Neuro 1 Flashcards
What is the most important thing to do when you start working a case?
PE
Duh.
Whats the difference between peripheral and central nervous system?
Peripheral: outisde of the brain and spinal cord
Central: controls activities of the body (ex. being alive), includes the brain and spinal cord.
How do you avod a misdiagnosis of a rabid animal?
Common sense and everything you’ve learned.
Follow your basic protocols and be safe about it.
Start with PE and work your way through, Hx, Vax Hx.
Ex. Cow foaming from mouth –> Still open their mouths and see whats inside, could be FB.
How do you evaluate CNS signs and localize them?
Predilection sites for FA.
C6-T2
L4-S2
Look for UMN or LMN signs and differentiate them.
Vestibular lesions will show what type of CS?
Circling and head tilt
Frontal lobe lesion will show what type of CS?
Propulsive movement.
Brainstem lesion will show what type of CS?
Distrubed sensorium, blind, seizures.
These guys look possessed, its really sad.
Cortex lesions will show what types of CS?
Consciouness issues.
What are the resposnibilties for these Sites:
Occipital lobe
Basal ganglia
Cerebellar
Occipital lobe: visual reception and interpretation
Basal ganglia: processing link, initiates and directs voluntary mvt.
Cerebellar: Spastic ataxia, dysmetria, tremors
What is Dysmetria?
(English: wrong length) is a lack of coordination of movement typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye. It is a type of ataxia. It can also include an inability to judge distance or scale.
What is the brain stem responsible for?
Neurological fx necessary for survival (for being alive), you can pinpoint gait defecits, and cranial nerve deficits to this location.
Most cranial nerves come from here.
Review Review!!!
the olfactory nerve (I), the optic nerve (II), oculomotornerve (III), trochlear nerve (IV), trigeminal nerve (V), abducensnerve (VI), facial nerve (VII), vestibulocochlear nerve (VIII), glossopharyngeal nerve (IX), vagus nerve (X), accessory nerve(XI), and hypoglossal nerve (XII)
Spinal cord is responsible for what?
Bilateral gait abnormalities and normal mentation.
Lymphoma and abcesses can be associated with this location.
Describe UMN characteristics.
- Initiation of voluntary motor activity
- Maintenance of (anti-gravity) muscle tone and posture
- Control of muscular activity associated with visceral fx
Describe LMN characteristics.
- Efferent neuron of PNS
- Connects CNS with muscles
- Fx of CNS manifested through LMN
- Spinal reflexes
Signs of disease with UMN.
- spasticity (stiffness) and hypertonia
- Loss of inhibition of myotactic reflexes
- Spinal reflexes intact and/ or exaggerated
- loss of voluntary motor fx (paresis or paralysis)
Signs of Disease with LMN
- hypotonia, hyporeflexia
- Muscle weakness (paresis or paralysis)
- Loss of spinal reflexes
- muscle atrophy
- Loss of motor innervation
Hydrocephalus DDX
Bluetongue: present in the US
Akabane: Not in the US, but we are aware of it.
Neonatal calf (born 30 hours ago) presents with blindess followed by seizures.
What is your 1st differential? and if you were to see this in an adult beef cow what can be the cause of these CS?
Vitamin A deficiency. Give the little guy a nice inj, and he will be fine and you’ll be the hero for the day.
Basically low in Vit A interferes with the absoprtion of CSF at the Arachnoid villi.
CSF pressure then builds and it results in blindness followed by seizures (thats the key it follows, can’t have one without the….other!)
In adult beef cows raised on corn stock and no greens they can get papillidema at the optic chiasm.
Cerebellar abiotrophy is an _____________ trait of Herefords and Shorthorns.
Can see with BVD cases that are between __________day gestation.
Autosomal recessive trait
100-200 day
can also see Folial degeneration, cavitation of cerebellum
You are presented with a 45 day old Holstein Friesian female that is recumbant and blind. She is positive for BVD-MD. What is the main CS that she will have on necropsy and how do you DX the BVD?
Cerebellary abiotrophy
Virus neutralization
List the BVD brain lesions
Ocular lesions:
retinal atrophy
optic neuritis
cataracts
micro-opthalmia
retinal dysplasia
Tetanus is brought to you by!
Clostridium tetani
- gram +, anaerobic, spore-forming rod*
- Viable for years*
- Produces and releases toxins (neurotoxin and tetanolysin)*
Which of the following is correct about the pathogenesis of C. tetani?
a. Neurotoxin causes signs called tetanolysin
b. tetanolysin has a tissue necrotizing effect including increased tissue O2, that facilitates bacT proliferation
c. Neurotoxin binds to nerve cell, taken up by endocytosis
d. Moves antegrade down the axon
c. Neurotoxin binds to nerve cell, taken up by endocytosis
Sorry for the dick questions. Look at ppt Neuro 1 slide 31, and you’ll see what I did.
Which of the following is FALSE about the pathogenesis of C. tetani?
a. Nuerotoxin internalizes into interneurons that regulate motor neuron activity.
b. Inhibits action of excitatory neurons
c. Prevents release of glycine and GABA
d. Neurotoxin binds irreversibly
e. Recovery only with growth of new nerve terminals
b. Inhibits action of excitatory neurons
inhibitory neurons! not excitatory….
2 year old Jersey presents with a stiff gait, mild bloat, and difficulty getting up.
Hx shows that that she has never had retained placenta with her calves, or any other abnormal infections. She is housed in a brand new stocking barn, they just installed new rails.
Whats your DDX and why?
She has tetanus.
They installed new rails, someone wasnt careful and probably left a nail around and she stepped on it. Can get tetanus through wound infection: castraion (shes a female so NO), tail docking (shes cute Jersey so No), Puncture wound, retained placenta (look at hx).
Tail can look like a “pump-handle”
5 year old beef bull presents with minimal rumination cycles. Third eye is shown to be prolapsed in both Right and Left eye. Swallowing reflexes are also minimal.
Whats your DDx? Whats causeing those CS?
C. tetani
Prolapsed third eyelid= spasm of retractor oculi muscle
other CS = sardonic grin, pulled back poll, spasm of masseter muscle (lockjaw)
How do you Dx tetanus?
CS: muscle spasms and hyperesthesia
How do you treat tetanus?
- Eliminate Infection: wound debridement, GM +spectrum Abx: PPG BID for 2-3days
- Neutralization of free TeNT: only before uptake into nerve, tetanus antitoxin 1500U-100,000U per animal per day for 3-5 days
- Relief of muscle spasms: tranquilizer- ACEPROMAZINE, muscle relaxant- DIAZEPAM
- Provision of good nursing care: need time for toxin to decay: min stimulation from environment, quiet, dark well padded stall and cotton in the ears, keep sternal to prevent bloat, RUMEN FISTULA
Which of the following is true in the prevention of tetanus?
a. Routine Vax of C. bacterins C and D + tetanus toxoid
b. booster preg ewes/does in early gestaton to protect lamb/kids
c. tetanus antitoxin when castrating/docking: 300-400IU/animal
a. Routine Vax of C. bacterins C and D + tetanus toxoid
What is the vaccine schedules and ages for preventing tetanus?
- at least twice 2 to 4 week intervals
- start around 6wks of age (decline of maternal antibodies)
- booster at 8-10wks
Which of the following is true about Botulism?
a. Decaying vegetation, carrion
b. Endotoxin blocks Ach release and causes flaccid paralysis
c. Only affects one animal in the herd, so its an isolated event
d. Can eat but will have a limberneck
a. Decaying vegetation, carrion
T/F. Vax for Tetanus and Botulism should be given around the same time in order to prevent outbreaks in the herd.
Super false
There is no vax for botulism. There is Tx via antitoxin.
