Final Flashcards
What is equine leukoencephalomalacia?
It is a condition caused by fumonisins, a mycotoxin produced from moldy corn
What is the main adverse affect of fumonisins?
They are hepatotoxic
What are the clinical signs of equine leukoencephalomalacia?
- Blindness
- Head pressing
- Aimless walking
- Stupor
- Glossopharyngeal paralysis
- Delirium
- Recumbency
- Seizures
- Death
Fumonisins cause ______ morbidity and _______ mortality in ________.
Low
High
Horses
What are the lesions that equine leukoencephalomalacia cause?
Subcortical white matter necrosis- can be bilateral or unilateral
What toxins can cause blindness in animals?
- Lead-Cattle
- Ivermectin
- Pyrethrins-Dogs/cats
- Metaldehyde-
- Fumonisin
- Salt
What substrate will grow fumonisin?
Corn
Why is fumonisin a public health concern? Aflatoxin?
It can cause esophageal cancer in humans
Alflatoxin is carcinogenic
How would you confirm a case of equine lueikoenceaphcalomalacia from fumonisin?
Screen corn by analyzing representative samples
What nicotinic products are the most hazardous and why?
Liquid cartridges and refills for e-cigarettes as they have concentrated levels of up to 2,000mg
What are the clinical signs of a nicotine toxicity?
- Vomiting
- Hyperactivity
- Tremors
- Seizures
- Respiratory paralysis leading to death
How long is the nicotine half life?
Short
How do you diagnose a nicotine toxicity?
Nicotine residues
What is the treatment for nicotine toxicity?
It is patient dependent, but should decontaminate with lavage/AC, control the CNS excitation and give oxygen support.
Which receptors does nicotine bind to?
Nicotinic acetylcholine receptors in the parasymphathetic and sympathetic nervous system
Which genetic issue is involved with ivermectin?
MDR1 (ABCB1) mutation in some dogs
Which species should you never use ivermectin in?
Turtle
What is the MOA of the MDR1 (ABCB1) mutation?
P-glycoprotein isn’t produced, so drugs can’t get pumped out of the blood brain barrier and end up staying in the CNS. In addition, the drug accumulates in the bile and kidney instead of being secreted.
If a dog has a MDR-1 mutation, what do you need to be aware of?
They can have multiple drug resistance, not just to ivermectin.
The half life of ivermectin varies in length due to three factors, what are these?
- Sensitive/non-sensitive patient
2. Hezterozygote or homozygote
What is the mechanism of action of ivermectin?
It targets the GABA and glutamate-gated chloride channels releasing inhibitory neurotransmitters.
What are the clinical signs of an ivermectin toxicity?
- Depression
- Lethargy/weakness/recumbency
- Tremors (high dose)
- Seizures (high dose)
- Reversible blindness
- Coma leading to death
How long can the clinical signs last with ivermectin toxicity?
Hours, days to weeks as it is hard to predict
A client tells you that she gives her horses oral ivermectin twice a year and now her dog is showing signs of depression, lethargy, recumbency and blindness. What may be going on?
Ivermectin toxicity