Cerebrocortical degeneration in goats inoculated with mink-passaged scrapie virus.

Widespread spongiform degeneration of the cerebral cortex occurred in four African pygmy goats that became affected with scrapie after intracerebral inoculation with scrapie virus (Suffolk sheep brain origin) that had been passed three times in ranch mink. The occurrence of such cerebrocortical degeneration was a distinct departure from the topographic pattern of neuropathologic changes that characterizes scrapie in sheep and goats. But the cortical lesion was identical to the one found in goats that became affected with a disease otherwise indistinguishable from scrapie after intracerebral inoculation with transmissible mink encephalopathy (TME) virus that had been passed twice in mink. If TME originated from infection with wild scrapie virus, as is generally thought, then the viruses used in these two instances would be equivalent in their passage history in this aberrant host. Given this similarity, the common occurrence of the cortical lesion is thought to be consistent with the view that TME virus almost certainly is scrapie virus whose biologic properties became altered by chance passage in ranch mink.