Term
True or False, Spinal cord neoplasia in horses is most commonly primarily neural in origin |
|
Definition
False,
usually direct extension of primary soft tissue or bone tumors/mets |
|
|
Term
What bacteria is most commonly associated with spinal cord abscesses in foals? |
|
Definition
Rhodococcus equi, abscesses form as an extension of septic process |
|
|
Term
Chronic progressive LMN disease involving sacrococcygeal and cranial nerves in mature horses |
|
Definition
Cauda Equina Neuritis aka polyneuritis equi
paralysis of tail, poor anal tone, bladder atony with overflow incontinance, fecal obstipation)
no tx, mononuclear pleocytosis on CSF (granulometous process) |
|
|
Term
Caudal spinal cord disease, especially prevalant in southern USA and associated with ingestion of sorghum |
|
Definition
Sorghum cystitis and ataxia
symmetrical ataxia and hypoalgesia of pelvic limbs, urinary incontinance |
|
|
Term
Rare disorder associated with short stride and stiff gait when excercising, only pelvic limbs affected |
|
Definition
Aortic iliac thrombosis,
increased oxygen demand during exercise results in ischemic pain in hindquarters |
|
|
Term
What are two parasites that can cause traumatic spinal cord injury in ruminants? |
|
Definition
Hypoderma bovis (cattle) Paralaphostrongylus tenuis (sheep, camelids)
DX both with CSF tap --> eosinophilia |
|
|
Term
What is the most common cause of spinal cord compression in adult cattle? |
|
Definition
lymphosarcoma
progressive paresis, paralysis and ataxia +/- lymphadenopathy(rectal palpation/rads) |
|
|
Term
What is the most common spinal cord disorder in calves? |
|
Definition
Vertebral body abcesses due to hematogenous spread of Actinobacillus pyogens
also traumatic fractures and rickets |
|
|
Term
Asymmetric spasticity of pelvic limbs in calves, normal when recumbent |
|
Definition
Elso heel: spastic paresis
extreme extensor tone when standing, idiopathic - potentially hereditary, permanent tx: tibial nerve neurectomy |
|
|
Term
Intermittent pelvic muscle spasticity in adult cows |
|
Definition
Crampy cow: periodic spasticity
hunched back with legs extended caudally, decreased milk production and progressive weight loss |
|
|
Term
True or False, Clostridium tetani spores are extremely resistant to adverse environmental conditions |
|
Definition
|
|
Term
What neurons are affected by the exotoxin produced by vegetative C. tetani organisms? |
|
Definition
bind irreversibly to inhibitory interneurons (glycine) in the ventral horn of the spinal cord gray matter
--> unimpeded muscle contraction, extensor muscles oppose gravity and tend to be more powerful --> increased extensor tone |
|
|
Term
muscle stifness (esp. jaw), tense facial muscles, prolapsed 3rd eyelide, colic, bloat |
|
Definition
early signs associated with tetanus
|
|
|
Term
What are the later clinical signs associated with tetanus? |
|
Definition
tetanic spasms triggered by noise, opisthotonus, sawhorse stance
NO deffinative diagnosis |
|
|
Term
Horses with marked weight loss despite ravenous appetite, muscle fasiculations, constantly shifting weight from one hind limb to the other, stance with all four limbs close together, managed without access to pasture |
|
Definition
Generalized equine motor neuron disease, associated with chronic vitamin E defficiency |
|
|
Term
What is the diagnostic test of choice to identify equine motor neuron disease? |
|
Definition
biopsy of the sacrocaudalis dorsalis muscle, look for evidence of neurogenic atrophy |
|
|
Term
True or False, botulism in adults is usually caused by ingestion of preformed toxin in the feed |
|
Definition
True,
in foals with gastric ulcers spores may be ingested and toxin produced within the GI tract (aka Shaker foals, extreme muscle weakness results in violent trembling and recumbency) |
|
|
Term
What is the pathogenesis of botulism? |
|
Definition
toxin impairs all peripheral cholinergic neurotransmission, especially at the neuromuscular junction --> results in progressive flacid paralysis of skeletal muscle |
|
|
Term
loss of prehensile ability in lips, decreased tongue tone, may mimic choke, constapation and ileus, flacid tetraparesis death usually from respiratory arrest
|
|
Definition
botulism
No definitive Dx, isolating toxin from the feed is the best chance |
|
|
Term
atrophy of supraspinatus and infraspinatus muscles, abduction of limb during forward motion and lateral deviation of the humerus when walking, little lameness observed |
|
Definition
damage to the suprascapular nerve |
|
|
Term
single limb extensor paralysis with dropped elbow, limb usually carried due to lack of carpal extension |
|
Definition
Damage to the radial nerve |
|
|
Term
Post calving cow with unilateral to bilateral abduction of the hind limb(s) |
|
Definition
obturator (and sciatic ie. peroneal)nerve damage |
|
|
Term
Paralysis of the quadriceps muscle with no weight bearing by the stifle, limb flexed and toe dragged |
|
Definition
damage to the femoral nerve |
|
|
Term
Knuckling over onto the wall of the hoof, inability to extend digit or flex hock, associated with calving/foaling and long periods of recumbency |
|
Definition
|
|
Term
Weak at fetlocks, esp. post calving |
|
Definition
|
|
Term
What are the two most frequently diagnosed conditions associated with acute recumbency and cervical spinal cord disease in horses? |
|
Definition
trauma cervical vertebral malformation |
|
|
Term
short neck, reduced ability to flex the neck, palpable malformations to atlas and axis, variable degrees of tetraparesis and ataxia, especially arabian/saddlebred/appaloosa foals |
|
Definition
occipitoatlantoaxial malformation
DX with rads, no TX |
|
|
Term
Rapidly growing animals, older horses with osteoarthritis of the articular facets, slowly progressive to acute with trauma UMN signs (stiff/spastic) to all limbs, pelvic limbs may be more severely affected, difficulty backing (ie. coordination deficits) |
|
Definition
Cervical vertebral malformation |
|
|
Term
Sagittal diameter corresponds to what anatomic location on a radiograph? |
|
Definition
sagital diameter corresponds to the diameter of the vertebral canal
sagital diameter divided by the width of the vertebral body should be over 50% |
|
|
Term
traumatic spinal cord lesions in horses and foals commonly involve the cervical vertebrae, but foals also commonly have injuries in what other region of the spinal cord? |
|
Definition
thoracic
adults: cervical foals: cervical and thoracic |
|
|
Term
young growing horses without access to grass, potential familial predisposition, lesions may be most prominent mid-thoracic (ie. pelvix limbs more affected) --> symmetric ataxia, paresis, hypometria, poor paniculus |
|
Definition
Equine degenerative myelopathy (EDM)
poor prognosis, vit E supplementation may help and also preventative for horses not displaying clinical signs |
|
|
Term
What are the 5 most common viral diseases of horses that result in diffuse CNS disease? |
|
Definition
EEE, WEE, VEE, WNV, rabies |
|
|
Term
What are the 5 most common viral diseases in cattle that result in diffuse CNS disease? |
|
Definition
Rabies, pseudorabies, IBR, BSE, MCF |
|
|
Term
Unilateral, dropped ear, keratitis, muzzle assymetry |
|
Definition
facial nerve paralysis (CN 7) |
|
|
Term
Head tilt, ataxia, horizontal nystagmus |
|
Definition
|
|
Term
ataxia without weakness, dysmetria, jerky head bobbing and intention tremor |
|
Definition
|
|
Term
What breeds of horses and cattle are predisposed to develop cerebellar abiotrophy? |
|
Definition
Arabian
Jersey, shorthorn, angus, holstein
inherited and associated with BVD infections in utero |
|
|
Term
What disease is associated with: septicemia in neonates dehorning/sinusitis in cattle traumatic skull fractures in horses |
|
Definition
Bacterial meningoencephalitis |
|
|
Term
What organisms are most frequently implicated in association with bacterial meningoencephalitis in horses? In cattle? |
|
Definition
Strep equi in horses actinomyces and fusibacterium in cattle |
|
|
Term
Recently arrived feedlot cattle with diffuse CNS signs, other animals have pneumonia and arthritis |
|
Definition
thrombotic meningoencephalitis (TME)
etiology: histophilus somnus |
|
|
Term
outbreaks of meningitis in young ruminants (more rapid severe clinical course in sheep than cattle), sporatic in adults, diffuse CNS disease, fed poorly cured (pH> 5.6) silage |
|
Definition
Listeriosis (gram +, hardy in environment, intracellular parasite)
ZOONOTIC potential |
|
|
Term
What is the pathogenesis of listeriosis? |
|
Definition
enters through mucosal abrasions--> trigeminal (CN 5) --> forms microabscesses in the brain stem (is. no gross lesions on necropsy) |
|
|
Term
staggering, blindness, rapid death in feedlot sheep |
|
Definition
clostridial enterotoxemia
CNS path: focal symmetrical encephalomalacia |
|
|
Term
What serotype of clostridium is responsible for encephalomalacia in sheep? |
|
Definition
clostridium perfringens type D
Vaccinate! |
|
|
Term
feedlot calves, diarrhea, INTERMITTENT seizure-like CNS signs |
|
Definition
nervous coccidiosis
Tx: amprolium, fluid and electrolytes |
|
|
Term
cattle, muscle twitching--> hyperesthesia and convulsions, low serum Mg |
|
Definition
|
|
Term
sporatic to herd distribution, major management/husbandry changes, young animals, blindness (normal PLR), muscle tremors, incoordination, recumbency with opisthotonos |
|
Definition
|
|
Term
How does a high concentrate ration diet promote the development of polioencephalomalacia in ruminants? |
|
Definition
high concentrate ration helps thiaminase producing bacteria thrive --> thiamine deficiency results in neuronal degeneration and intracellular edema in the cerebrum, additionally the thiaminase bacteria produce hydrogen sulfide gas that can distend the rumen |
|
|
Term
INTERMITTENT CNS signs: ackward stance, licking, head pressing, responds to IV glucose therapy |
|
Definition
|
|
Term
Young growing animals, drought conditions, poor quality feed, blindness, clonic tonic convulsions, progressive paresis/paralysis |
|
Definition
hypovitaminosis A
DX: serum vit A, analysis of feed |
|
|
Term
diffuse CNS signs with concurrent liver disease |
|
Definition
hepatic encephalopathy GRAVE prognosis |
|
|
Term
Non-specific cerebral signs, consumption of mold corn +/- liver enzyme elevations |
|
Definition
fusarium moniliform toxin --> leukoencephalomalacia |
|
|
Term
difficulty prehending food/water, history of ingestion of yellow star thistle |
|
Definition
nigropallidal encephalomalacia |
|
|
Term
True or False, lead poisoning in horses is often associated with a single large ingestion of lead resulting in blindness, ataxia, head pressing and abdominal pain |
|
Definition
FALSE lead poisoning in horses is the result of chronic exposure --> peripheral neuropathies Cattle may present with acute toxicity as described |
|
|
Term
How do organophosphates cause toxicity? |
|
Definition
organophosphates inactivate cholinesterases resulting in overstimulation of paraysmpathetic nerves --> SLUD and miosis |
|
|
Term
dyspnea, diarrhea, miosis, drooling, bloat, collapse, access/exposure to insecticides |
|
Definition
organophosphate toxicitiy
TX: atropine and activated charcol |
|
|
Term
What organisms are responsible for equine protozoal myeloencephalitis (EPM)? |
|
Definition
Sarcocystis neurona and Neospora hughesi |
|
|
Term
True or False, most horses exposed to sarcocystis neurona and/or neospora hughesi develop CNS signs |
|
Definition
FALSE
30-60% of exposed animals seroconvert, of these individuals a few will go on to develop CNS signs (stress is an important predisposing factor) |
|
|
Term
True or False, 80% of cases of equine protozoal myelitis affect the spinal cord only |
|
Definition
TRUE, tends to by ASSYMETRIC and multifocal, ventral horn gray matter --> muscle atrophy |
|
|
Term
What two diagnostics are most informative for equine protozoal myelitis? |
|
Definition
Western Blot (+ indicates exposure) IFAT (+ confirms disease)
both from serum (can also use CSF) |
|
|
Term
TRUE or FALSE, early diagnosis of EPM results in improvement of clinical signs in 75% of horses |
|
Definition
|
|
Term
What's the tx of choice for EPM? |
|
Definition
ponazuril
also NSAIDS, DMSO, Trimethoprim/sulfa (dihydrofolate reductase inhibitors) |
|
|
Term
respiratory disease, abortion, neurologic disease (symmetric pelvic ataxia, urinary bladder paralysis, sporatic in adult horses |
|
Definition
|
|
Term
What is the diagnostic test of choice for equine herpes virus 1 |
|
Definition
throat swab and PCR
also..CSF: high titers, high protein, xanthochromic |
|
|
Term
change in mental status, bizarre behaviors, seizures are neurologic signs that can be localized to ____ |
|
Definition
|
|
Term
inability to coordinate motor movements like eating and drinking is associated with lesions in _____ |
|
Definition
|
|
Term
cranial nerves 3-12 arise from which anatomical region of the brain? |
|
Definition
|
|
Term
loss of consciousness implies damage to ____ |
|
Definition
reticular formation (located in the brain stem) |
|
|
Term
which physical exam test can be performed to assess the integrity of the visual pathway and optic nerve? |
|
Definition
|
|
Term
position of the pupil, size and symmetry of the pupil are all controled by which cranial nerve? |
|
Definition
|
|
Term
the presence of strabismus indicates a lesion affecting which cranial nerve? |
|
Definition
|
|
Term
inability to chew, dropped jaw, loss of sensation to the head indicates a lesion affecting which cranial nerve? |
|
Definition
|
|
Term
dropped ear and corneal ulcers suggest lesions affecting which cranial nerve? |
|
Definition
|
|
Term
paralysis of the pharynx/larynx indicates a lesion affecting which cranial nerves? |
|
Definition
glossopharyngeal (CN 9) Vagus (CN 10) Accessory (CN 11) |
|
|
Term
How can forelimb UMN signs can be exaggerated if subtle? |
|
Definition
forelimb UMN signs are exaggerated when the patient walks up an incline |
|
|
Term
What neurologic abnormality does the tail pull support on physical exam? |
|
Definition
|
|
Term
describe the features of a hypometric gait |
|
Definition
stiff movement with little flexion of the joints |
|
|
Term
describe the features of a hypermetric gait |
|
Definition
increased range of motion, overstepping |
|
|
Term
describe the features of a weak gait |
|
Definition
dragging the limbs, worn hooves, low arc to the swing phase of the stride |
|
|
Term
describe the features of an ataxic gait |
|
Definition
irregularly irregular, poor coordination, swaying from side to side, weaving of the limbs, abducted/adducted foot placement (also can try testing conscious proprioception this way), circumduction when turning |
|
|
Term
Clinical signs associated with spinal cord lesions in C1-C6 |
|
Definition
ataxia, weakness, all four limbs but worse in the rear, hyperactive reflexes |
|
|
Term
Clinical signs associated with spinal cord lesions in C6-T2 |
|
Definition
ataxia, weakness (forelimbs severely affected), depressed forelimb reflexes |
|
|
Term
clinical signs associated with spinal cord lesions affecting T2-L3 |
|
Definition
normal forelimbs, ataxia and weakness in hindlimbs |
|
|
Term
clinical signs associated with spinal cord lesions affecting L4-S2 |
|
Definition
normal forelimbs, ataxia and paresis in the rear limbs |
|
|
Term
clinical signs associated with spinal cord lesions affecting S1-S3 |
|
Definition
distended bladder, dilated anus, loss of tail tone |
|
|
Term
Myelography is useful to diagnose what type of lesion |
|
Definition
compressive (where the flow of dye is disrupted --> dark area on rads = compressive lesion) |
|
|
Term
foals with deranged cerebral function (loss of suckle reflex, hyperesthesia/hyperexcitability, jerky stiff movements, sometimes dyspnea ---> hypothermia, acidosis, seizures, coma) +/- limb weakness, extensor spasms, clonic convulsions |
|
Definition
Neonatal maladjustment syndrome |
|
|
Term
What neuroendocrine factors are implicated in neonatal maladjustment syndrome? |
|
Definition
Allopregnalone (produced by placenta, keeps foals somnolent in utero)
Pregnenalone sulphate (produced by placenta, excitatory effects) |
|
|
Term
What laboratory abnormalities can be seen in foals with neonatal maladjustment syndrome? |
|
Definition
CBC: anemia, inflammation Chemistry: abnormal renal function, liver function, electrolytes Many have normal CSF (can be done to r/o meningitis) |
|
|
Term
An involuntary alteration of motor activity, consciousness and autonomic function caused by a rapid electrical discharge from the cerebral cortex |
|
Definition
|
|
Term
what are some signs associated with partial seizures in large animals? |
|
Definition
jaw chomping, tachypnea, tremor of facial muscles, jerky head movements |
|
|
Term
What is a post-ictal phase? |
|
Definition
period of depression and temporary blindness following a generalized seizure, can last minutes to days |
|
|
Term
True or False, adult horses have a lower seizure threshold than foals |
|
Definition
|
|
Term
What breed is affected by juvenile epilepsy syndrome? What is the prognosis? |
|
Definition
arabian foals, prognosis is good if seizures can be controled, often outgrow the condition between 12 and 18 months of age |
|
|
Term
arabian foals with diluted coat color, difficulty standing following birth, episodes of muscle rigidity in limbs, neck and back --> opisthotonus, paddling +/- nystagmus |
|
Definition
Lavendar foal syndrome (aka coat color dilution lethal), most are euthanized within days of birth |
|
|
Term
What bones are frequently affected in horses with cranial trauma? What neurologic abnormalities may accompany these injuries? |
|
Definition
basisphenoid, occipital, and basioccipital sutures --> dysfunction of vestibulocochlear (CN 8), glossopharyngeal (CN 9), vagus (CN 10), and accessory (CN 11) |
|
|
Term
Signs associated with midbrain hemorrhage |
|
Definition
coma, depression, anisocoria, hemorrhage in inner ear cavities, facial and vestibular nerve abnormalities |
|
|
Term
What CSF abnormalities are supportive of trauma? |
|
Definition
high RBC, high CK, xanthochromia |
|
|
Term
Of the equine viral encephalomyelitides that occur in the USA which has the highest mortality associated with infection? |
|
Definition
EEE (90% mortality) WEE (10-50%) <-- more common in MN
WNV (33%) |
|
|
Term
Warm weather (ie. mosquito season), fever, stiffness, hyperesthesia, muscle fasciculations, head pressing, seizures, anorexia, recumbency.... |
|
Definition
Equine Viral Encephalomyelitides (EEE, WEE, VEE, WNV) |
|
|
Term
What disease must be considered in any large animal with acute ataxia, lameness, mentation changes, or local hyperesthesia of less than 10 days duration? |
|
Definition
Rabies! EXTREMELY variable clinical signs, invariably fatal, ZOONOTIC |
|
|
Term
ruminants closely associated with swine, intense pruritis |
|
Definition
pseudorabies --> non-suppurative encephalomyelitis (no gross lesions, virus isolation and IFA from fresh brain) |
|
|
Term
calves under six months, neurologic and respiratory abnormalities adults may have pruritis |
|
Definition
Infectious bovine rhinotracheitis |
|
|
Term
How is the scrapie prion transmitted between individuals? |
|
Definition
ingestion (placenta), prenatally, direct contact |
|
|
Term
sheep over 18 months of age, pruritis, progressive gait abnormalities, muscle tremors, emaciation |
|
Definition
|
|
Term
What disease are very treatable BUT early diagnosis is essential for good prognosis? |
|
Definition
Polioencephalomalacia, TME, hypomangnesemic tetany |
|
|
Term
What diseases are potentially ZOONOTIC and deffinitive diagnosis is a legal liability/client health concern? |
|
Definition
Rabies Listeriosis toxoplasmosis lead poisoning |
|
|
Term
What diseases are not treatable and must be recognized to avoid unnecessary cost and suffering? |
|
Definition
spinal lymphoma pseudorabies viral encephalitis of the goat |
|
|
Term
What herd health diseases are preventable and deffinative diagnosis allows removal of inciting cause/issue? |
|
Definition
lead poisoning organoposphate toxicity hypovitaminosis A tetanus |
|
|