October 15, 2003
Oct. 2003 -- The following scrapie question-and-answer piece is the fifth such column to appear in Sheep Industry News. It is being brought to you by the U.S. Department of Agriculture?s Animal & Plant Health Inspection Service, which oversees the National Scrapie Eradication Program. If you have a program-related question you?d like answered, please e-mail it to Sheep Industry News Editor Laura Gerhard at firstname.lastname@example.org, fax it to her attention at (303) 771-8200 or write: ASI; Attn: Laura Gerhard; 6911 S. Yosemite St.; Centennial, CO 80112-1414.
Q: In discussions with sheep producers from other states it seems like there are a lot of variations in how the scrapie program is conducted. Can you explain why this is the case when we are supposed to have a National Scrapie Eradication program?
A: Some states have more stringent regulations than those set by USDA. As a result there are some differences between states. In an effort to minimize differences APHIS will publish the Scrapie Eradication Uniform Methods and Rules (UM&R) this fall. The UM&R will provide uniform guidance for the scrapie program.
Q: If you had to name one core concept from the genetics of scrapie resistance that a producer should remember, what would that be and why do you think it is important?
A: Sheep that test RR at codon 171 are highly resistant to scrapie, sheep that test QR are rarely susceptible and sheep that test QQ are in general susceptible.
Q: There is a lot of information being given to producers about biosecurity these days. What is meant by biosecurity and how does it apply to scrapie?
A: Biosecurity means preventing the spread of infection by controlling the environment and the movement of animals. Scrapie is transmitted primarily by infected placentas and birth fluids to lambs at or near birth. This means the most important thing you can do is to not bring in infected ewes. This risk can be eliminated by maintaining a closed ewe flock. It can be significantly reduced by purchasing ewes of resistant genotype or from flocks that have reached certified status in the Scrapie Flock Certification Program. Lambing management can reduce the risk of spread once scrapie is introduced by lambing ewes separately, cleaning placenta up as soon as possible and by removing all bedding between ewes.
Q: Could you clarify which sheep need to be identified if I am selling market lambs and cull ewes and rams?
A: Ewe lambs moving to slaughter at less than 18 months of age and wethers less than 18 months of age do not require ID. Ewe lambs that may be used as replacements and cull ewes and rams must be identified. If there is any doubt whether a ewe lamb will be slaughtered before 18 months of age, she should be identified.