Canadian Food Inspection Agency Canada
Français Contact Us Help Search Canada Site
Home What's New Acts and Regulations Site Map
Food Safety Animal Health Plant Protection Corporate Affairs

bullet Main Page - Animal Products
bullet Main Page - Animal Health
bullet Act and Regulations
bullet Animal Welfare / Transportation of Animals
bullet Canadian Animal Health Consultative Committee (CAHCC)
bullet Disease Control
bullet Disease Surveillance
bullet Export
bullet Hatchery Program
bullet Import
bullet Offices

Animals > Manuals > Accredited Veterinarian Manual  

7 Scrapie Flock Certification Program

Printer friendly PDF version

This section provides information on the duties of the accredited veterinarian in the delivery of the Scrapie Flock Certification Program (SFCP).

7.1 The Disease
Etiology 1. While the precise cause of the disease is still a subject of significant research, abnormal prion protein is associated with the presence of disease.
Susceptible Species 2. Scrapie is a naturally occurring disease of domestic and wild (mouflon) sheep and goats.
Distribution 3. The disease was first reported in sheep over 250 years ago and in Canada in 1938. Scrapie is currently recognized in many sheep raising countries. New Zealand and Australia are notable as countries recognized free from the disease.
Epidemiology 4. Pregnancy appears to trigger the migration of abnormal prion protein to the reproductive tract. Birthing fluids and tissues, such as placenta, from infected females contain large quantities of the scrapie agent. Healthy animals become infected by eating or licking contaminated materials in the lambing or kidding environment. Newborn lambs and kids sharing the same contaminated environment (lambing pen) are extremely susceptible to infection. Adult females sharing the same environment are also at risk. Although scrapie is an infectious disease, it is not highly contagious. In contrast to some diseases such as foot and mouth, casual contact between animals and inanimate objects, such as vehicle tires, people or the wind, are not known to transmit scrapie.

Abnormal prion proteins are extremely resilient to traditional approaches to disinfection, being very resistant to both chemical and physical inactivation and stable over a wide pH and temperature range. While they undergo a significant decrease in infectivity titre with time, they have been demonstrated to persist in the environment for periods of years. Reports from Iceland have suggested that environmental contamination or hay mites acting as mechanical vectors have resulted in the reintroduction of scrapie. This phenomenon has not been an epidemiological observation in North America.

Several separate research studies on the potential of scrapie transmission by embryos have produced conflicting results. At present, there is inadequate information, other than pertaining to genetics, to negate embryo transfer or to provide advice on appropriate measures to mitigate the risk of scrapie transmission from an embryo of unknown genotype. There is no evidence to date that implicates semen in the transmission of scrapie.
Genetic Effects Genetic makeup has been determined to be a significant factor in a sheep’s susceptibility to infection with scrapie. At this time, a correlation between specific genetics and related scrapie susceptibility has not been determined for goats. Current experimental evidence indicates that there are different forms of the sheep prion proteins. Some forms are highly susceptible to the structural transformation to the abnormal form found in scrapie, while others are resistant to this change. As in all mammals, sheep are diploid organisms, so that all cells contain two copies of each chromosome and thus two copies of the gene that codes for the prion protein. Genes are made up of codons. A codon is a stretch of DNA that determines which particular amino acid will be included at a particular location of a protein (in this case the prion protein). The prion protein is composed of 256 amino acids; therefore there are 256 codons determining these amino acids. In the literature concerning susceptibility to various strains of scrapie, three codons are discussed: 171, 154 and 136. In North America, two of these codons are given primary importance: 171 and 136. The presence of an arginine ®) at codon 171 of the prion protein confers resistance to the prion protein undergoing the structural change associated with scrapie in North America. The presence of glutamine (Q) or histidine (H - treated the same as a Q) at codon 171 results in the prion protein being susceptible to the structural change associated with North American scrapie. An alanine (A) at codon 136 confers resistance to the prion protein undergoing the structural change associated with North American scrapie. The presence of valine (V) at codon 136 can produce susceptibility to structural change associated with North American scrapie. V at site 136 is linked with Q at site 171 such that R cannot be found at site 171 in combination with V at site 136.

Scrapie susceptibility as defined by the codons 171 and 136 are as follows:

Most susceptible 171QQ > 136AV171QR > 136AA171QR > 171RR Greatest resistance

It is still not known whether animals with these latter genotypes do not become infected with the scrapie agent or whether they are merely protected from developing the clinical signs of scrapie.

The specific amino acids and the sites that appear to confer susceptibility versus resistance vary with the strain of scrapie agent involved and the breed of sheep. Research indicates that QQ sheep are the most susceptible to scrapie infection. QR sheep are much less susceptible and RR sheep appear to be resistant. While the genetic profile for all sheep breeds present in North America has not been determined, the vast majority of positive cases of scrapie that have been genotyped in North America have been determined to be homozygotes for glutamine (QQ) at codon 171. Small numbers of QRs around the world have tested positive for scrapie. In these cases, the amino acids at a second codon (136) are examined and heterozygotes for alanine and valine at codon 136 appear to indicate greater susceptibility among the QR population. Recent reports show a handful of RR positive scrapie cases, details regarding these cases are not currently available.

Recent science indicates that the genotype of the fetus may influence the migration and accumulation of abnormal prion in the placenta of an infected ewe. A 171QQ infected ewe carrying a 171QQ fetus would result in the accumulation of large quantities of abnormal prion, which is then shed during birth or abortion. The abnormal prion does not accumulate to a significant degree in the placenta of a fetus with a genotype 171QR or 171RR. This means that use of a 171RR ram can prevent the shedding of abnormal prion at lambing even from infected ewes.

It is important for producers to understand that scrapie genotyping is NOT disease testing. A 171QQ sheep does not automatically have scrapie, just as it is not an absolute guarantee that a 171RR sheep cannot get scrapie. The CFIA has NO intention to mandate the Canadian sheep flock to breed for scrapie resistance. Scrapie genotyping is a tool that can be used in an overall plan to manage the risk of scrapie on a particular premises. Whether or not a particular producer can or should use scrapie genotyping is a decision based on individual factors such as: breed, prevalence of 171R within the flock, management of ewe flock, and current status of other breeding indices.
Clinical Signs 5. Clinical signs of scrapie rarely develop before the age of 18 months and are highly variable. The majority of cases are diagnosed in animals two to five years of age. As many animals do not show overt clinical signs until late in the course of the disease, significant transmission of the scrapie agent occurs prior to any visible indications of a disease problem. Clinical signs vary considerably, with wasting and debility with or without tremors and incoordination being more prominent features throughout the clinical course of cases of scrapie in Canada.

When present, the predominant nervous signs of scrapie are as follows:

  • tremors and incoordination,
  • a change in mental status (apprehension, teeth grinding, and aggression), and
  • altered sensation (pruritus or itchiness, loss of wool, excoriation and inflammation of the skin, nibble reflex, and excessive licking).
Differential Diagnosis Differential diagnosis to consider in the initial clinical stages of scrapie includes:
  • ectoparasites (lice, mites)
  • hypomagnesaemia
  • pregnancy toxemia (ovine ketosis)
  • rabies
  • listeriosis
  • maedi-visna
  • pseudo rabies (Aujeszky's disease)
  • sarcocystosis
Laboratory Diagnosis 6. Scrapie is diagnosed through the detection of the abnormal prion protein in brain or lymphoid tissue. Tissues to submit for diagnosis include: obex of brain, retropharyngeal lymph nodes, and 3rd eyelid from the live animal. Tissues are sent fixed in formalin and/or fresh frozen depending on test being applied for surveillance cases and the laboratory preference. Various testing techniques may be applied to the tissue; however, immunohistochemistry is the current gold standard testing technology for use on suspect cases. Abnormal prion protein is detectable as early as several months (eight), but consistently in animals over 12 months of age.

Detection of abnormal prions in 3rd eyelid lymphoid follicles has good specificity; however, false negatives (eyelid negative, brain positive animals) are found. To maximize sensitivity, 3rd eyelid testing should be applied to animals with the genotype QQ171 that are over 14 months of age. The test is a useful screening tool for the presence of infection in a flock, but is not a reliable indicator of individual freedom from disease.

Genotyping is a screening test that indicates a sheep’s relative susceptibility for scrapie. When trying to find infection, sheep with the highest susceptibility are the subpopulation in which one is most likely to discover the disease.
Immunity 7. No immune response to scrapie prion protein has been detected.
Public Health 8. Scrapie is not known to be a human health hazard.

7.2 Policy and Principles of Control

Printer friendly PDF version
Policy Statement 1. The Canadian Scrapie Flock Certification Program (SFCP) is a voluntary program, in that producers have a choice whether or not to join the program. However, once participating in the program, compliance with the National Standards is mandatory.

The objective of the SFCP is to provide owners with the opportunity to have their flocks/herds identified as negligible risk with respect to scrapie. Membership in the certification program provides assurances to potential purchasers of animals that a flock/herd is not infected with scrapie. Export certification of scrapie status for countries with higher zoosanitary requirements for scrapie may be based on enrollment and activities under the SFCP. This program also provides a valuable vehicle for surveillance for scrapie within Canada. Any owner of sheep or goat premises who agrees to comply with the SFCP may enroll.
Statutory Authority 2. Scrapie is a reportable disease under the Reportable Diseases Regulations, prescribed pursuant to section 2 of the Health of Animals Act. Any person suspecting an animal of demonstrating signs consistent with scrapie must report that animal to a federal veterinarian at a Canadian Food Inspection Agency (CFIA) district office.
3. The primary role of the federal government in the SFCP is to establish the national standards, as detailed in 7.9 - Appendix 3, and to enforce compliance with these standards.
Principles for Control and Eradication 4. While there are no tests to definitively rule out scrapie in the individual live animal, there are a number of tools that can be used to evaluate the risk of scrapie being present in a sheep flock. These tools have not been established in goats; thus, the only approach to ascertaining the scrapie status in goats is by ongoing herd surveillance. This is achieved by post-mortem testing, the absence of clinical signs, and the prevention of exposure to scrapie over a designated period of time.

There are three different approaches or pathways to follow for a sheep flock to achieve certification status. As with goats, surveillance of mature animals that die, the absence of clinical signs, and the prevention of exposure to scrapie over a designated period of time constitutes the first pathway. A second pathway screens the flock for the presence of scrapie by taking lymphoid follicle samples from the 3rd eyelids of the most genetically susceptible ewes and testing them for scrapie, followed by commencing surveillance of mature animals that die, and preventing exposure to scrapie. The final pathway to certification requires the selection for genetic resistance for scrapie followed by ongoing surveillance of mature animals that die.

A scrapie suspect is any animal which has scrapie as a differential diagnosis.

A scrapie positive animal is any animal in which CFIA confirms the

diagnosis of scrapie by applying the current gold standard test to lymphoid or brain tissues. The current gold standard test is immunohistochemistry.

7.3 Accredited Veterinarian’s Responsibilities

Printer friendly PDF version

Preliminary Activities
1. Obtain and read the terms and conditions for a flock/herd to participate in the Scrapie Flock Certification Program (SFCP) (see 7.9 - Appendix 3).
2. Obtain training and establish an accreditation agreement with your local CFIA district veterinarian.
3. The producer should be advised to contact the SFCP regional administrator, the Ontario Sheep Marketing Agency (OSMA), to obtain an application form and the requirements to participate, advance and maintain certification within each of the three pathways to certification.
4. The accredited veterinarian and producer should discuss which of the three pathways to certification they intend to pursue. Assessment of the facilities, flock/herd management and record-keeping on premises should be done to gauge the ease with which the accredited veterinarian feels the producer can be successful and to identify any changes in record keeping or management that would be necessary to facilitate the fulfilment of SFCP requirements.

General Overview of Responsibilities
5. Accredited veterinarians under this program are responsible for the following:
  • reviewing the requirements of the program and responding to questions of those premises owners applying for or enrolled in the program;
  • teaching the owner to recognize the clinical signs of scrapie, providing information on the epidemiology of the disease and flock/herd management;
  • assessing the facilities, flock/herd management and record-keeping on the premises proposed for membership in the program;
  • assessing the health of the flock/herd to determine whether any sheep/goat is demonstrating signs of scrapie;
  • reporting any suspected case of scrapie to the CFIA district veterinarian;
  • supervising the flock/herd inventory;
  • reconciling records to assure that the flock/herd meets the program requirements (especially purchased animals);
  • signing and submitting reports, including the annual inventory to the status assessor;
  • collecting and submitting blood samples for genotyping, collecting and submitting 3rd eyelid lymphoid follicle samples, and sampling and submitting brain samples if owner requests assistance or teaching the brain and mandibular lymph node sampling technique to the owner.
  • reporting any discrepancies between the program pathway requirements and the occurrences on the premises under their supervision to the status assessor (OSMA).

Producer Responsibilities
6. It is the owner's responsibility to comply with the requirements of the selected pathway of the SFCP (see 7.9 - Appendix 3).

7.4 Procedures Common to All Pathways

Printer friendly PDF version

Preliminary Activities
1. Obtain and read the National Standards for the Scrapie Flock Certification Program (SFCP).
2. Schedule a meeting with the local CFIA district veterinarian to review the terms and conditions for flock/herd certification and to discuss the duties and procedures that must be followed under the selected pathway. Tutorial or review of the TSE brain sampling technique in small ruminants is suggested at this time.
3. Establish a valid accreditation agreement (contract) with the CFIA district office for the delivery of the SFCP.
4. Discuss with the producer which one of the three pathways to certification they intend to pursue. Assessment of their facilities, flock/herd management and record keeping practices should be done to gauge the ease with which the accredited veterinarian feels the producer can be successful and identify any changes in record-keeping or management that would be necessary to facilitate the fulfilment of SFCP requirements.
5. Advise the producer to contact the regional administrator, the Ontario Sheep Marketing Agency (OSMA), to obtain an application form and the requirements to participate, advance and maintain certification within each of the three pathways to certification.

Application
6. The flock owner contacts the regional administrator (OSMA) and requests an application form to participate.
7. An application is completed and submitted to the organization responsible for status assessment. The applicant must indicate which program specific pathway to certification will be pursued. The application form must be accompanied by the following:
  • a site plan of all buildings and grazing premises to which the animals are given access;
  • the initial flock inventory prepared by the accredited veterinarian within the three month period immediately prior to the submission of the application;
  • a record-keeping plan (objective: records must be reviewed completely and effectively at each annual inspection).
8. The application and inventory must be signed by the accredited veterinarian and the producer.
9. The step of applying to the regional administrator (OSMA) for entry into the SFCP is delayed in Pathways 2 and 3 until other conditions are met.

Anniversary Quarter
10. The flock category is effective from the date when the flock is accepted into the program, and the anniversary quarter for subsequent years is the quarter in which the acceptance date falls (January 1 - March 31; April 1 - June 30; July 1 - September 30; October 1 - December 31).

Inventories
11. Supervise the initial animal inventory. All sheep and goats 12 months or older on the premises must bear two forms of identification. All animals aged less than 12 months must be officially identified when a change in ownership occurs or when animals are moved from their usual location (e.g. exhibition, insemination centre, sales barn or auction barn).
12. Assess the animals for any clinical evidence of scrapie.
13. Instruct the owner to record all additions to the flock. Records are required for every sheep or goat that is born on, or that enters the premises.
14. Inform the owner that acquisitions of live sheep or goats or embryos must include documentation required by the specific pathway.
15. Instruct the owner to maintain appropriate documentation of every sheep or goat that leaves the flock/herd, e.g. sales receipts, notation of deaths.
16. Inform the owner that records must be maintained for a period of five years.
Annual Physical Inspection 17. The accredited veterinarian must visit the enrolled premises at least once a year. The physical annual flock/herd inventories must be conducted under the supervision of the accredited veterinarian. Appropriately trained third-party personnel, such as animal health technicians or veterinary students may be used. The inventory will identify every sheep and goat on the premises. During the inventory inspection, all animals over 12 months of age in the flock must be identified individually (individual id read) and assessed for any clinical symptoms of scrapie.
Annual Inventory 18. The annual inventory report is the responsibility of the accredited veterinarian. The foundation of the annual inventory report is the reconciliation of this year’s annual inventory with the previous year’s annual inventory. The annual report lists the following:
  • all identification of each sheep and goat on the premises at the time of the inventory;
  • all identification devices placed on each sheep/goat, including the current lamb/kid crop and any sheep or goat that has lost its identification device;
  • all sheep/goats that have entered or left the premises since the last inventory;
  • the status of the flock of origin for sheep/goats entering the premises as live animals or as implanted embryos;
  • all deaths;
  • the destination of every sheep/goat that moved off the premises as established by a bill of sale or, if the animal has not been sold, a signed document showing the destination of the sheep/goat; and
  • appropriate laboratory results (scrapie testing).

When satisfied that the report adequately documents all reconciliation of the inventory, sign the report.
19. Forward the document to the status assessor within the anniversary quarter in which the enrolled flock/herd was registered in the program.
20. Instruct the owner to submit an application to the regional administrator to advance to the next level of the certification program or to maintain certified status once they have attained that level.

Deadstock Testing
21. Every sheep or goat over 12 months of age that dies on the premises must be submitted for scrapie testing at a CFIA approved laboratory. This is the most critical element of the program and the lack of even one submission without documented cause will jeopardize the flocks’ status within the program. The nearest approved laboratory for scrapie surveillance testing should be identified by both the accredited veterinarian and the producer. The producer may submit the head or brain sample directly to the laboratory. The accredited veterinarian should review how to sever the head and indicate that samples should be stored frozen. Heads/samples may be held and sent, or delivered in batches. If the owner kills a mature sheep for humane purposes, testing is still required. When the brain is too damaged, one head lymph node should be submitted for diagnoses (i.e. the retropharyngeal, mandibular or 3rd eyelid).
22. Flocks that are working through status levels E - A must submit 100% of animals more than 12 months of age that die on farm for scrapie testing. Upon obtaining certified status, the owner may continue to submit 100% of animals more than 12 months of age that die on farm for scrapie testing or, alternatively, they may submit for scrapie testing 80% of animals more than 12 months of age that died and 20% of the animals of the flock more that 12 months of age that are slaughtered.
23. Animals greater than 12 months of age submitted for routine post-mortem examination may be considered as dead submissions if tested for scrapie.
24. No more than five adult animals have to be submitted for testing from a group of animals that die from a common cause, as determined by a veterinarian or veterinary pathologist, within the time frame of the same epidemiologically linked episode (not to exceed four weeks), e.g. toxicity.
Deadstock Testing Exemptions
  • Legitimate exemption from submission of heads.

    The status assessor should consider the following as automatic exemptions from the requirement to submit unless the status assessor suspects the conditions set out were not met or that the exemption is being abused to the detriment of the flock certification program.

    A. Destruction of sheep by fire
    • a certificate or letter of an appropriate fire official must accompany the annual flock report.
    B. Destruction and carrying away the head of a sheep by a predator
    • a certificate or letter of an appropriate wildlife officer or other government official responsible for investigating such incidents must accompany the annual flock report.
    C. Theft
    • a report of the police officer who investigates the theft must accompany the annual flock report.
    D. Loss or destruction of the sample when it is no longer in the control of the owner, e.g. by an accredited veterinarian or laboratory. Recognized laboratories should note on reception of the specimen that the obex is not present and the reason why.
    • a letter setting out the details of the loss of the sample by the individual responsible must accompany the annual flock report.
    E. Any other reason over which the owner could not reasonably be expected to have control which results in the destruction or disappearance of the body, such as a flood
    • a letter or report by an acceptable third party which sets out the details of the reason for failure to submit the sample must accompany the annual flock report.
25. If unsuitable brain specimens are received by a laboratory, the laboratory will notify the status assessor and accredited veterinarian responsible for the flock. A follow-up of the details of the individual situation will be undertaken with the responsible accredited veterinarian / status assessor. If negligence on the part of the producer is identified as the cause, or this occurrence is repeated, the program’s requirements are not considered to have been met and the status of the flock will be suspended.

Sick Animals
26. Instruct the owner of the premises to report illness in a sheep or goat over 12 months of age lasting longer than two weeks, with the exception of a physical injury. The accredited veterinarian will be responsible for monitoring the outcome of the case and for reporting the case to the CFIA if scrapie is a differential diagnosis. Educate the owner to recognize the clinical signs of scrapie and provide information on the epidemiology of the disease.

7.5 Pathway One: Limited Acquisitions Plus Surveillance

Printer friendly PDF version

General Information
1. This is the only pathway available to goats.
2. This is the only pathway currently recognized by the U.S. Department of Agriculture (USDA). Advise the producer that at the current time, pathway one is the only pathway of the Canadian SFCP recognized by the USDA, although this may change in the near future. To maintain this recognition, flocks on pathway one cannot access animals from flocks following certification pathways two and three.
3. All requirements detailed in 7.4 Procedures Common to All Pathways are applicable to flocks/herds participating in this pathway.

Acquisitions
4. Instruct owners that acquisitions of live female sheep or goats and embryos must be accompanied by documentation of the certification level and enrollment date of the flock/herd from which they are sourced/purchased. Discuss with the owner that the impact of acquiring female animals or embryos from a flock or herd of a lower certification level will be the downgrading of their own flock/herd’s level or anniversary quarter. If uncertain of the certification level of a particular Canadian flock or of the equivalence of another country’s program, the accredited veterinarian or producer may obtain this information from the regional administrator (OSMA) or the CFIA.

Advancement
5. The program includes six levels, from the entry level (Level E) to the highest level (Certified). A minimum of five years (one year at each of Level E, D, C, B, and A) is necessary for a registered flock to reach the Certified Level. Once a flock has reached the Certified Level, it maintains this level provided that the applicable requirements continue to be met.

7.6 Pathway Two: 3rd Eyelid Screening Plus Surveillance

Printer friendly PDF version

General Information
1. This pathway is only available to sheep; it is not available to goats.
2. This pathway is not currently recognized by the USDA. Advise the producer that at the current time, this pathway to certification is not recognized by the USDA, although this situation may change in the near future.
3. All requirements detailed in 7.4 Procedures Common to All Pathways are applicable to flocks participating in this pathway.

Pre-application
4. The accredited veterinarian must supervise the collection of appropriate samples for genotyping (7.9 - Appendix 1B) from all ewes greater than 14 months of age. Care must be taken not to contaminate the samples with DNA from other animals. The samples are submitted to a laboratory recognized by the CFIA for scrapie genotyping.
5. When the results of the genetic screening are available, all ewes that are determined to have the 171QQ genotype are to have a sample of lymphoid tissue collected from the 3rd eyelid by the accredited veterinarian (7.9 - Appendix 1C). A minimum of 50 ewes must be tested to continue in this pathway. Instruments into contact with lymphoid tissues should be handled appropriately regarding potential prion contamination and transmission (7.9 - Appendix 1C; 7.9 - Appendix 2).
6. If any laboratory test for scrapie is positive, the accredited veterinarian is to contact the CFIA district veterinarian. The positive animal will be ordered destroyed and confirmatory testing will be conducted on a brain sample.

Application
7. If all laboratory tests for scrapie are negative, the owner must submit an application for enrollment into level B of the SFCP, with all documentation detailed in 7.4 Procedures Common to All Pathways.
8. Compliance with all procedures documented in 7.4 Procedures Common to All Pathways is required upon acceptance into the program.

Acquisitions
9. Acquisitions of live sheep or goats or embryos must include documentation pertaining to the certification level and enrollment date of the flock/herd from which they were sourced/purchased. Discuss with the owner that the impact of acquiring stock/embryo from a lower level flock/herd will be the downgrading of their own flock/herd’s level or anniversary quarter. If uncertain of the certification level of a particular Canadian flock or of the equivalence of another country’s program, the accredited veterinarian or producer may obtain this information from the OSMA or the CFIA.

Advancement
10. To apply to advance to Level A, any breeding females that were purchased from other farms prior to entering the SFCP but were not 14 months or older (thus did not have a 3rd eyelid test) at the time of the first testing, must now be subject to genotyping and 3rd eyelid testing as per steps 2 and 3 above. These results must be submitted along with the annual report and the request to advance to Level A
11. After a minimum of 12 months at Level A, the producer may apply to advance to the Certified Level. Once a flock has reached the Certified Level, it maintains this level provided that the applicable requirements continue to be met.

7.7 Pathway Three: Genetic Selection

Printer friendly PDF version

General Information
1. This pathway is only available to sheep; it is not available to goats.
2. Advise the producer that at the current time this pathway to certification is not recognized by the USDA, although this situation may change in the near future.
3. All requirements detailed in 7.4 Procedures Common to All Pathways are applicable to flocks participating in this pathway.
Assist Producer in Pathway Choice 4. The accredited veterinarian is advised to assist the producer in the decision whether to only genotype rams and pursue selective breeding for resistance using 171RR rams exclusively, whether to genotype all breeding stock to access the 171R available in both the rams and the ewes, or whether they use genetic selection for scrapie resistance at all. This may be an iterative process of testing and decision making. The producer may undertake to test only breeding rams at first. With these results it may be possible to determine if there is a sufficient base of genetic resistance to scrapie to start a breeding program for scrapie resistance without substantial loss of other production traits using only 171RR rams. If there is an insufficient base of genetic resistance in the ram population, the producer may undertake to test the rest of the breeding flock. These results may then be reviewed to determine if there is a sufficient base of genetic resistance across the ewes and rams to breed for resistance to scrapie without substantial loss of other production traits.
Genotype Laboratory Testing 5. A veterinarian accredited to deliver the SFCP must supervise the collection of appropriate samples for genetic testing (7.9 - Appendix 1B). The samples must be genotyped at a laboratory recognized by the CFIA for such purposes (7.9 - Appendix 1D). Samples from 171RR rams must have the genotype confirmed by a second laboratory (only one of the two laboratories has to be recognized by the CFIA for genotype testing). The cost of this verification may be minimized by requesting the first laboratory to forward ONLY the extracted DNA to the second laboratory.

Whole Flock Approach - Application
6. When scrapie genetic testing results document that all breeding animals are either 171RR or 171QR, the owner must submit an application for enrollment into Level A of the SFCP, with all documentation detailed in 7.4 Procedures Common to All Pathways.
7. Compliance with all procedures documented in 7.4 Procedures Common to All Pathways is required upon acceptance into the program.

Whole Flock Approach - Acquisitions
8. Natural increases (home grown replacements): Lambs born from a mating involving at least one 171RR parent may be kept and used as breeding stock without requiring a genotype test.
9. Natural increases (home grown replacements): Lambs born from a mating not involving at least one 171RR parent must be genotyped if to be retained as breeding stock. Only 171RR or 171QR animals may be retained as breeding stock. Animals from non RR matings that are not genotyped must be removed from the flock by 12 months of age. If one of these animals is accidentally bred and lambs on the premises, the flock status will be suspended pending investigation.
10. Acquired replacement breeding stock (purchases/loans): Newly acquired breeding stock must be genotyped as 171RR or 171QR by a laboratory recognized by the CFIA for that purpose (7.9 - Appendix 1D). Semen must be sourced from a ram genotyped as 171RR or 171QR by a laboratory recognized by the CFIA for that purpose (7.9 - Appendix 1D).

Whole Flock Approach - Advancement
11. After 12 months at Level A, the producer may apply to advance to the Certified Level. Once a flock has reached the Certified Level, it maintains this level provided that the applicable requirements continue to be met.

Rams Only Approach - Preapplication
12. Following the producer’s decision to pursue the rams only approach to selection for genetic resistance to scrapie, it will probably take a number of years of ram testing, selection, breeding and culling to assemble an entire flock that can be documented to be offspring from resistant rams. Through this period, the accredited veterinarian’s role will be limited to sampling of the rams for genotyping.
13. Once the producer can document through breeding records that all remaining animals are offspring of a ram genotyped 171RR, the owner must submit an application for enrollment into level A of the SFCP, with all documentation detailed in 7.4 Procedures Common to All Pathways.
14. Once the producer can document through breeding records that all remaining animals are offspring of a ram genotyped 171RR, the owner must submit an application for enrollment into level A of the SFCP, with all documentation detailed in 7.4 Procedures Common to All Pathways.

Rams Only Approach - Acquisitions
15. Acquired replacement breeding stock (purchases/loans): Newly acquired breeding rams must be genotyped as 171RR by a laboratory recognized by the CFIA for that purpose (7.9 - Appendix 1D). Semen must be sourced from a ram genotyped as 171RR by a laboratory recognized by the CFIA for that purpose (7.9 - Appendix 1D). Purchased breeding ewes or embryos must be genotyped as 171RR or 171QR by a laboratory recognized by the CFIA for that purpose (7.9 - Appendix 1D).

Rams Only Approach - Advancement
16. After 12 months at Level A, the producer may apply to advance to the Certified Level. Once a flock has reached the Certified Level, it maintains this level provided that the applicable requirements continue to be met.

7.8 Export Certification

Printer friendly PDF version
1. Animals from flocks/herds enrolled in the Scrapie Flock Certification Program (SFCP) may be certified and endorsed by CFIA as participating in a program which meets the minimum national standards. The CFIA will work to gain international recognition of the minimum national standards. Certificates documenting participation and level in the flock certification program are obtained from the regional administrator, the Ontario Sheep Marketing Agency (OSMA).

Previous / Next


Top of Page
Top of Page		 Important Notices