Pathways 2 and 3 of the VSFCP use live animal testing technologies, such as genotyping and/or lymphoid tissue testing for resistance to scrapie in addition to disease surveillance. Certification can be gained in fewer years via this route. However, it is not expected that pathways 2 and 3 will be internationally recognized in the near future.

 

Pathway 2A—This Pathway is not available to goats

A blood sample is collected from all ewes older than 14 months and submitted for genotyping by a CFIA-approved laboratory (a list of CFIA labs completing genotype and live animal tests is available at these laboratories. Samples (e.g. blood samples) required for genotyping must be taken by a veterinarian accredited to deliver the VSFCP or a third party under the supervision of a veterinarian accredited to deliver the VSFCP (e.g. a veterinary student, a technician). All ewes 14 months of age or older, that are determined to have the 171QQ genotype (a genotype that shows little resistance to scrapie), must have a sample of lymphoid tissue collected from the third eyelid by the accredited veterinarian on contract and subjected to testing for scrapie by a laboratory approved by CFIA for that purpose. A minimum of 50 ewes must be biopsied in order to continue in this pathway. If all laboratory tests for scrapie are negative, the flock may officially apply to enter the VSFCP and, if accepted, enters level B.

genotyping for scrapies

 

Pathway 2B—This Pathway is available to goats

A blood sample is collected from all ewes older than 12 months and submitted for genotyping by a CFIA-approved laboratory. Samples (e.g. blood samples) required for genotyping must be taken by a veterinarian accredited to deliver the VSFCP, or a third party under the supervision of a veterinarian accredited to deliver the VSFCP (e.g. a veterinary student, a technician). All ewes 12 months of age or older that are determined to have the 171QQ genotype must have a RAMALT biopsy collected by the accredited veterinarian on contract and subjected to testing for scrapie by a laboratory approved by CFIA for that purpose. A minimum of 50 ewes must be biopsied in order to continue in this pathway. Any does 12 months of age or older must have a RAMALT biopsy taken by the accredited veterinarian on contract and subjected to testing for scrapie by a laboratory approved by CFIA for that purpose. A minimum of 50 does must be biopsied in order to continue in this pathway. If all laboratory tests for scrapie are negative, the flock/herd may officially apply to enter the VSFCP and, if accepted, enter level B.

 

Pathway 3: Whole-Flock Screening—This Pathway is not available to goats

A blood sample is collected from all breeding sheep and submitted for genotyping by a CFIA-approved laboratory. Upon receipt of the results, all breeding females and males that are determined to be 171QQ are removed from the breeding flock. If any of the breeding stock to be retained have been bred, it will be necessary to determine the genotype of their progeny to determine if they may also be retained. After removing 171QQ sheep from the flock, an updated inventory documenting that all remaining breeding sheep are 171RR or 171QR must be conducted under the supervision of a veterinarian accredited to deliver the VSFCP. At this point the producer may officially apply to enter the VSFCP and, if accepted, enter level A.

 

Pathway 3: Rams-Only Screening—This Pathway is not available to goats

A producer starts by selecting breeding rams that are documented 171RR. Over subsequent breeding cycles, cull the flock such that all remaining sheep can be documented (by flock records) to be offspring of a 171RR ram. All subsequent breeding males, be they natural replacements, purchases or loans, must be 171RR. Semen must be sourced from rams genotyped 171RR. All breeding females, other than natural replacements, and embryos must be established by genotyping as 171QR or RR. At this point, an annual inventory documenting the removal of 171QQ and ungenotyped sheep must be conducted under the supervision of a veterinarian accredited to deliver the VSFCP. At this point, the producer may officially apply to enter the VSFCP and, if accepted, enter level A.