ARS | Publication request: Differences in Production Traits Between Scrapie Resistant and Scrapie Susceptible Ewes

Submitted to: Western Section of Animal Science Proceedings
Publication Type: Proceedings/Symposium
Publication Acceptance Date: March 3, 2003
Publication Date: June 22, 2003
Citation: Proc. Western Sec. Amer Soc Anim Sci 2003, 54:101

Interpretive Summary: Scrapie is a fatal disease of sheep, occurring in most parts of the US. Control measures include removal of all genetically susceptible sheep from infected flocks, surveillance at slaughter, permanent eartagging, and flock monitoring. Scrapie prevention is most readily achieved through selection of disease resistant breeding stock. In this abstract, the authors examined the scrapie susceptibility gene and the production traits in a flock of purebred sheep of various breeds of commercial importance. Although the sample size was small, there was no evidence that scrapie resistance did not appear to influence ultimate lamb production.

Technical Abstract: Scrapie is one of several transmissible spongiform encephalopathies of livestock. Losses to the industry are substantial, due in part to trade restrictions. Disease control consists of removal of genetically susceptible sheep from infected flocks, eartagging for tracing interstate movement of sheep and identification of sheep diagnosed at slaughter. Disease prevention methods include limiting the exposure of susceptible flocks to potentially infected ewes or breeding genetically resistant sheep. However, linkage between the scrapie susceptibility gene PRNP and production traits affecting lamb carcass weight and lamb number have not been examined. In this study, birth weight and weight at weaning was examined for ewes of several breeds, representing the major scrapie susceptibility genes. The scrapie resistant status of the ewe may influence birth-type and weight, but did not appear to influence ultimate lamb production.