Musculoskeletal Flashcards
Learning Objective - know and diagnose common toxicants that cause muscle damage
phenoacetic acid herbicides - ataxia/rigid muscles
Ergot Alkalosis
Ionophores
Clostridium
learning objective - know ionophores, the mech of action, and how to diagnose and treat
- Mechanism of Action: inc. intracellular Na, Ca -> mitochondrial swelling and death especially in muscle cells
- Diagnosis: Inc. Muscle enzymes, myoglobinuria
Inc. AST, CK, LDH, ALP, BUN, Bilirubin
Dec. K, Ca (esp. horses) - Treatment: just stop feeding ionophores. supportive care.
- recovered animals may die due to exercise intolerance
_____ are most susceptible to phenoacetic acid herbicides (brand is especially toxic)
dogs (Silvex)
Treatment Phenoacetic acid herbicide toxicity
emesis/lavage
bath
activated charcoal
Ion trapping to enhance secretion
Ergot alkaloids are produce in _____ by Claviceps purprea, similar to alkaloids produced by endophytic fungi in tall fescue. Infected grains have ______.
small grains (barley, rye) black tips
Alkaloids are ____________ agonists which produce hallucinations and leads to decreased prolactin secretion by the pituitary.
Alpha-adrenergic antagonist mechanism -> contraction in uterus and peripheral vasculature, causing _________
dopamine serotonin agonists.
abortion and ischemia
Ergotism treatment
remove source
Mares - metoclopromide and domperidone increase prolactin secretion and normalize gestation
Ionophores are used an an ______ in the beef and dairy industry to prevent coccidiosis and prevent bloat
antibiotic
What species is most susceptible to ionophore toxicity?
least?
(Usually a feed mixing error)
horses
poultry
Clinical Signs of ionophore toxicity 12-72 hours after ingestion
in-coordinated and weak
anorexia, colic, profuse sweating
(cattle similar but with diarrhea and respiratory difficulty)
Tetanus mostly affects _____ via spores in _____.
Toxins block the release of ____ and ____ causing overstimulation of muscle, stiffness and tetany. .
Cattle; puncture wounds.
Clostridium toxin blocks the release of GABA and glycine (which are inhibitory)
unsteady gait with stiff held out tail, twitching and tremors, lockjaw, reluctance to move.
Bloat also common in ruminants.
Tetanus
Clostridium botulinum (tetanus) treatment?
antitoxin only in very early stages, supportive care.
poor prognosis.
Botulism, snake venom, OP insectisides, strychnine are all common toxins for
ventilatory muscle paralysis
respiratory center depressive toxins
barbituates, opiotes
ethylene glycol
hypnotics, sedatives, tricyclic anti-depressants, crude oil