venomous and poisonous animals Flashcards
toxin vs venom vs poison
- Toxin: biological origin
- Venom: the toxin is injected into the animal with a specialized
venom apparatus - Poison: the toxin is delivered to the animal passively, through
dermal or oral exposure
what is this, target, toxin, species
black widow spider
Toxin: α-latrotoxin
- Targets: CNS, PNS, neuromuscular junction
- Toxicity: single bite can be fatal
- Cats, horses are very sensitive
black widow spider clinical
-painful bite onset 8 hr
Progressive onset of extreme pain**
* Loud vocalization, howling in cats
* Hypersalivation, restlessness
* Muscle cramping
-Muscle tremors and rigidity progresses to flaccid paralysis over several hours**
- Death due to respiratory or cardiovascular collapse
- Long-term: weakness, lethargy, muscle pain
black widow spider management and diagnosis
- Management:
- Antivenin if available**
- Symptomatic and supportive car
- Diagnosis: clinical signs, identification of spider in
vomitus (small animals)
what is this? target,
brown recluse spider
* Loxosceles reclusa
Toxicity: single bite
* Target: skin*, RBC
brown recluse spider clinical signs
- Non-painful bite**
- Within 3-8 hours: pruritus, pain, swelling, target lesion** ± central vesicle that blackens over time
- Tissue can slough within 2-5 weeks → massive indolent ulcer
- Systemic signs within 72 hours: fever, vomiting, tachycardia, dyspnea, renal failure, coma
- Hemolytic anemia with hemoglobinuria
brown recluse management and diagnosis
Management:
* No specific antidote or antivenin
* Symptomatic and supportive care: analgesics, antibiotics, IVFT
* Open wound management – do not surgically remove**
diagnosis: hard, no test
tick bite paralysis species, target, mechanism
most common dogs
- Target: CNS
- Mechanism of action: inhibition of acetylcholine release at
neuromuscular junction and autonomic ganglia →
neuromuscular blockade - Flaccid paralysis**
ticks that can cause tick paralysis
-Tick species in North America: Dermacentor andersoni
(Rocky Mountain wood tick) , D. variabilis (American dog
tick), Amblyomma americanum (Lonestar tick)
tick bite paralysis clinical
onset: 72 hours to 1 week
- Rapidly progressive neurologic signs
- Early: loss of appetite, loss of bark, ataxia
Ascending symmetrical LMN paralysis**
* Pelvic limbs → thoracic limbs
* Decreased to absent spinal reflexes
* Cranial nerve signs
* Tetraplegia, respiratory paralysis, death
tick bite paralysis diagnosis and management , ddx
Management: remove the tick
* Clip hair to look for other ticks, supportive care
Prevention of tick bites: oral tick preventative
DDx: botulism, Coonhound paralysis
crotalid snakes / pit vipers clinical
-Rattlesnakes, copperheads, cottonmouths
-Vast majority of bites in North America**
- Onset: peracute
- Severe local tissue damage**
- Swelling, bleeding, ecchymosis, pain
-mycotoxicity releases myoglobin
-blood: hemolysis, vascular damage DIC
pit viper bite management / diagnosis
Bite location – neck vs. leg vs. body
* Antivenom within first 6 hours most effective**
* Anaphylaxis possible
* Symptomatic and supportive care
- Diagnosis: snake bite witnessed or evidence of snake bite, supportive bloodwork findings
prognosis: depends on response to antivenom** can cause anaphylaxis, vommiting, $$$
elapid snake envenomation, target and clinical
- Coral snake: only elapid snake in North America**
- Target: CNS
clinical:
* Scratch like bites with minimal pain and no swelling**
* Onset: variable → can be acute or delayed up to 12 hours
* Vomiting, hypersalivation
- Sudden onset of lower motor neuron signs**
- Ataxia
- Hyporeflexia or absent reflexes
- Paresis progressing to quadriplegia
- Hypoventilation: tachypnea, abdominal breathing
- Death due to respiratory failure
elapid snake envenomation management and diagnosis
Antivenin**$$
-supportive care
prognosis good with antivenin
blister beetle poisoning species sensitivity, substrate, clinical signs, and management
-species: horses»_space; cattle
-alfalfa
toxin: cantharidin
clinical signs: colic, mucosal damage
erosions, ulcers.
management: decontamination, supportive care, remove feed. gastroprotectants, management of shock
