CONTROL OF SCRAPIE EVENTUALLY POSSIBLE

After a brief description of the scrapie situation in the Netherlands, the technical progress made in aspects of scrapie diagnosis is report ed. Emphasis is placed on the use of immuno-histochemistry (IHC) in th e post-mortem histological diagnosis and on the recently published pre clinical test for scrapie, in which IHC is applied to tonsillar biopsi es. These two approaches use the same IHC technique and enable us to c onfirm suspected scrapie in individual animals, and for certain genoty pes even in the preclinical phase. The tonsillar biopsy method could e ventually lead to an infection-or PrPSc-detection method at flock leve l. Further work is required, including validation of the assay for var ious breeds, genotypes, and strains of the agent, and the conversion o f the test into a more practical assay. The article continues with a d iscussion of several scrapie control strategies, describing briefly sc hemes tried in various countries, and elaborates on a proposed scrapie control scheme that could be suitable for the Netherlands, This schem e is essentially based on breeding for resistance, based on PrP genoty ping.