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Scrapie and Rare Breeds

1. The Rare Breeds Survival Trust (RBST) represents endangered native breeds of sheep, which are especially vulnerable to disease epidemics because of their low numbers, and to measures designed to control scrapie in the national flock. The National Scrapie Plan (NSP) is a threat to the genetic integrity of breeds represented by the RBST, and exposes some to the possibility of extinction. We welcome the derogations permitted by Commission Decision 2003/100/EC which will allow the most seriously threatened breeds to adopt breeding policies designed to protect their genetic integrity and diversity.

2. We also welcome the commitment by Defra and the devolved authorities to conduct a separate consultation for rare breeds, as agreed at the time of the NSP consultation in the autumn of 2004. The compulsory ram genotyping scheme, which will be applied in 2006, would inflict serious damage on several of the breeds represented by the RBST.

3. 2.1. PrP Genotypes in Rare Breeds. We note the allele frequencies shown in Table 2.1 but endorse the statement (final paragraph) that this information "does not reveal the true impact that the removal of scrapie susceptible animals might have on rare sheep breeds".

4. 2.2. Assessment of the Impact that Breeding for Resistance might have on Rare Sheep Breeds. The study carried out by Roden and Townsend on rare breeds included recommendations for action with each breed, and these are summarised (Table 2.2). We agree the broad principle of the recommendations.

5. While we agree with the generality of the recommendations, there are individual points which require modification or correction. It is not possible to reconcile the categorisation for some breeds with the population data available for them. For example, Group A in Table 2.2 qualify by virtue of Ne <50. However the classification was determined by data which is now out of date. It is imperative that valid and up to date data are used, and current data indicates that other breeds should qualify (e.g. North Ronaldsay, Teeswater, Leicester Longwool) for 'Exempt' status, and one, Oxford Down, no longer falls into this category.

6. The standard procedure for calculating Ne is based on the system of ‘random breeding'. However, breeds of farm livestock are selectively bred leading to greater influence of some lines, and this will produce a lower Ne.

7. We welcome and endorse the statement that "alterations to the RBST Watchlist will be reflected in any subsequent derogation that is applied", and recommend that the most recent data are used with regard to rare breeds.

8. 3.2.1. Level of ARR within a breed. We strongly endorse the statement (final paragraph) that "we do not feel that applying a derogation based on the level of the ARR allele would be the most appropriate way forward for the majority of native rare breeds". It has been suggested that the % frequency of the VRQ allele would be a better criterion, but even this is not entirely adequate. We recommend that the number of rams which would remain (genotype categories 1, 2 and 3 (i.e. absence of VRQ)) after removal of those from genotype categories 4 & 5 is the best criterion. It is a direct measure of the breeding stock that would be available. On this basis a number of breeds which are low in number would have insufficient rams available to maintain Ne so should have high priority for exemption.

9. 3.2.2. Definition of 'lost to farming'. We note that this definition has been determined by the EU (Regulation 445/2002) on the basis of recommendations from EAAP, and has been set at 10,000 breeding ewes. We consider this is not appropriate for conditions in the UK as, firstly, it should be applied on a EU-wide basis and, secondly, it includes breeds which are thriving in the mainstream industry (e.g. Hampshire Down) and their inclusion is incongruous.

10. 3.2.3. Number of breeding ewes. The RBST Watchlist applies a numerical criterion of 3,000 breeding ewes as the maximum for inclusion, and eight breeds are listed in Table 3.1 which fall between 3,000 and 10,000 breeding ewes. None of these are Watchlist breeds, and therefore the issue does not affect us directly. However, we note that the survey by Pollott et al is being referenced, and it must be noted that this survey includes unregistered animals which can not make a contribution to the ongoing conservation and diversity of the breed, and therefore should be excluded.

11. 3.3. Issues for Comment. With regard to the specific points:

1. We agree the definition of 'danger of being lost to farming' is appropriate for rare breeds.
2. We agree that Defra and the devolved authorities should continue to work on the basis of breeds listed by the RBST.
3. N/A
4. We would expect non-native breeds to be protected in their country of origin.

12. 4.1. Options. We support the adoption of Option 3.

Robert Terry
Executive Director

20th January 2006

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