Central Nervous System

Question 1

For listeriosis in cattle:

1. Name the cause of the condition that is most commonly implicated
2. What food is it typically found in?
3. How is it diagnosed?/What are the clinical signs?
4. What is the prognosis for the condition?
5. What are the best treatment options?

Answer 1

1. Listeria monocytogenes
2. Seen in poorly fermented silage
3. Mononuclear pleocytosis (bacteria are very hard to grow) - cranial nerve defects (asymmetrical)
4. Good prognosis if treated early
5. Amoxicillin, procaine, oxytetracycline + correct acid base derangement’s

Question 2

For cerebrocortical necrosis (Polioencephalomalacia):

1. How is a diagnosis typically made?
2. What is the pathophysiology typically involved in the condition?
3. The CSF signs resemble what other disease?

Answer 2

1. Histologic diagnosis
2. Altered thiamine metabolism - required for the pentose phosphate pathway (PPP) - main method of producing glucose in the brain
3. CSF signs - identical to those with listeriosis

Question 3

What are four potential cause of cerebrocortical necrosis?

Answer 3

Any of the following:

1. Lead poisoning
2. Lactic acidosis (Grain overload)
3. Salt intoxication/water deprivation
4. Bracken fern toxicity
5. Sulfur intoxication
6. Amprolium intoxication