supposed to be immune- but then they find several around the world just over 20 months old that are infected....Too many grey areas...

Canada needs to test everything until they find out the extent of their problems and we need to keep up the barriers until we know the extent of the infection and more is known about the disease.........

What CFIA vets have said anything about cow to cow transmission or cow to calf?? If you have such proof bring it forward.

"but then they find several around the world just over 20 months old that are infected"

Is this more fearmongering taken out of some R-Calf release? I don't know what's worse, the profanity some seemed so bothered by on the old site or the outright lies which are posted by others with absolutely nothing to back it up.

Bill- Where you been? Both were posted on this site- the one quoting the CFIA vet (and they named him) was an article from a CFIA news release shortly after the 4th Alberta cow was found- he said they were looking at animal to animal transmission and the possibility that the cow had been infected by its mother- also looking at herdmates ( I remember it clearly because I had never before heard of this theory and posted it asking questions)- Found out later that this is a more widespread theory than I knew.....The 20 month link was just on here a few weeks ago- showed the number of under 30 month cattle by age and country that had tested positive for BSE-- I'm not sure of the actual number when you added them up- somewhere around 30-40.....
If we get our archives back, I'll see if I can find them for you because Canadians have a big reason to learn all they can about this disease.......

I look forward to seeing those "facts" though it is funny all you have for proof is what you read on this site. Yes Canadians and especially American producers need to learn all they can about BSE from credible sources. There is so much BS and misinformation floating around the US about BSE it is incredible. The possibility of cow to cow or cow to calf transmission has not been mentioned in any news in Canada and it would be on all the news sources if CFIA was discussing it.
 
the bse age report was part of an oie report that was linked to ncba's border regulations. you might be able to find it on ncba's website.
 
I look forward to seeing those "facts" though it is funny all you have for proof is what you read on this site. Yes Canadians and especially American producers need to learn all they can about BSE from credible sources. There is so much BS and misinformation floating around the US about BSE it is incredible. The possibility of cow to cow or cow to calf transmission has not been mentioned in any news in Canada and it would be on all the news sources if CFIA was discussing it.[/quote]

All you have to do is have some Canadians that read it before step up on say it was posted. I posted it, but have no way of getting the archives back. Will see if I can find it on a search.
 
If can understand English maybe we could get somewhere. The link was posted from a Canadian paper stating what the cfia vet said. It wasn't something we just made up and posted to serve as facts. :mad:
 
Oldtimer said:
Tam said:
I looked it up I can't find the list right now but I know that Montana and Wyoming were two of the States that other states won't accept cattle from without the test.

Tam, those states must not take many cattle- I've seen 100's of thousands of cows and calves shipped out of this state without any being tested- only on a vets health certificate.....Some of the University studies I've seen consider the northern tier states free of Anaplas and Bluetongue-- I think it was MSU that did a several year study, testing cattle in various herds around the state, to prove to the Canadians that we were free....... Just a trade barrier-- and now when you get a REAL disease that threatens not only herd health but could pose a threat to human health, along with the viability of our US cattle industry, you complain about us wanting some assurances...... Sorry I can't give you any sympathy.......


you neglected to mentioned that 200,000 calves left Montana each yr in the non- insect season. to Alberta feedlots. trade barriar my ass
Bluetongue Virus
I. Background on Bluetongue

Bluetongue disease (BLU) is an OIE List A disease that causes substantial economic losses due to its effect on animals, e.g. sheep, and impacts cattle industries due to international regulations restricting movement of livestock and livestock germplasm from the U.S. BLU-endemic areas to BLU-free areas such as the European Union. U.S. losses due to BLU have been ca. $120 million annually, and world-wide losses are estimated at $3 billion annually (Walton and Osburn 1992). This is a prominent non-tariff trade barrier throughout the world.

Bluetongue disease was first reported in South African sheep (Hutcheon 1902). BLU virus was isolated from sheep in California in 1952 (McKercher et al. 1953). Thereafter, the biting midge Culicoides sonorensis was identified as a U.S. vector (Price and Hardy 1954). The BLU viruses may infect several domestic and wild ruminant species. Clinical signs in sheep and cattle are described elsewhere (Parsonon 1992, MacLachlan et al. 1992). The disease in sheep is characterized by inflammation and congestion leading to hemorrhages, cyanosis and ulceration of the mucous membranes. There may be laminitis, myositis and edema of the head and neck. Fetal abnormalities may occur when animals are infected early in pregnancy. The severity of the disease may vary, with a mortality rate in sheep between 5-50 percent. Clinical BLU disease in cattle is rare (<5% of infected animals): the virus has little if any effect on reproduction, but cattle may show a prolonged viremia. Prenatal infection early in utero may lead to embryonic death. Fetuses infected at later stages of gestation survive but are not persistently infected, and infected animals develop antibodies. (Parsonson 1992). The disease may range from sub-clinical infection (North American elk) to an acute hemorrhagic disease with high mortality (white-tailed deer).

Bluetongue viruses are double-stranded RNA viruses (genus Orbivirus, family Reoviridae). The BLU genome consists of 10 genes which encode mRNAs for seven structural and three nonstructural proteins. The RNA genome is encapsidated in a double-layered protein coat (Roy et al. 1990). The outer coat contains two major proteins, VP2 and VP5. There are 24 serotypes of BLU virus throughout the world, with serotype specificity residing in VP2 (Mecham et al. 1996). The inner coat is composed of two proteins, VP3 and VP7. VP7 contains group-specific epitopes and has been shown to be the virus attachment protein (Xu et al. 1997). When VP2 is cleaved from the outer capsid an infectious subparticle is produced. An inner core particle results from further enzyme treatment (Mertens et al. 1987).

There are genetic similarities among BLU serotypes and related orbiviruses, e.g. African horse sickness and epizootic hemorrhagic disease (EHD) viruses (Gould et al. 1992). Nucleotide sequences for BLU and EHD genes show close relationships between BLU and EHD viruses from the same geographic region (Pritchard et al. 1995, Cheney et al. 1996). The relationships between viral diversity and the different Culicoides vectors present in different regions are unknown. Culicoides vectors influence BLU virus biology (Tabachnick et al. 1992) and modern tests have been applied to Culicoides vectors to provide an ecological perspective (Nunamaker et al. 1997).

Bluetongue viruses are distributed worldwide, wherever there are Culicoides vectors (St. George and Kegao 1996). There are regional differences in the viruses, species of Culicoides vectors and clinical signs in animals, i.e. clinical BLU disease is generally not seen in the Central American-Caribbean Basin where the vector is C. insignis. The potential for BLU in Europe has resulted in animal health requirements to ensure BLU-free animal imports. C. obsoletus and C. pulicaris, BLU capable vectors in the laboratory (Jennings and Mellor 1987), are very common in northern Europe (Mellor 1993). Since there are no data on mechanisms controlling vector ability, BLU incursions remain a concern.

II. Epidemiology of BLU

United States BLU serotypes are 2, 10, 11, 13 and 17 (Barber 1979, Gibbs and Greiner 1988). A survey for BLU antibody in U.S. cattle ranged from 0-79% in different states (Metcalf et al. 1981). The lowest prevalence was in northern states (6) and was confirmed during the next two decades (Pearson et al. 1992). A large portion of the U.S. is considered endemic for BLU viruses.

Bluetongue 11 occurred in Canada only in the Okanagan Valley, British Columbia in 1976 and 1987 (Dulac et al. 1989, Dulac et al. 1992, Sterritt and Dulac 1993). The mechanisms responsible for BLU epidemiology are unknown, although the presence of these viruses is dependant on the presence of suitable Culiciodes populations.

The principle BLU vector in North America is considered to be the subspecies C. sonorensis (Tabachnick 1996). The northeastern U.S. is generally considered to be BLU free based on the absence of C. sonorensis, failure to isolate BLU antibodies from animals and the consistent low prevalence of BLU antibody in cattle (Tabachnick and Holbrook 1992). Regions of the U.S. have been declared BLU free based on results of the lab's studies (Walton et al. 1992, Tabachnick and Holbrook 1992, Tabachnick 1996).

Other regions in the world maintain different BLU serotypes and different Culicoides vectors. Australia has BLU serotypes 1, 3, 9, 15, 16, 20, 21 and 23 vectored by C. wadai, C. brevitarsis, C. fulvus and C. actoni. Bluetongue serotypes are found in Asia and the Middle East. Africa has serotypes 1-19, 22 and 24 vectored by C. imicola. The Central American-Caribbean Basin has BLU serotypes 1, 3, 4, 6, 8, 12 and 17.

III. Partnerships Addressing BLU Disease Issues in the U.S.

Due to the serious effect of BLU disease on U.S. livestock and livestock trade, several groups are involved in BLU disease research to characterize BLU epidemiology, define disease-free regions and develop strategies to reduce the impact of domestic BLU viruses on U.S. exports while protecting the U.S. from incursions of exotic BLU viruses. Knowledge of factors controlling BLU pathogenesis in cattle is essential to assess the risk of an exotic BLU being pathogenic in U.S. cattle. This would pose a substantial risk to large areas of the U.S. where 30-50% of cattle may be seropositive for BLU.

Surveillance for BLU in the U.S. is conducted annually using a serosurvey of cattle bloods by the USDA, APHIS National Veterinary Services Laboratories. The USDA, Agricultural Research Service, Arthropod-borne Animal Diseases Research Laboratory conducts research to develop information on BLU viruses, interactions with Culicoides vectors and pathogenesis in animal hosts designed to develop novel control strategies and provide risk assessment to protect the U.S. from emerging BLU serotypes. University collaborators in California and Florida provide information on BLU epidemiology, vector ecology and host-virus interactions. Biochemical markers for BLU virulence are being developed in cooperation with university cooperators in Wisconsin. The ABADRL has provided numerous diagnostic strategies for BLU and EHD viruses (Mecham and Wilson, 1994). In situ hybridization tests for BLU and EHD viral nucleic acids are being developed by university cooperators in Georgia.

IV. Key Points Concerning Bluetongue Disease

Bluetongue is a List A disease with serious consequences for sheep and other livestock. Introduction into BLU-free regions or countries such as those in the European Union is considered dangerous and has resulted in non-tariff trade barriers and specific phytosanitary regulations. Importation of exotic BLU viruses into new ecosystems risks changes in the pathogenesis of these viruses.
Bluetongue is considered endemic in the U.S. although 17 states in the north-northeastern region (ME, NH, VT, RI, MA, CT, NY, PA, NJ, DE, MD, WV, IN, OH, MI, WI, IL) may be considered BLU free due to the absence of a suitable vector. Transmission of BLU is totally dependant on the presence of a suitable vector, which is Culicoides sonorensis in the U.S.
Livestock may be moved from regions of the U.S. if tested to be BLU seronegative using internationally accepted tests (immunodiffusion, linked immunosorbant assay). Animals may be moved without testing to Canada during the vector-free season from the BLU-free north-northeastern U.S.
Only BLU 2, 10, 11, 13 and 17 have been found in the U.S. The risk of exotic BLU serotypes in U.S. vectors leading to changes in BLU pathogenesis in U.S. livestock is unknown.
BLU viruses may be isolated using several methods, e.g. intravenous innoculation of embryonating chicken eggs, susceptible sheep or directly in cell culture. BLU viruses may be detected using molecular methods such as Polymerase Chain Reaction (PCR) with high sensitivity. Remnants of BLU virus nucleic acid have been detected in cattle with no evidence of infectious virions.
Serological tests include group and serotype specific tests, e.g. immunodiffusion, complement fixation and Enzyme-Linked Immunosorbant Assays (ELISAs).
Live attenuated BLU virus vaccines are available for different serotypes. Vaccines should only be used in sheep, and should not be used during the first half of pregnancy. Although multivalent vaccines are available these are not recommended due to the potential for recombination and reassortment between serotypes. Live attenuated vaccines also pose the risk of reversion to virulence in the vector.
The severe restrictions on the movement of livestock due to BLU virus are based on fear that carrier cattle lacking BLU virus antibody provide a source of infection, and the fear that entry of exotic serotypes could pose great risk in new environments. Evidence is available that seronegative BLU carrier cattle are unlikely to exist and such animals are not a factor in BLU epidemiology. The danger of exotic BLU serotypes is unknown.
V. References

Barber TL. 1979. Temporal appearance, geographic distribution and species of origin of bluetongue virus serotypes in the United States. Am. J. Vet. Res. 40:1654-1656

Cheney IW, Yamakawa M, Roy P, Mecham JO, Wilson WC. 1996. Molecular characterization of the segment 2 gene of epizootic hemorrhagic disease serotype 2: Gene sequence and genetic diversity. Virology 224:555-560.

Dulac GC, Duboc C, Meyers DJ, Taylor EA, Ward D, Sterritt WG. 1989. Incursion of bluetongue virus type 11 and epizootic hemorrhagic disease of deer type 2 for two consecutive years in the Okanagen Valley. Can. Vet. J. 30:351-354.

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