Division of the British Veterinary Association
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NATIONAL SCRAPIE PLAN FOR GREAT BRITAIN
Aim
of the National Scrapie Plan
• The objective of the National Scrapie Plan (NSP) for Great Britain is to reduce and eventually eradicate scrapie from the national sheep flock.
•
The NSP has been developed jointly by the Agriculture and Rural Affairs
Departments for Great Britain as part of the Rural Development Plans
for England and Wales and the Agriculture Strategy for Scotland.
What
is the NSP
• The NSP is a voluntary initiative which will initially consist of a breeding programme to increase the number of sheep that genetically are naturally resistant to scrapie. In due course further schemes will be introduced to target scrapie affected flocks and commercial flocks producing lamb for human consumption.
•
The NSP builds upon existing genotyping programmes of individual breed
societies and extensive consultation with industry stakeholders during
the summer of 2000.
Why have a National Scrapie Plan
Advice from independent experts on Transmissible Spongiform Encephalopathy (TSE) diseases such as scrapie and BSE, is that a long-term programme is necessary in order to be able to control and eliminate scrapie. Although there is no known link with human disease, there are a number of good reasons for tackling scrapie in this way now:
• to improve animal health and support trade in British sheep and their products. Several countries (Netherlands, France and the USA) have or are in the process of setting up their own scrapie eradication programmes;
• to protect against the long acknowledged theoretical possibility that BSE might have infected some sheep through contaminated feed. Whilst there is no evidence that BSE has occurred naturally in sheep, this possibility cannot be ruled out and the NSP will help reduce this risk;
• to improve reporting of scrapie which will lead to improvements in animal welfare.
The
use of genetics to tackle scrapie has been recommended by the Spongiform
Encephalopathy Advisory Committee (SEAC), the EU Commission’s
Scientific Steering Committee and is endorsed by the Food Standards
Agency. The Government continues to fund long-term research into the
study of TSEs so that scientific developments and the impact of the
NSP programme on the TSE resistance of the national flock can be closely
monitored.
The
Science behind the NSP
• Studies of the genetics of sheep have shown it is possible to identify whether sheep are resistant or susceptible to TSEs by testing a blood, semen or tissue sample containing the animal’s DNA. This test is called the PrP genotyping test and the result is known as the PrP genotype of a sheep.
The
table below shows the 15 genotypes known to occur in sheep and their
resistance or susceptibility to scrapie.
NSP
Genotypes Table
| Genotype Result |
Consequence
of Genotype Result |
Type |
ARR
/ ARR |
Sheep
that are genetically most resistant to scrapie. |
1 |
|
ARR
/ AHQ |
Sheep
that are genetically resistant to scrapie, but will need careful
selection when used for further breeding. |
2 |
|
ARQ
/ ARH |
Sheep that genetically have little resistance to scrapie. Any
Certificates issued show the date after which the animal cannot
be sold or used for further breeding |
3 |
ARR
/ VRQ |
Sheep
that are genetically susceptible to scrapie and should not be
used for breeding unless in the context of a controlled and NSPAC
approved breeding programme. |
4 |
| AHQ
/ VRQ |
Sheep
that are highly susceptible to scrapie and should not be used
for breeding. |
5 |
This table is subject to continuous scientific review
•
It is recognised that it will take time to change the genetic make-up
of the national flock. To this end, the NSP will initially concentrate
on promoting the use of the ARR gene and excluding the VRQ gene (which
scientific research indicates is the most susceptible to TSEs) and allow
the continued use of sheep with the ARH, ARQ and AHQ genes for a limited
period.
NSP
Schemes and Initiatives
• The first scheme to be launched as part of the NSP in July 2001 was the Ram Genotyping Scheme for Purebred Registered Flocks. This scheme is open to owners of purebred breeding flocks who are registered with a breed society recognised by the National Sheep Association.
• The second scheme to be launched in January 2002 was the Ram Genotyping Scheme for Purebred Non-Registered Flocks. For this scheme there is no requirement for owners to be registered with a breed society.
• A Semen Genotyping Service is available whereby stored semen from rams that are dead or no longer available can be genotyped. The semen must be used in flocks owned by National Scrapie Plan members.
• A one-off Ewe Genotyping Service is being offered to NSP members from December 2002 to March 2003 to help speed up the process of breeding towards scrapie resistance within a flock.
•
For a free copy of the NSP Schemes Brochure, leaflets describing each
scheme or details of how to join the NSP you should phone the National
Scrapie Plan Administration Centre (NSPAC) Helpline on:
0845 601
4858
between
8:30 and 17:00. Calls are charged at the local rate.
Alternatively
you can write to the:
National
Scrapie Plan Administration Centre (NSPAC)
DEFRA
Worcester
WR5 2SU
Further details can also be found on the DEFRA website
