54-2738. Scrapie-positive animal, defined.
Scrapie-positive animal means an animal for which a diagnosis of scrapie has been made by an approved laboratory through one of the following:
(1) Histopathological examination of central nervous system tissues from the animal for characteristic microscopic lesions of scrapie;
(2) The use of proteinase-resistant protein analysis methods including, but not limited to, immunohistochemistry or western blotting on central nervous system or peripheral tissue samples from a live or a dead animal for which a given method has been approved by the administrator for use on that tissue;
(3) Bioassay;
(4) Scrapie associated fibrils detected by electron microscopy; or
(5) Any other test method approved by the administrator in accordance with 9 C.F.R. 54.10.
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