Ventricular system Flashcards
Label the diagram
Label the diagram
Label the diagram
Explain blood supply to the brain
Cerebral arterial circle (Circle of Willis)
Supply to this structure comes from internal carotid arteries
The arterial circle is joined caudally by Basilar artery
Explain venous drainage of the brain
Veins of brain are valveless & drain into dural venous sinuses
What structures provides cerebrospinal fluid
Choroid plexus in ventricles (mainly lateral)
Examples of TSEs
Sheeps + goats – Scrapie
Deer + elk – chronic wasting disease
Cattle – Bovine spongiform encephalopathy
Cat – feline spongiform encephalopathy
Role of prions in TSEs
Prion = misfolded protein
Self catalytic conversion – causes accumulation -> TSE
Highly stable – protease, heat and UV resistant
Diagnosis of TSEs
Diagnosis:
Transfer of brain extract to permissive experimental animal
Specific identification of the disease specific protein
TSE confirmatory tests:
Immunochemistry and histology
Spongy holes in brain = most likely TSE
Clinical signs of TSEs
Weight loss
Subtle behavioural changes
Licking lips, grinding teeth, scratching (especially in scrapie)
Posture, gait
Ataxia, tremor
Transmission of TSEs
Some are hard to transmit e.g. BSE
Transmitted through medical procedures or ingestion of contaminated feed
Some are easy to transmit e.g. scrapie
Transmitted through direct contact and environmental reservoirs
BSE is zoonotic – epidemic:
Culling, cohort culling (1 animal had BSE, all animals on farm were culled)
Export ban
Feed ban for ruminant material
Older cattle banned from food chain
