Wooldridge Exam 2

Question 1

Which disease can be prevented by vaccine?

Answer 1

Tetanus, Rabies, WNV, EEE/WEE

Question 2

What is the vertebral formula of the horse

Answer 2

7-18-6-5

Question 3

3 areas for CSF collection

Answer 3

lumbosacral (most common)
atlanto-occipital
C1-C2 (ultrasound guided)

Question 4

What types of changes do you expect to see in CSF with infectious diseases?

Answer 4

pleocytosis
increased protein concentration
maybe xanthochromia

Question 5

Differentials for diseases that cause altered consciousness and cerebellar signs

Answer 5

Degenerative–Cerebellar abiotrophy
Anomalous–Juvenile idiopathic epilepsy
Metabolic– (Hypokalemia, Hypocalcemia, Hepatic encephalopathy)
Inflammatory/Infectious–EEE/WEE/VEE, WNV, Rabies
Toxic–Leucoencephalomalacia
Trauma

Question 6

This disease presents in young arabian foals; they will be ataxic, show hypermetria, spasticity, and intention tremors. but will have NORMAL strength and mentation

Answer 6

Cerebellar abiotrophy

Question 7

Best way to diagnose cerebellar abiotrophy

Answer 7

Genetic test for CA mutation

Question 8

This disease causes seizures in young Egyptian arabians; they can usually outgrow it

Answer 8

Juvenile idiopathic epilepsy

Question 9

Abnormalities in which electrolytes can affect the CNS?

Answer 9

Potassium (hypokalemia)

Calcium (hypocalcemia)

Question 10

This metabolic shift can be seen in neonates/foals that are unable to nurse

Answer 10

Hypoglycemia

Question 11

A horse presents with head pressing and circling; Chemistry panel reveals elevated GGT, Ammonia, and bile acids

Answer 11

Hepatic encephalopathy

Question 12

How are EEE/WEE and WNV transmitted to horses?

Answer 12

Reservoir–birds

Vector–mosquito

Question 13

Is a horse capable of serving as a source of transmission for the viral encephalitides?

Answer 13

No–they are dead-end hosts

horses can RARELY transmit VEE

Question 14

A horse presents with severely depressed mentation, cranial nerve dysfunction, and fever; CSF reveals pleocytosis with lymphocytes…DDX? How would you confirm?

Answer 14

EEE/WEE

Confirm with serum IgM capture ELISA

Question 15

A horse presents with ataxia, depression, cranial nerve dysfunction, and muscle fasiculations; CSF reveals pleocytosis of mononuclear cells and neutrophils…DDX? How would you confirm?

Answer 15

West Nile Virus (WNV)

Confirm with IgM capture ELISA

Question 16

For which disease is a CSF tap contraindicated

Answer 16

Rabies

Question 17

A horse shows depression, colic, and lameness that has rapidly progressed into neurological signs such as ataxia, mania, and hyperasthesia… DDX? How would you confirm?

Answer 17

Rabies

Post-mortem confirmation: Negri bodies & FA test

Question 18

Treatment for EEE/WEE and WNV is mainly

Answer 18

supportive care (NSAIDs, Dex, fluids)

Question 19

Rank WEE, EEE, VEE in terms of mortality (most to least fatal)

Answer 19

EEE (100%)
VEE (60%)
WEE (25)

Question 20

If a horse is _______ its prognosis with WNV is poor

Answer 20

recumbant

Question 21

Which disease is uniformly fatal?

Answer 21

Rabies

Question 22

A horse presents with seizures, mentation changes, and icterus. You find moldy corn in the pasture and/or barn… DDX? How would you confirm?

Answer 22

Leucoencaphalomalacia

Test the feed/moldy corn for Fumonisin B1 toxin

Question 23

Prognosis for a horse Dx with Leucoencaphalomalacia

Answer 23

Grave

Question 24

Which bone is most commonly fractured in the horse skull? What should you NOT use to treat?

Answer 24

Basisphenoid bone; don’t use steroids

Question 25

DDX for spinal cord and vertebral diseases that cause ataxia

Answer 25

Degenerative--Equine degenerative myelencephalopathy (EDM) Anomalous--Cervical vertebral stenosis (Wobbler's) Inflammatory/Infectious-- Equine protozoal myelecephalitis (EPM), Equine herpes myelencephalopathy (EHM) Trauma--to spinal cord/vertebrae

Question 26

A young horse (< 2yrs) presents with symmetric tetraparesis that is worse in the hindlimbs, ataxia, and abnormal limb placement. After ruling out all other causes, you conclude it must be...

Answer 26

Equine degenerative myelencephalopathy (EDM)

Question 27

What are the likely causes of EDM

Answer 27

Vitamin E deficiency early in life | genetic predisposition

Question 28

A young, male thoroughbred presents with acute, symmetrical ataxia (HL more effected than FL), and his neck is painful when manipulated... DDX? What are two methods you can use to confirm?

Answer 28

Cervical vertebral stenosis (Wobbler's) Cervical radiographs; myelogram

Question 29

Which area is usually affected by cervical vertebral stenosis

Answer 29

C3-5 (mid-cervical)

Question 30

A horse presents with asymmetric ataxia and atrophy; the owner believes he has seen opossums on the property recently; a CSF tap reveals antibodies... DDx?

Answer 30

EPM

Question 31

What are the causative agents of EPM?

Answer 31

``` Sarocystis neurona (most common) Neospora hughesi ```

Question 32

Why is the CSF:serum ration important in EPM diagnosis

Answer 32

Helps determine if antibodies are being produced IN the CSF due to active infection or if the Abs are from previous exposure and have crossed the BBB

Question 33

Which test is the best for EPM? Is it definitive?

Answer 33

SAG 2/3/4 ELISA | No, only definitive test is post-mortem

Question 34

Name 3 drugs that can be used to treat EPM

Answer 34

Rebalance (more side effects) Protozil Marquial

Question 35

A horse presents at a show with rapid onset of ataxia and paresis; the HLs are much more effected than the FL and the horse is sitting like a dog and has poor anal tone...DDX? How would you confirm?

Answer 35

Equine herpes myelencephalopathy (EHM) Collect a blood and nasal swab and submit for PCR

Question 36

Which strain of EHV is associated with: 1) neurologic disease 2) abortion

Answer 36

1) D strain | 2) N strain

Question 37

If other horses present with the disease, how would you manage the outbreak?

Answer 37

1) quarantine all affected animals and contact state vet 2) Quarantine 21 days past the time the last horse shows clinical signs 3) vaccinate exposed horses (but not those with signs of disease)

Question 38

What signs would correlate with a traumatic injury to: 1) C1-T2 2) C1-C3 3) C4-T2 4) T2-S2

Answer 38

1) tetraparesis/plegia, recumbancy 2) difficulty lifting head 3) can lift head, but not roll sternally 4) HL and bladder function affected

Question 39

PLR assesses which CNNs?

Answer 39

2--sensory | 3-- motor

Question 40

Which CNN are involved in eye movement?

Answer 40

3, 4, 6, 8

Question 41

Menace assesses which CNNs?

Answer 41

2--sensory | 7--motor

Question 42

Palpebral assesses which CNNs?

Answer 42

5--sensory | 7--motor

Question 43

In horses, ____% of visual input crosses at the chiasm, meaning that the visual deficits are usually on the side ______ to the lesion

Answer 43

80%; opposite

Question 44

Which CNN are important with swallowing/gag reflex?

Answer 44

9, 10, 11

Question 45

Which CNN is associated with tongue tone and movement?

Answer 45

12

Question 46

Concerning the guttural pouch, which nerves are located 1) within the pouch 2) right outside of it

Answer 46

1) 9, 10, 11, 12 | 2) 7, 8

Question 47

What are the main DDx for cranial nerve dysfunctions

Answer 47

Degenerative--Temporohyoid osteoatrhropathy (THO) Inflammatory/Infectious--Guttural pouch disease, Polyneuritis equi Trauma--facial nerve

Question 48

How can you differentiate peripheral and central vestibular disease?

Answer 48

Central--displays proprioceptive deficits

Question 49

What are the predisposing factors for THO?

Answer 49

Trauma | Infection (otitis, guttural pouch, URI)

Question 50

What signs can be expected with THO? (think of nearby structures)

Answer 50

``` vestibular signs (8), facial nerve paralysis (7) difficulty chewing ```

Question 51

Endoscopy on a horse reveals a severely thickened stylohyoid bone, your initial Dx is?

Answer 51

THO

Question 52

Which surgical approach is the best choice when dealing with THO 1) Certaohyoidectomy 2) transection of stylohyoid bone

Answer 52

1

Question 53

A horse presents acutely with hyperesthesia of the perineum; it eventually progresses to tail, anal, and bladder paralysis; you also note CNN deficits and ataxia.. Dx?

Answer 53

Polyneuritis equi

Question 54

A horse presents to you in a strange stance: all 4 limbs are close together and his head is low; the horse is constantly shifting his weight and lying down; when you walk him, his gait is short-strided but he doesn't show signs of ataxia... Dx? what other things could you look for to confirm this?

Answer 54

Equine motor neuron disease Look for black teeth and do a retinal exam for lipofuscin depostion

Question 55

A horse presents in a "sawhorse" stance, his ears are erect, his nostrils are flared, and his signs are aggravated by stimuli... Dx? What organism causes this disease?

Answer 55

Tetanus Clostridium tetani

Question 56

Describe the mechanism of tetanus

Answer 56

it prevents the inhibitory interneurons from releasing glycine-->spastic paralysis

Question 57

When treating tetanus, where are two places to administer the antitoxin?

Answer 57

the wound | intrathecal (into spinal fluid)

Question 58

Tetanus toxid vs. antitoxin?

Answer 58

Toxoid--yearly vaccine | Antitoxin--immediate short acting immunity used for Tx

Question 59

If a horse is wounded and has no history of a tetanus vaccine, what is the protocol?

Answer 59

Administer the toxoid and antitoxin at the same time, but in different spots

Question 60

If a horse is wounded, how long ago should his last tetanus shot have been to avoid re-vaccinating?

Answer 60

< 6 months

Question 61

A horse presents to you as restless, uncoordinated, and with dysphagia. When you perform a grain test, the horse eats extremely slow, and when you pull his tongue from his mouth, he is slow to replace it. Dx? What organism causes this disease?

Answer 61

Botulism Clostridium botulinum (Type B toxin)

Question 62

What are 3 ways a horse can become infected with botulism?

Answer 62

Ingestion (contaminated forage) Wound (rare) Toxicoinfectious (shaker foal syndrome)

Question 63

How does botulism cause clinical signs

Answer 63

prevents ACh release by binding to synaptic vesicles

Question 64

What is the best treatment for botulism and can it be prevented?

Answer 64

Administration of antiserum to neutralize the circulating toxin Yes; type B toxoid vaccine can be used in endemic areas

Question 65

3 characteristics of stereotypic behaviors?

Answer 65

Repetitive Invariant Functionless

Question 66

2 proposed mechanisms for headshaking

Answer 66

``` photophobia trigeminal neuralgia (pain) ```