Clinical Flashcards
What does DAMNIT V stand for?
D - degenerative
A - anomalous
M - metabolic
N - nutritional
I - Inflammatory, infection, idiopathic
T - traumatic, toxic
V - vascular
What is the purpose of DAMNIT V?
To create a differential diagnosis list
What conditions can be confused with seizures?
Epilepsy
Stroke
Tetanus
Intoxication
What are some clinical signs of BSE in cattle?
What is BSE?
Why is it really hard to diagnose?
Bovine Spongiform encephalopathy - Mad cow disease
Clinical signs may not present until years after infection
What causes BSE?
What caused the BSE outbreak?
How are cattle tested?
Who do you report a suspected case to?
Proteins called prions, they are abnormal and harmful
Prions found in meat-and-bone meal from sheep and cattle that was prion infected
Once dead their brain is tested using the BSE rapid screening test (ELISA)
APHA (England, Scotland, Wales (NI is regional))
What are the 3 main components of the CNS and what are the main clinical signs associated with them?
Brain = change in mental activity Brainstem = cranial nerve damage
Spinal cord = abnormal limb movement
Give definitions for the following mentation states:
Normal
Depressed
Obtunded
Stuporous
Comatose
Other
Normal: Animal alert, apprehensive and curious during examination
Depressed: Animal awake, not alert to surroundings, uninterested in normal stimuli (not always neurological)
Obtunded: Animal dull, slow to respond, still responds appropriately
Stuporous: Animal unresponsive to normal stimuli, aroused with strong stimuli
Comatose: state of unconsciousness, animal cannot be aroused even with harmful stimuli (emergency)
Other: abnormal behaviour, disorientated, delirious, aggressive, head-pressing, fly biting, tail charing, circling
What are clinical signs of brain disease?
- reduced alertness
- head-pressing
- teeth grinding
- irritability
- blindness
seizures - circling
- head turn
- ataxia
- sensory processes heightened
What are signs that there is an issue with the cortex?
Limb and movement deficit
Abnormal behaviour
What are clinical signs of cerebellar disease?
Is the common in horses?
- head tremors, bobbing
- exaggerated gaits (hypo/hypermetria*) = symmetric ataxia without weakness
- absence of menace response
- irregular nystagmus (vertical + horizontal)
No, very rare apart from in Arabs
*Under and over exaggeration of movement
What goes wrong clinically if there is an issue with the cerebellum?
Its a fine tuning organ so it ensures movements are exact so animals struggle to co-ordinate themselves and will have either short or exaggerated movements often missing they target
What are all head movement issues usually caused by?
Issues with the cranial nerves
What is the difference in impact between peripheral and central lesions/diseases when it comes to the cranial nerves?
Peripheral (whee the nerve ends up) = only 1 damaged
Central (all the nerve roots close together) = impacts multiple nerves
How would you test, in a horse, that there was an issue with the olfactory CN (l)?
Put smelly sweet food in your pocket and see if the horse is interested and trying to get into your pocket.
What 3 tests, in a horse, would indicate that there was an issue with the optic CN (ll)?
- Menace response
- Pupillary light reflex
- Dazzle Reflex
As well as the optic nerve what parts of the brain are used during the menace response?
The cerebellum and the cortex, indicated when the horse moves it head away
Would the menace response work on a foal before 14 days of age?
No, this is a learned response so is absent for the first 14 days of life
What nerve does the pupillary light reflex test?
The oculomotor CN (lll) due to the pupil constricting
What nerve can you accidentally check during the menace response if not done properly?
If there is air sensation on the skin, this triggers the trigeminal nerve (V)
What nerve and part of the brain does the dazzle reflex check?
The facial nerve and the subcortical areas of the brain (mid-brain), causes blinking in both eyes
What is the purpose of a guttural pouch in horses?
Reduces weight in the horses head and heat during exercise
Why can the guttural push lead to issue with the cranial nerves?
Some run along the back of it (so issues can start here instead of the brainstem)
