31 August 2001

LOTS OF INTEREST IN UKS SCRAPIE PLAN

LAUNCHED last month, the national scrapie plan (NSP) has attracted widespread interest from sheep breeders.

Thousands of breeders have replied to the first stage of the initiative, designed to gauge interest in genotyping to establish flocks resistant to scrapie, according to DEFRAs Colin Penny.

"We have had a steady flow of replies and are in the process of concluding contract details."

Follow-up mailings, providing details of scheme rules and establishing convenient times for blood sampling sheep will be sent out at the end of August. "Blood sampling to establish genotypes should begin in early October," says Mr Penny.

However, there is no deadline on expressing interest or joining the NSP, he says. "Even producers concerned about foot-and-mouth can still express an interest. No blood sampling will be carried out until the flock is in a clear area."

There are 15 possible sheep genotypes which indicate levels of scrapie susceptibility (see panel). For flocks signing up to the plan, breeding policies will be constructed according to genotypes.

Flock owners participating in the scheme will have all stock rams and a proportion of ram lambs genotyped, at no cost, which involves blood sampling sheep and administering an electronic bolus for identification, according to DEFRA.

NSP certificates of genotype will be issued and producers contracted to breed from rams with the more resistant genotypes.

DEFRA will request slaughter of NSP rams with the most scrapie susceptible genotypes within 14 days of detection, according to Mr Penny. "However, where producers wish to fatten the ram, this period will be extended by a further two weeks."

Most rams with scrapie susceptible genotypes will be slaughtered, but where such an animal has a trait of particular importance, it may be possible to negotiate a breeding strategy using this animal.

Currently, prevalence of particular genotypes in different breeds is difficult to predict, he says. "But we should gain an up-to-date picture once we begin blood sampling. A number of breeds which have undertaken commercial blood testing are further down the road than others.

"Eliminating some animals from the breeding population may seem expensive, but the industry must move towards more scrapie resistant animals." &#42

Breeding for scrapie resistance

Genotype Resistance status and breeding policy under the National Scrapie Plan.

ARR/ARR Sheep that are genetically most resistant to scrapie.

ARR/AHQ Sheep that are genetically resistant to scrapie, but will need

ARR/ARH careful selection when used for further breeding.

ARR/ARQ

ARQ/ARH Sheep that genetically have little resistance to scrapie but may

ARQ/AHQ be sold or used for breeding without restriction until the end of

AHQ/AHQ 2004. After this period, any ram on a scheme farm may

ARH/ARH continue to be used for breeding for a further three years

AHQ/ARH except or until the end of its life – whichever is sooner.

ARQ/ARQ*

ARR/VRQ Sheep that are genetically susceptible to scrapie, but may

exceptionally be used for further controlled breeding in the

context of an approved breeding programme.

AHQ/VRQ Sheep that are highly susceptible to scrapie and must be

ARH/VRQ humanely slaughtered or castrated.

ARQ/VRQ

VRQ/VRQ

* Subject to scientific review after the first year