SENILE PLAQUES AND OTHER SENILE CHANGES IN THE BRAIN OF AN AGED AMERICAN BLACK BEAR

A female American black bear (Euarctos ursus americanus) over 20 years old had shown epileptiform neurologic signs starting in March 1992 an d was found dead unexpectedly 8 months later. At necropsy, pulmonary a nd intrabronchial hemorrhage was noted. In the brain, the leptomeninge s exhibited slight thickening, and petechiae were evident in the hippo campus. Histopathologic examination of the brain revealed several seni le changes: numerous senile plaques, amyloid deposition in cerebromeni ngeal arterioles, mineral deposition in the pallidum, and numerous cor pora amylacea in the cerebellum.