Foal Neuromuscular Disorders

Question 1

What are the various common names given to neonatal encephalopathy?

Answer 1

Dummy Foal Syndrome

Hypoxic/Ischemic Encephalopathy

Question 2

When are clinical signs observed for foal neonatal encephalopathy?

Answer 2

Within the first few days of life

Question 3

What are the suspected pathophysiologic mechanisms for neonatal encephalopathy?

Answer 3

Lack of oxygen/asphyxia
Ischemia-reperfusion injury
Increased excitatory neurotransmitters

Question 4

What are the clinical signs of neonatal encephalopathy?

Answer 4

Poor suckle reflex
Disassociate from mare (dummy foal)
Aimless wandering (wanderer)
Bizarre vocalization (barker)
Seizures
Depression

Question 5

How do we treat Neonatal Encephalopathy?

Answer 5

Supportive care (IV fluids, nutrition, antimicrobials, oxygen therapy)
Anti-convulsants (diazepam, phenobarbital)
Antioxidants (Vitamin E and C, DMSO)

Question 6

What is the prognosis of neonatal encephalopathy?

Answer 6

Good - a large percentage of foals recover with no long term detriments

Question 7

What is the common name for congenital agangliosis?

Answer 7

Lethal White Syndrome

Question 8

Describe the pathogenesis of congenital agangliosis

Answer 8

There is an absense of myenteric and submucosal ganglia formed in the ileum and colon. This leads to a lack of normal progressive motility.

Question 9

What are the clinical signs of lethal white syndrome?

Answer 9

The foals are normal at birth, but develop signs of colic 12-24 hours later.

Question 10

What causes white muscle disease?

Answer 10

White muscle disease is caused by deficiencies in Vitamin E and/or selenium. It may occur due to poor quality hay or soil deficient in selenium.

Question 11

What are the two types of white muscle disease?

Answer 11

Skeletal

Cardiac

Question 12

Why are vitamin-E and selenium physiologically important?

Answer 12

They are important anti-oxidants. Deficiency in them can lead to damage to cell membrane from free radicals.

Question 13

Compare and contrast skeletal and cardiac white muscle disease:

Answer 13

Skeletal - slower onset. Signs include muscle weakness/stiffness, recumbancy, hard/painful musculature, respiratory difficulty, and dysphagia.

Cardiac - sudden onset. May be found dead. Signs include respiratory distress, tachycardia, and recumbancy.

Question 14

How do we treat white muscle disease?

Answer 14

Symptomatic treatment and selenium supplementation.