Bovine Neurological Dzs Flashcards
What are the three causes of polioencephalomalacia?
(1- Ingestion of plants containing thiaminases; 2 - rumen acidosis from eating too much high starch grain with secondary lack of production of thiamine (rare cause); 3 - eating a lot of corn gluten or distillers grain which will contain more that 0.4% sulfur)
What are the main clinical signs of polioencephalomalacia in cattle?
(Blindness, staggering, down, and seizures)
A deficiency in what vitamin reduces the energy available for sodium/water transport mechanisms in the cells of the brain which leads to PEM?
(Thiamine → cofactor for enzymes associated with energy production in the brain)
How does the response to thiamine supplementation for the treatment of PEM differ between if the PEM is non-sulfur or sulfur induced?
(Non-sulfur → up and running around in 15 minutes after giving thiamine versus sulfur induced → you look for 50% improvement in the first 24 hours after starting tx, takes days for 100% improvement and there is a good chance for relapse if thiamine tx is stopped too early)
What is the number one source of lead poisoning in cattle?
(Batteries, have you ever put your tongue on a 9v battery just to feel alive?)
Lead intoxication is acute/chronic (choose).
(Tricky me, cattle may develop signs of lead intoxication from ingestion of a single dose of lead (400-800 mg/kg) or low levels of lead (6 mg/kg) for longer periods of time)
What is the best treatment for lead intoxication?
(Calcium EDTA at various doses → binds lead)
Why is it controversial to treat lead intoxication?
(Hard to establish an appropriate withdrawal time and there is a possibility for future release of lead from the rumen, Dr. Currin usually goes with a 12 month minimum slaughter withdrawal)
Thrombotic meningoencephalitis (TME) is a fulminant neurological disease of cattle caused by what bacteria?
(Histophilus somni)
What is the causative agent of sleeping sickness in cattle?
(Histophilus somni, sleeping sickness is a trade name for thrombotic meningoencephalitis)
What is the antibiotic of choice for treatment of TME?
(Florfenicol → good penetration into brain tissue)
What is the most common way that listeria is obtained in cattle?
(Ingesting poorly ensiled feed → pH > 4.5 or moldy edges)
Listeria unilaterally affects which cranial nerve in cattle?
(The trigeminal nerve)
What are the four things are needed to make appropriately ensiled feed?
(Moisture, anaerobic environment, bacteria, and a substrate for the bacteria to eat (usually starches))
Why should you not allow water deprived cattle to drink as much water as they want?
(Because salt has been packed away into the cell of the brain making them hyperosmolar and when they ingest a bunch of water, that water rushes into the cells and causing them to swell → brain edema, increased ICP, encephalopathy)
