Neuro - bovine Flashcards
How do you do a neuro exam on a cow?
General first - TPR, hydration status, rumen function
Cranial nerve deficits
Peripheral nerve deficits
Biochem/haem
What tests do you do to determine cranial nerve function?
Facial asymmetry/loss of sensation
Menace response
Pupillary light reflex
Palpebral reflex
Nystagmus
Strabosmus
Lingual paralysis
Head tilt
What tests do you do to determine peripheral nerve function?
Sensation - pinch digits
Motor control - weight bearing
What are the 4 infectious diseases that cause neurological disorders in cows?
Listeriosis
BSE
Abscesses
Tetanus, botulism - Clostridial diseases
What traumatic disease can cause neurological disorders in cows?
Vertebral trauma
What metabolic diseases can cause neurological disorders in cows?
Ketosis
Hypomagnesaemia
Hypocalcaemia
What toxins can cause neurological disorders in cows?
Ragwort
Lead
Urea
Ryegrass staggers
What type of pathogen is listeria?
Gram positive facultative anaerobe
What causes listeriosis?
Spoiled feed - bad silage or soil in feed
Soil exposure
How does listeria cause neurological disease?
Listeria enters via oral mucosa, goes up trigeminal nerve to brain stem and causes meningoencephalitis
What are the signs of listeriosis?
Dull
Cranial nerve deficits -
Blindness
Head tilt/ear droop
Ptosis
Ptyalism
Normal prehension/mastication
Not circling/ataxic
How do you treat listeriosis?
NSAIDs
Systemic antibiotics - high dose penicillin essential
Nursing
What notifiable disease causes neuro signs in cows?
BSE
What are the signs of BSE?
Apprehension
Hyperaesthesia - kicking when milked
Hind limb motor deficits - ataxia
Change in temperament
Aggression
Compulsive licking
How do you diagnose/manage BSE?
Clinical signs/exclusion of other differentials
Contact APHA
Post mortem for definitive diagnosis
What can cause brain abscesses in cows?
Typically gram positive anaerobes
Dehorning sinusitis
Haematogenous spread
How do you treat brain abscesses?
Antibiotics - long duration
NSAIDs
What tend to cause spinal abscesses?
T. pyogenes
Fusobacterium necrophorum
Haematogenous spread
What can cause vertebral trauma?
Accident eg. stuck in feeder
Bulling injury
What is the treatment for vertebral trauma?
Nursing - lifting, deep straw bed
NSAIDs
What congenital conditions can calves get causing neurological disease?
Viral associated:
BVD virus
Schmallenburg virus
Bluetongue virus
What acquired neurological condition can calves get that is evident from birth?
Cerebral anoxia
What congenital abnormalities does BVD cause?
Internal hydrocephalus
Cerebellar hypoplasia
Poor prognosis
What spreads Schmallenburg virus?
Vector - midge
What does schmallenburg virus cause?
Bite during pregnancy - neuro disease in calf
Bilateral blindness
Ataxia
Recumbency
Inability to suck
Stillborn
Bite before pregnancy - dam immunity
What causes cerebral anoxia?
Prolonged birth/dystocia
What are some neuro conditions of neonatal calves/growing calves?
CCN/thiamine deficiency
Meningitis
Middle ear disease
Hypoglycaemia
Lead poisoning
What neuro disease does bracken cause in cows?
Thiamine deficiency - cerebrocortical necrosis (CCN)
What pathological changes does CCN lead to in cows?
Cerebral oedema
Pressure necrosis due to oedema
Necrosis of cerebral cortex
Fluorescence under UV light
What clinical signs does CCN cause in cows?
Depression
Bilateral central blindness
Ataxia
Muscle tremors
Collapse
What are some differentials for CCN in cows?
Lead posioning
Hypovitaminosis A
Meningitis
Listeriosis
What most commonly causes meningitis in cows/calves?
E coli - from naval/joint ill
Failure of passive transfer
How do you treat meningitis in calves?
Systemic antibiotics - must cross BBB
Amoxycillin
Trimethoprim
NSAIDS
Fluids
What causes middle ear disease in calves?
Ascending infection from respiratory tract - pneumonia
Otitis externa
Mycoplasma bovis
What are the clinical signs of middle ear disease?
Head tilt to affected side
No cranial nerve deficits
What signs do lead poisoning cause? What does it depend on?
Dose
Acute, high exposure - neuro signs
Chronic, low exposure - GI signs
What are the neuro signs of lead poisoning?
Bilateral central blindness
Jaw grinding (bruxism), champing
Head pressing
Seizures
How do you diagnose and treat lead poisoning?
Inform APHA - stop going into food chain
Blood/kidney lead levels
Supportive
Oral salts - precipitate soluble lead
Lead chelating agents
