Exotic Animal Neurology

Question 1

How reliable are reflex response tests in small mammals?

Answer 1

Not very reliable- because they are prey animals its common for them to freeze up and therefore could be absent

Question 2

What is Encephalitozoon cuniculi?

Answer 2

obligate intracellular fungus that infects rabbits

Question 3

How is Encephalitozoon cuniculi spread?

Answer 3

spores are shed in the urine and ingested or inhaled by other animals
can also spread in utero from mother to foetus

Question 4

What are the common clinical signs of a Encephalitozoon cuniculi infection and why do these signs arise?

Answer 4

head tilt, urinary incontinence and urine scalding
arise because the spore infect cells and cause cell rupture and granulomatous inflammation

Question 5

What clinical sign is specific to rabbit infected with Encephalitozoon cuniculi in utero?

Answer 5

Ocular lesions such as Uveitis and Cataract formation because the fungi causes the lens capsule to rupture

Question 6

How do we diagnose a Encephalitozoon cuniculi infection?

Answer 6

Serological testing- at Day 17 high IgM levels are detectable, then from Day 21-28 IgG levels are detectable
Spore is undetectable before day 17 and is excreted at 3-5 weeks where it cannot be detected

Question 7

In a serology test for Encephalitozoon cuniculi, a negative IgM and positive IgG indicates…

Answer 7

Exposure to Encephalitozoon cuniculi
[remember, a majority of the rabbit population has been exposed so this result is not significant!]

Question 8

In a serology test for Encephalitozoon cuniculi, a positive IgM and positive IgG indicates…

Answer 8

An active infection

Question 9

Which is the only diagnostic method that provides a definitive diagnosis of Encephalitozoon cuniculi?

Answer 9

Post Mortem- changes in brain and kidney as well as PCR testing of tissues

Question 10

How is Encephalitozoon cuniculi treated?

Answer 10

Fenbendazole once daily for 28 days
NSAIDs depending on renal function

Question 11

How can we prevent Encephalitozoon cuniculi infections?

Answer 11

Some recommended preventative Fenbendazole every month but this has little supportive evidence- but always give 28 day course when mixing new rabbits

Question 12

What species differences should we consider when doing an avian neurological exam?

Answer 12

Birds have enhanced vision so can see into the UV spectrum
Iris is comprised of striated muscles so voluntarily controlled- need to use neuromuscular blocking agents to asses them

Question 13

What is the most common cause of acute neurological disease in birds?

Answer 13

Heavy metal toxicosis

Question 14

What can chronic heavy metal toxicosis in birds lead to?

Answer 14

can cause immunosuppression leading to secondary infections

Question 15

How do we diagnose Heavy Metal Toxicosis?

Answer 15

Radiographs to look for metal foreign bodies
Blood tests to assess metal levels in the blood (only for lead and zinc)

Question 16

What medication is used to treat Heavy Metal Toxicosis?

Answer 16

Chelation (bonding of ions) using Calcium Edetate or Penicillamine
Supportive care

Question 17

How do we treat Heavy Metal Toxicosis (apart from medications)?

Answer 17

Psyllium treatment (high fibre diet to flush and pass toxin)
Gizzard Flush
Ventriculotomy (cut into ventricles to remove particles manually)

Question 18

What does Avian Bornavirus cause?

Answer 18

Can cause up to 15 different disease processes including-
Avian Ganglioneuritis
PDD (Proventricular dilation disease)
Encephalomyelitis
Lymphoplasmacytic Ganglioneuritis

Question 19

What are some clinical signs of Avian Ganglioneuritis?

Answer 19

weight loss, regurgitation, delayed crop emptying and undigested seed in faeces, ataxia, head shaking and cortical blindness

Question 20

How is Avian Bornavirus diagnosed?

Answer 20

Radiography to view inflammation and dilation of proventriculas (this is better seen using Barium series)
PCR/ Serology

Question 21

How is Avian Bornavirus disease treated?

Answer 21

Palliative care with pure COX2 NSAID to reduce inflammation such as Celecoxib or Meloxicam

Question 22

What do we need to consider for efficient reptile neuro exams?

Answer 22

Iris contains some skeletal muscle so voluntary control of eyes
Ectothermic so neuro exam should be performed at the preferred optimal temperature zone

Question 23

What is the most likely diagnosis for a bearded dragon with neurological and gastrointestinal disease?
How can we confirm our suspicions?

Answer 23

Adenovirus- confirm with a PCR or an oral or cloacal swab