VCA Animal Hospitals

How and Why Cats Purr: Experts Have Theories But Say It's Still a Mystery

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It's no secret that caressing a purring cat is a pleasurable experience — studies suggest it even lowers your blood pressure. But the mechanics of purring itself (to say nothing of the reasons why cats purr in the first place) remains a mystery.

The most common explanation is that a purr originates in the voice box with what are called the "vestibular folds," or false vocal cords. The passing of air across these structures is thought to get the engine running.

Cats purr when they're happy, but cats also purr if they're injured, while giving birth and even when dying. In his masterwork, Catworld: A Feline Encyclopedia (Penguin Reference), British zoologist Desmond Morris has observed that purring is "a sign of friendship — either when (the cat) is contented with a friend or when it is in need of friendship — as with a cat in trouble." If you think about it, a purr is kind of like a smile: Sometimes you smile from happiness, sometimes from nerves.

As with a smile, there's no such thing as a purr that isn't welcome. Cats know this themselves. Kittens start purring even before they open their eyes, rumbling while nursing with what must be a reassuring sound to their mother (who's likely purring herself).

It's pretty special that no big cat can get his motor running the way our household kitties can. Cats purr as effortlessly as breathing, both in and out. In other words, your cat can do something even the biggest, most handsome and imposing Kings of the Jungle can't: Cats purr, lions don't! Sure, tigers can rumble a tiger-sized purr-like sound, but on the exhale only — and really, who wants a tiger sleeping on their bed, anyway?

This article was written by a Veterinarian.


General Practice

We have over 540 animal hospitals in 41 states that are staffed by more than 2,000 fully qualified, dedicated and compassionate veterinarians, with more than 200 being board-certified specialists. The nationwide VCA family of general practice hospitals give your pet the very best in medical care, providing a full range of general medical and surgical services as well as specialized treatments*: Wellness, Spay/neuter, Advanced diagnostic services (MRI/CT Scan), Internal medicine, Oncology, Ophthalmology, Dermatology, Cardiology, Neurology, Boarding, Grooming

*services may vary by location.

Our family of pet hospitals stands out by delivering the greatest resources in order provide the highest quality care available for your pets. By maintaining the highest standards of pet health care available anywhere, we emphasize prevention as well as healing. We provide continuing education programs to our doctors and staff and promote the open exchange of professional knowledge and expertise. And finally, we have established a consistent program of procedures and techniques, proven to be the most effective in keeping pets healthy.

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Specialty Care

Sometimes sick or injured pets need the care of a veterinary medical specialist. When that happens, VCA specialty hospitals work closely with the general practitioner veterinarians who refer cases to us in order to provide seamless veterinary care to your pet. When your pet is facing any kind of serious illness or injury, our specialty referral hospitals will provide the compassionate and expert care your beloved pet needs.

Our goal is to make sure that when you and your pet are in need that you have access to board certified specialists who are up to date on the very latest developments in their field. In our state of the art hospitals, our specialists also have access to the most sophisticated diagnostic and treatment tools and techniques from ultrasonography and endoscopy to CAT scans and even MRI.

We have twenty-eight specialty hospitals across the US so there may be one near you. Our specialized services include: cardiology, critical care, dentistry, dermatology, internal medicine, neurology, oncology, ophthalmology, radiology and surgery.

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Emergency Care

In case of emergency, please call us immediately. If it is after hours, check with a local animal hospital emergency clinic.