March 01, 2003


 Plan expands genetic testing for interstate movement of scrapie-exposed sheep

Posted Feb. 15, 2003

The Department of Agriculture has expanded the use of genetic testing for determining which scrapie-exposed animals can be moved in interstate commerce.

Until now, reclassifying exposed animals for movement on the basis of genotype has been limited to states that had signed pilot project agreements with the USDA Animal and Plant Health Inspection Service. Now, all states will be able to use flock cleanup plans based on genetic testing.

Announced in December, the plan allows owners to retain or sell exposed animals from infected or source flocks without restriction if they have met certain criteria and if genetic testing confirms that these animals are scrapie resistant.

The plan calls for sexually intact sheep not being moved directly to slaughter to be genotyped for scrapie resistance. Genetically susceptible, exposed female animals and, in rare cases, genetically less susceptible, exposed female sheep, will be removed under indemnity or permanently restricted to the farms.

All animals in the flock will be officially identified and entered in the scrapie national genetic database. Animals that are retained will have their genotype confirmed, and the genetically susceptible, exposed animals and the genetically less susceptible, exposed sheep must be identified with a microchip.

A postexposure management and monitoring plan will be required for compliance.

The monitoring plan requires official identification of sexually intact animals that are sold or acquired, a record of any persons from whom sexually intact animals are acquired or to whom they are sold, reporting of any deaths of mature animals and animals showing clinical signs, and annual inspections.

All female genetically susceptible, exposed animals, all those that test positive; and the female offspring of test-positive animals must be removed from the flock. Flocks that remove all susceptible female animals will not be considered exposed flocks once they have completed the flock cleanup plan.

Flocks not removing all susceptible female animals will still be considered exposed. Accordingly, until the monitoring plan is completed, these flocks will have restrictions placed on susceptible animals in the flock and on such animals born or brought into the flock.