Abstract
A 19-month-old Corredale ewe suffering from cryptogenic dysstasia from September to November in 1989 was dissected and examined by the histological method. The sheep was smaller than healthy sheep of the same age. At necropsy, no significant gross lesions were found in any of the organs and tissues including the central nervous system. Histopathologically, there were many vacuolated nerve cells and status spongiosus mainly in the brain stem, and this case was diagnosed as being scrapie. Scrapie associated fibril (SAF) proteins were also detected from the brain extract of this sheep using the Western blot analysis. So far, in Japan, there has been no case of scrapie that lacked scratching. Therefore, veterinarians who examine sheep clinically and pathologically should consider such a condition as has been reported here.
