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Clinical Neurology > Adult Equine: Nervous System Diseases > Flashcards

Adult Equine: Nervous System Diseases Flashcards

1
Q

What are the possible DDx of Intracranial Diseases?

A
  • Head trauma
  • Ischemia
  • Infection: Meningitis or Encephalomyelitis
  • Space occupying lesions
  • Toxins
  • Narcolepsy
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2
Q

What are the most commonly affected areas of the skull with head trauma in the horse?

A

Adults: petrous temporal bone, basi-occipital bone and basi-sphenoid bone are all common areas of fracture due to rearing up and hitting the back of the head

Foals: entire skull due to being kicked by the foal

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3
Q

What are the clinical signs associated with head trauma in the horse?

A
  • Neurological signs are usually immediate
  • Cerebral signs: depression, dementia, excitation or recumbent

+/- brain stem/ cranial nerve signs: head tilt or facial nerve paralysis

  • Epistaxis: bleeding into guttural pouches or sinus trauma
  • Bleeding from the ear
  • Seizures: can be facial grimacing, twitching, rapid eye movements or blinking, paddling, tonic posturing or extensor rigidity
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4
Q

You notice a horse is having seizures (anything including facial grimacing, twitching, rapid eye movements or blinking, paddling, tonic posturing or extensor rigidity), what is the treatment of choice for seizures in the horse?
What are the other treatments available?

A

Treatment of choice:
- Diazepam: 0.02 - 0.2 mg/kg IV

Other:

  • Phenobarbital: 12-20 mg/kg IV in 30mls saline, then 2.2-11 mg/kg PO SID-BID
  • NSAIDs or Steroids
  • Stall padding to prevent further injury

Caution: NO Acepromazine or Ketamine!

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5
Q

What is the prognosis of seizures in horses?

A

Prognosis is guarded in adult horses as they are difficult to manage, and involvement of the cranial nerves worsens the prognosis, especially if chewing or swallowing is affected

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6
Q

What are the most common causes of brain ischemia in the adult horse?

A

1) Anesthesia/ Post-anesthesia due to hypoxic or hypercapnic periods
note: damage can be focal or extensive

2) Intra-carotid Injection: the common carotid artery is very close to the jugular vein (reactions will occur in 5-30 seconds post-injection)

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7
Q

What are the clinical signs associated with brain ischemia in the horse following anesthesia?

A
  • Blindness
  • Abnormal behavior: altered mentation/ behaviour
  • Seizures
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8
Q

What is the treatment for suspected brain ischemia in the adult horse, due to hypoxia/ hypercapnia post-anesthesia?

A
  • Supportive: provide oxygen, and stall padding

- Control seizures with Diazepam

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9
Q

What is the prognosis associated with brain ischemia in the adult horse?

A

Guarded to poor- depending on the areas of the brain affected and if there is cranial nerve involvement, especially if chewing and swallowing is affected

Intra-carotid injection with:

  • Xylazine (water-soluble): the horse generally regains consciousness within an hour and recovers completely in a week = good prognosis
  • Procaine penicillin (oil-based): may warrant euthanasia due to cerebral damage
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10
Q

What is the treatment for suspected brain ischemia in the adult horse, due to intra-carotid injection?

A
  • Supportive: provide oxygen, and stall padding

- Control seizures with Diazepam

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11
Q

What is the most common cause of meningitis in the adult horse?
What is the prevalence of meningitis in the adult horse?

A

Usually bacterial spread hematogenously from another site of infection

Prevalence: uncommon in adults

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12
Q

What are the clinical signs associated with meningitis in horses?

A
  • Depression
  • Coma
  • Cervical stiffness
  • Seizures
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13
Q

How can Meningitis be diagnosed in the horse?

A
  • Blood-work
  • CSF cytology + culture
  • Blood culture
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14
Q

How can Meningitis be treated in the horse?

A
  • IV broad-spectrum antibiotics (4-6 weeks minimum) based on culture + sensitivity
  • NSAIDs or steroids + supportive care + Control seizures with Diazepam
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15
Q

What infectious agents can cause Encephalomyelitis in horses?

A
  • Eastern, Western and Venezuelan Equine Encephalitis viruses
  • West Nile Virus
  • Rabies
  • Borna Disease Virus
  • Equine Herpes Virus-1
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16
Q

What are the clinical signs associated with Encephalomyelitis in horses?

A
  • Fever, anorexia, stiffness
  • Paralysis of larynx, pharynx and tongue
  • Propulsive walking and depression
  • Dog-sitting leading to recumbency

note: Equine Herpes Virus-1 is usually ascending, thus will start in the hind end with urinary incontinence and work its way up

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17
Q

What is the treatment for Encephalomyelitis in horses?

What is the prognosis of Encephalomyelitis in horses?

A
  • Supportive care
  • Anticonvulsants
  • Steroids
  • Anti-viral drugs can be tried: acyclovir and valacyclovir

Depends on the offending agent:

  • WNV and EHV = guarded to poor
  • Others = guarded to grave
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18
Q

What are the usual causes of Space-occupying masses in the equine skull/ brian?

A
  • Abscess: usually a form of bastard Strangles
  • Granuloma
  • Neoplasia: lymphosarcoma or melanomas

+/- Hydrocephalus if the space-occupying lesion obstructs the flow of CSF

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19
Q

How can space-occupying masses be diagnosed in the equine skull/ brain?

A

CT or MRI

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20
Q

What are the toxins that can lead to neurological signs in the horse?

A
  • Ragwort poisoning: leading to hepatic encephalopathy
  • Mycotoxins: leading to grass staggers
  • Fusarium B: leading to Mouldy Corn Disease
  • Yellow Star Thistle
  • Lead
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21
Q

How can toxicity be treated in the adult horse?

A
  • Remove the offending toxin by removing it from the diet/ pasture
  • Supportive care
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22
Q

What is the cause of Narcolepsy in horses?

A

The current thought is due to a lack of sleep

  • Perhaps a dominant animal in a group feels it can’t fall asleep to protect the group
  • Maybe the animal has pain and is unable to sleep or lie down
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23
Q

What are the clinical signs associated with Narcolepsy in the horse?

A
  • Episodes up to 10 minutes: usually occurring during grooming, hosing down after exercise, eating/ drinking, or being pet
  • Most remain standing with a low hanging head and closed eyelids
  • Horses may buckle to their knees or fetlocks and develop pressure sores here
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24
Q

What is the treatment of Narcolepsy in the horse?

What is the prognosis of Narcolepsy in horses?

A
  • No real treatment, but if the cause of the sleep deprivation is pain, then a Bute trial can be done

Prognosis:

  • Young horses may grow out of it
  • Life long problem in adults and thus safety for both the horse and the owner need to be considered e.g. don’t want the horse to fall on you while you are grooming it
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25
Q

What is the treatment for Facial Nerve Paralysis in the adult horse, post recumbency?

A
  • Topical anti-inflammatory: Voltarol

- Eye lube IF the lacrimal nerve has been affected too

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26
Q

What causes Horner’s Syndrome in the horse?

A

Damage to the ascending sympathetic nerves in the vago-sympathetic trunk (sits in the jugular groove)

Most commonly associated with:

  • Perivascular injections, where the injection is accidentally placed around the jugular vein, putting pressure or blocking the impulses along the vago-sympathetic trunk
  • Guttural pouch disease, where the cranial-cervical ganglia sits on top of the dorsal part of the guttural pouch
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27
Q

What are the clinical signs of Horner’s Syndrome in the horse?

A
  • Miosis: pupil constriction
  • Enopthalmos: posterior displacement of the eyeball
  • -> + prolapsed 3rd eyelid in these cases
  • Ptosis
  • Sweating of the neck of the side of the lesion
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28
Q

What is the cause of Tempero-hyoid osteopathy in horses?

A
  • We used to think it was due to an extending infection from the otitis media
  • We now believe it is due to Degenerative Joint Disease in the Tempero-hyoid joint with bony proliferations forming
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29
Q

What are the clinical signs associated with Tempero-hyoid Osteopathy in horses?

A
  • Behaviour changes: head shaking, ear rubbing, and avoiding the bit
  • If a stress fracture forms because of it, this can lead to facial nerve paralysis, corneal ulceration (lacrimal nerve involvement), and peripheral vestibular syndrome
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30
Q

How can Tempero-hyoid Osteopathy in horses be diagnosed?

A
  • Radiography of the Tempero-hyoid joint
  • Endoscopy of the Guttural Pouch
  • CT
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31
Q

What is the treatment of Tempero-hyoid Osteopathy in horses?

A
  • If the cause is due to DJD of the Tempero-hyoid joint + Boney proliferation: NSAIDs + Prophylactic surgery of the hyoid apparatus may be indicated to prevent a stress fracture from occurring
  • If the lacrimal nerve branch of the facial nerve is involved, then eye lubrication will be needed
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32
Q

What is the prognosis of Tempero-hyoid Osteopathy in horses?

A
  • Fair to guarded for athletic performance

- May get residual deficits of CN 7 and 8 and therefore even casual riding may be risky

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33
Q

What is Cauda equina neuritis (aka polyneuritis equi)?

A

A chronic granulomatous inflammation of the cauda equina, thought to be due to an immune-mediated condition.
This condition can involve more nerves than just the cauda equina (such as the cranial nerves/ brachial plexus) and therefore was renamed Polyneuritis equi

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34
Q

What are the clinical signs/ presentations of horses with Polyneuritis equi?

A
  • Hyperesthesia, analgesia or areflexia of the perineal area
  • Paralysis of the tail, anus and perineum
  • Paralysis of the rectum + bladder: leading to impactions and chronic cystitis

+/- CN signs of 5, 7 and 8 or the brachial plexus
+/- Pelvic limb ataxia, weakness or muscle atrophy: uncommon

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35
Q

How can Polyneuritis equi be diagnosed?

A

There is no Ante-mortem tests available, so the diagnosis is based on clinical signs and ruling out other conditions (e.g. Sacral fracture)

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36
Q

How is Polyneuritis equi treated?

What is the prognosis of Polyneuritis equi?

A

Tx: Supportive and non-specific, treat the horse depending on the signs e.g. treat the incontinence or UTI’s

Prognosis:
- Poor: this is a progressive disease and may progress rapidly or slowly

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37
Q

What are the DDx of the spinal cord diseases in the horse?

A
  • Trauma
  • Infection: Osteomyelitis
  • Cervical vertebral malformation/ cervical stenotic myelopathy (Wobbler’s Syndrome)
  • Verminous Meningoencephalomyelitis
  • Equine herpesvirus-1 myeloencephalopathy
  • Equine Degenerative Myeloencephalopathy
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38
Q

What are the common sites of trauma along the spine of the horse?

A

1) Occipito-atlanto-axial region: due to rearing up and falling back, or neck hyper-flexion, leading to fractures or avulsions of the rectus capitus muscle, where it attaches to the occipital bone
2) Caudal cervical region: due to neck hyper-flexion
3) Mid-thoracic to cranial lumbar back: due to falling on its back (usually due to jumping accidents)
4) Sacral region: due to a fall after rearing up, or running backwards into a wall

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39
Q

What are the clinical signs/ presentations of a traumatic spinal injury in the horse?

A
  • Sudden onset of reluctance to move
  • Ataxia and weakness
  • Recumbency
  • Pelvic limb gait abnormalities
  • Abnormalities of urination or defecation
  • Tail/ Perineal hypo-reflexia and paralysis
40
Q

What is the treatment of a traumatic spinal injury in a horse?

What is the prognosis of a traumatic spinal injury in an adult horse?

A

1) Stabilization: sedation, airway access, looking for bleeding, control circulation/ treat shock,
2) Decrease swelling associated with the spinal trauma: Steroids, Mannitol, NSAIDs, Furosemide
3) Time + Rest
4) +/- Surgery if needed (uncommonly done)

Prognosis:

  • If the horse is recumbent for 24+ hours = grave. It’s just too difficult to manage a recumbent adult horse (turning the horse to prevent pressure sores)
  • Repeat neuro exam to guide prognosis
  • A sacral fracture should improve by 12 weeks, if not then the prognosis is poor
41
Q

How can traumatic spinal injury be diagnosed in the horse?

A

1) History, clinical exam, physical exam, rectal exam
2) Neurological exam
3) Radiograph/ CT
4) U/S: of the neck and pelvis

42
Q

What are the most common causes of a spinal infection (vertebral osteomyelitis/ diskospondylitis)?

A
  • Hematogenous spread from a distant infection
  • Open Wound
  • Injection abscesses
43
Q

What are the clinical signs associated with a spinal infection (vertebral osteomyelitis/ diskospondylitis) in the horse?

A
  • Stiff + painful neck
  • Fever
  • Ataxia due to pressure on the spinal cord
44
Q

How can a spinal infection (vertebral osteomyelitis/ diskospondylitis) be diagnosed in the horse?

A
  • Bloodwork: Neutrophilia + High Fibrinogen
  • Cervical radiographs
  • CSF Tap, culture + cytology
  • Blood culture
45
Q

What is the treatment for a spinal infection (vertebral osteomyelitis/ diskospondylitis) in the horse?

What is the prognosis?

A
  • Broad-spectrum antibiotics, guided by culture and sensitivity
  • NSAIDs
    +/- Surgical exploration + debridement

Prognosis:
Fair to Poor

46
Q

What is the layman’s term for Cervical Vertebral Stenotic Myelopathy?

A

Wobbler’s Syndrome

47
Q

What is the proper term for Wobbler’s Syndrome?

A

Cervical Vertebral Stenotic Myelopathy

48
Q

What happens in Wobbler’s Syndrome that leads to its clinical signs/ presentation?

A
  • Cervical vertebral malformation results in progressive spinal cord compression and injury, leading to ataxia and paresis (wobble)
49
Q

What are the 2 theories behind why Wobbler’s Syndrome happens in horses?

A

1) Type 1 = Developmental: a disorder of bone/ cartilage development leading to cervical vertebral malformation

2) Type 2 = Acquired Biomechanical: abnormal mechanical stresses deform the cervical column resulting in stenosis of the canal
- The equine vertebrae growth plates are susceptible to biomechanical stresses until ~5 years old when they eventually close

In reality it’s probably a mix of both

50
Q

When a horse develops Wobbler’s Syndrome, there are 2 possible manifestations of it, what are they?

A

1) Dynamic instability: this is a dynamic compression, where there is unstable articulation between C3-C5, leading to a narrowing of the canal during cervical ventroflexion (head down)
The spinal cord becomes compressed and blood vessels are pinched or ruptured

2) Static stenosis: Regardless of the head/ neck position, you get narrowing of the canal due to thickening of the dorsal laminae bone + hypertrophy of the ligamentum flavum

51
Q

An 8 - 18 month old, fast-growing male Thoroughbred presents with Wobbler’s Syndrome, which manifestation is most likely in this case?

A

Type 1 = Dynamic Instability: dynamic compression leading to narrowing of the canal during cervical ventroflexion (head down)

52
Q

How can Wobbler’s Syndrome be diagnosed in the horse?

A
  • Clinical signs
  • Radiographs
  • Myelogram
53
Q

What is the treatment of Wobbler’s Syndrome in the horse?

A
  • Rest
  • Nutritional management if the horse is still young and has growing to do
  • Surgical Intervention to stabilize adjacent bones is becoming more popular
  • NSAIDs
54
Q

What is Verminous Meningoencephalomyelitis?

A

Inflammation of the CNS + meninges due to the migration of strongyles and parascaris species of nematodes

55
Q

What are the clinical signs associated with Verminous Meningoencephalomyelitis?

A

Depends on the site that is affected, but often includes: ataxia and non-specific clinical signs

56
Q

How can Verminous Meningoencephalomyelitis be diagnosed?

A
  • Exclusion of other diseases
    +/- peripheral eosinophilia (this is not always seen though)
    +/- High Fecal Egg Count
57
Q

If Verminous Meningoencephalomyelitis is suspected, what is the treatment?

A

Anthelmintics + NSAIDs

  • Fenbendazole (50-60 mg/kg SID 1-3 days)
  • Thiabendazole (440 mg/kg SID for 2 days)
  • Ivermectin (0.2 mg/kg, once)
58
Q

What is the causative agent of Equine Protozoal myeloencephalitis (EPM)?

A

Sarcocystis neurona

59
Q

What are the clinical signs associated with Equine Protozoal myeloencephalitis (EPM)?

A
  • Usually 1-6 years old
  • More common in North and South America + Canada
  • Asymmetric cranial deficits

Most common Presentation are the 3A’s: Asymmetric, Ataxic and focal muscle Atrophy

60
Q

How can you confirm the presence of Sarcocystis neurona?

A

1) Immunoblot analysis
- S. neurona antibodies in serum and CSF
CSF: Sn and Sp of 89%
Serum: Sn of 89% and Sp of 71%: BUT almost all horses will have antibodies for the parasite due to previous exposure but wont necessarily develop clinical signs

2) ELISA: Highly specific for S.neurona specific antibodies
note: You cannot do a PCR, its sensitivity is very low as Merozoites are not found in the CSF, and any free parasite DNA floating around is rapidly destroyed
3) PM: Acute hemorrhagic lesions and necrosis in the spinal cord

61
Q

What is treatment for S. neurona in horses?

A
  • Ideal drug: Ponazuril: Antiprotozoal Oral Paste, 5mg/kg/day ~28 days
  • Sulfonamides: Sulfadiazine orally, 20mg/kg
  • Diclazuril and Toltrazuril: coccidiostat that kills parasites in early stages, used as a prophylactic
  • NSAIDs
  • Vitamin E

Caution: steroids are contraindicated in this case

62
Q

What is the pathophysiology as to why neurological signs are seen in horses with Equine Herpesvirus-1?

A

The virus causes vasculitis of the CNS arterioles, leading to edema and pressure on the NS
Can also cause hypoxic damage to the NS tissue

63
Q

What are the clinical signs associated with neurological Equine Herpesvirus-1?

A
  • Usually adults are affected (4+ years old)
  • Often starts with respiratory signs
  • acute hindlimb paresis + Dog sitting
  • Urine scalding (bladder paresis)
    +/- Cranial nerve signs
64
Q

How can Equine Herpesvirus-1 be diagnosed?

A
  • CSF Tap
  • Virus isolation in the serum
  • Titres
65
Q

What is the treatment for Equine Herpesvirus-1?

What is the prognosis?

A
  • Isolate the animal: it is highly contagious
  • NSAIDs or Steroids (Dex 0.1 mg/kg)
    +/- Antibiotics to clear secondary infections
  • Urinary catheter to prevent urine scalding

Prognosis:
- Most horses will recover completely IF they were never recumbent

66
Q

What is Equine Degenerative Myeloencephalopathy (EDM)?

What causes EDM?

A

EDM is a condition characterized as a symmetric non-compressive spinal cord disease with degeneration of the white and grey matter

  • Cause is Unknown: May be due to Vit E deficiency +/- genetic predisposition

It is a potential DDx for Type 1 Wobbler’s in young horses

67
Q

What is the treatment for Equine Degenerative Myeloencephalopathy (EDM)?

How can EDM be prevented?

A

No treatment as we are unsure what causes it

Prevention:
Provide plenty of green forage to growing horses

68
Q

What are the clinical signs associated with Equine Degenerative Myeloencephalopathy (EDM)?

A

Ataxia and paresis (wobbling)

- Same as Wobbler’s Syndrome

69
Q

What are the DDx for peripheral nerve disease in the horse?

A
  • Trauma
  • Equine Motor Neuron Disease
  • Grass Sickness
  • Tetanus
  • Botulism
  • Stringhalt
  • Shivering
  • Headshaking
70
Q

What is the pathogenesis of Equine Motor Neuron Disease?

A

Unknown, but thought to be related to Vit E deficiency

71
Q

What can be seen on a histopathological sample of a horse with Equine Motor Neuron Disease?

A
  • Destruction of motor nerve cell bodies in the brainstem nuclei and ventral horn grey matter, resulting in denervation atrophy of the muscles with a high percentage of Type 1 fibres (these are the slow contracting and oxygen utilizing muscles)
72
Q

What are the clinical signs associated with Equine Motor Neuron Disease?

A
  • Usually older horses with weight loss and a NORMAL appetite
  • NO ataxia
  • Postural weakness
  • Short stride/ stumbling when moving
  • When standing muscle fasciculations can be seen
  • Muscle atrophy eventually develops +/- excessive recumbency
  • Horses often position their feet under them to stabilize themselves (“elephant on a ball”)
73
Q

How can Equine Motor Neuron Disease be diagnosed?

A
  • Clinical signs
  • Opthalmic Exam: Retinal hyperpigmentation is often seen
  • Definitive diagnosis = Biopsy from the sacro-caudalis dorsalis medialis muscle (it is just beside the tail-head)
74
Q

What is the treatment for Equine Motor Neuron Disease?

What is the prognosis?

A

No specific treatment
- Often Vit E supplementation is given

Prognosis: poor to guarded

75
Q

Where are the most common locations of trauma to the peripheral nervous system?

A
  • Supra-scapular nerve: leading to paralysis of the infraspinatus and supraspinatus muscles
  • Brachial plexus: leading to a flaccid biceps, triceps and pectoralis = flaccid limb
  • Radial nerve: leading to a dropped elbow and failure of protraction + flexed distal limb joints
  • Cranial gluteal nerve: leading to gluteal muscle atrophy
76
Q

What is the cause of Equine Grass Sickness?

A
  • Suspected: Clostridium botulinum type C toxin

Leading to widespread destruction of the autonomic ganglia (including the myenteric and submucosal plexuses, the cardiac ganglia and the CNS ganglia)

77
Q

What are the clinical signs associated with Equine Grass Sickness?

A

Signs of parasympathetic dysfunction:

  • Dysphagia
  • Constipation
  • Colic
  • Bloat
  • Inappetance
  • Weight loss
  • Tachycardia
  • Sweating
  • Rhinitis sicca
78
Q

How can Equine Grass Sickness be treated?

What is the prognosis?

A

Tx: supportive

Prognosis: guarded to poor = high mortality rate

79
Q

What is the causative agent of Tetanus?

A

Clostridium tetani toxins

80
Q

What is the pathophysiology of tetanus?

A
  • C. tetani gets into a wound
  • It releases its toxins
  • The Tetanospasmin toxin is absorbed and carried to the pre-synaptic part of the motor endplate
  • The toxin is transported to the CNS along the motor neurons to the ventral horn
  • The toxin crosses the synaptic cleft to the presynaptic inhibitory interneurons
  • It will inhibit the release of glycine and GABA
  • This inhibits INHIBITION! Leading to Hypertonia and Muscular spasms
81
Q

What are the clinical signs associated with Tetanus in the horse?

A

Generalized spasticity by 24 hours

  • stiff gait, extended head posture
  • Sawhorse stance, with the antigravity muscles most affected
  • Retracted lips and ears, tail elevated
  • Excessive muscle tone of the face + jaw clamped
  • Profuse sweating
  • Fever
82
Q

Why do horses die from Tetanus?

A

Death is due to hypoxia and heart failure or respiratory arrest due to paralysis of the diaphragm and intercostal muscles

83
Q

How can Tetanus be diagnosed?

A
  • Clinical signs are typically enough, as well as vaccination history + titre levels
  • C. tetani may be cultured from a wound
84
Q

What is the treatment for Tetanus in the horse?

How can Tetanus be prevented?

A
  • Muscle relaxation: Acepromazine or Diazepam
  • Pack the ears with cotton to dampen noise
  • Surgically debride the wound and flush it
  • Penicillin
  • Antitoxin administration

Prevention:
- Tetanus vaccine

85
Q

What is the causative agent of Botulism?

A

Clostridium botulinum (Usually Type B toxin involved with horses)

The source is usually in hay or silage that has a pH greater than 4.5
or, contaminated commercial grain with a dead carcass

86
Q

What is the pathophysiology of botulism?

A
  • The bacteria is ingested or introduced through a wound and the toxin is released
  • The toxin binds to the pre-synpatic part of the peripheral cholinergic neuromuscular junction
  • The toxin binds irreversibly, leading to the blocked release of Ach
  • This leads to a flaccid paralysis
  • The horse must regenerate new motor endplates, which can take 4-10 days
87
Q

What are the clinical signs associated with Botulism?

A
  • Generalized muscle weakness
  • Dysphagia
  • Colic
  • Decreased eyelid and tail tone
  • Shuffling gait + dragging toes
  • Reduced tongue strength + slow retraction
  • Muscle tremors + recumbency
  • Symmetric and progressive worsening
88
Q

How can Botulism be diagnosed?

A
  • Clinical signs + History
  • Demonstration of the toxin in the wound, GI contents or feed
  • Diagnosis is usually through the exclusion of similar diseases: e.g. Equine Herpesvirus-1, White Muscle Disease, Eclampsia or Equine Degenerative Myeloencephalopathy (EDM)
89
Q

What is the treatment for Botulism?

How can Botulism be prevented in horses?

A
  • Antitoxin administration
  • Supportive: ventilation, IV fluids etc.

Prevention: Vaccination!
Give to the mare 6-8 weeks before foaling to ensure adequate colostrum antibodies

90
Q

What is Stringhalt?

A

Stringhalt is a gait abnormality characterized by exaggerated upward flexion of the hindlimb that occurs at every stride at walk.

The gait abnormality usually lessens at trot and is not evident at canter. It may occur unilaterally or bilaterally

91
Q

What is the cause of Stringhalt?

What is a DDx that presents similarly?

A

The etiology is unknown, but lesions of a peripheral neuropathy have been identified in the sciatic, peroneal, and tibial nerves.
- Possible intoxication causes

DDx: Intermittent upward fixation of the patella, or a painful lesion in the foot

92
Q

What is the treatment of Stringhalt?

A
  • Many of these cases apparently recover spontaneously
  • Large doses of thiamine and phenytoin
  • Severe cases: surgical resection of the lateral digital extensor tendon
93
Q

What is Shivers Disease?

A

Shivers is a gradually progressive, chronic neuromuscular disease in horses that is characterized by difficulty in backing up. Other typical signs include trembling of the tail while held erect, trembling of the thigh muscles and a flexed and trembling hind limb

These horses often move forward just fine with no impact on racing performance

94
Q

What is the cause of Shivers Disease in horses?

A

The ultimate causes of Shivers remain unknown. However, an extensive study published in February of 2015 revealed that the brains of horses with Shivers are damaged in a specific area of the cerebellum, a part of the brain largely devoted to regulating muscular activity

95
Q

What is the treatment for Shivers in horses?

A
  • No specific treatment, but It has been suggested that dietary treatment of affected draft horses with a high-fat, low carbohydrate feed may be beneficial if instituted early in the course of the disease.

Clinical Neurology (17 decks)

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