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Black Widow Spider Bites in Cats

Black widow spider bites can be dangerous for cats.

Most people know about black widow spiders and can identify their classic red hourglass marking.

Cats can be bitten by black widows, too. Here's what you need to know about black widow spider bites in cats.

Black Widow Spiders Don't Bite Often, but Cats Are at High Risk

Researchers have proven that black widow spiders are picky about when they bite and when they deliver venom (David R. Nelsen, 2014). The shy spiders will usually try running away or playing dead first when antagonized. They will also sometimes flick silk at an intruder or bite without releasing venom. They can even choose how much venom to release during a bite, which they seem to decide on based on the threat level.

All of this is good news for humans because it means they're not too likely to be envenomed by a black widow spider and, if they are, it is usually not a fatal amount for an adult human.

However, cats are adept at finding the hiding spots of these elusive spiders and antagonizing them to the point of being bitten and injected with venom. They don't know the danger these spiders hold for them, and they are predators that love to give chase. And a cat's small size means that even a little venom can be deadly.

How Does Black Widow Venom Work?

Black widow venom contains latrotoxins, which are neurotoxins that attack the victim's nervous system. The bite causes severe pain, and signs include paralysis, muscle cramping, tremors, drooling, difficulty breathing due to paralysis of the abdominal muscles, increased blood pressure, falling over, vomiting, and diarrhea.

Because cats are small and particularly threatening to spiders, they are at risk of dying from black widow spider venom.

Treatment for Black Widow Spider Bites in Cats

If you know your cat was bitten by a black widow spider or suspect it, it is an emergency situation. Your cat needs to be taken to a veterinary hospital immediately, where they may need to provide oxygen treatment, intravenous fluid therapy, muscle relaxants, pain killers, anti-seizure medications, and anti-venom.

Works Cited

  1. David R. Nelsen, W. K. (2014, March). Poke but don't pinch: risk assessment and venom metering in the western black widow spider, Latrodectus hesperus. Retrieved from DOI: 10.1016/j.anbehav.2013.12.019.

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