Monitoring of clinical signs in goats with transmissible spongiform encephalopathies

The sensitivity and specificity of the short clinical protocol in detecting a scrapie case in the scrapie-affected herds was 3.9% and 99.6%, respectively, based on the presence of tremor, positive scratch test, extensive hair loss, ataxia and absent menace response. All BSE- and scrapie-affected goats displayed abnormalities in sensation (over-reactivity to external stimuli, startle responses, pruritus, absent menace response) and movement (ataxia, tremor, postural deficits) at an advanced clinical stage but the first detectable sign associated with scrapie or BSE could vary between animals. Signs of pruritus were not always present despite similar prion protein genotypes. Clinical signs of scrapie were also displayed by two scrapie cases that presented with detectable disease-associated prion protein only in lymphoid tissues.BSE and scrapie may present as pruritic and non-pruritic forms in goats. Signs assessed for the clinical diagnosis of scrapie or BSE in goats should include postural and gait abnormalities, pruritus and visual impairment. However, many scrapie cases will be missed if detection is solely based on the display of clinical signs. PrPd accumulation in the brain appeared to be related to the severity of clinical disease but not to the display of individual neurological signs.Scrapie is a transmissible spongiform encephalopathy (TSE) of sheep and goats. The clinical presentation and progression of scrapie in sheep has been described in detail [1-3] whereas detailed descriptions of scrapie in goats are limited and often based on case reports [4-8] or experimental transmission of ovine or caprine scrapie to goats [9,10]. Similarly, the clinical signs of sheep experimentally infected with the bovine spongiform encephalopathy (BSE) agent have been documented in detail [11,12] but the clinical picture of BSE in goats is less well defined: a short clinical course with ataxia and tremor was reported for intracerebrally inoculated animals whilst orally inocul