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Barks & Mewsings

The Trupanion blog

Why Does My Cat Have a Saggy Belly? Understanding the Feline Primordial Pouch

By: Brianna Gunter

A cat stands in a meadow with his primordial pouch visible

Cats are majestic creatures known for being agile and sleek. But wait, what’s that swaying beneath kitty as he moves? Why does my cat have a saggy belly?

Don’t worry—your feline friend doesn’t need a tummy tuck. Cat bellies have a natural flap-like appearance called a “primordial pouch,” and it is rarely cause for concern. Read on to learn more about cat primordial pouches and what all pet owners should know about them.

What is a cat primordial pouch?

The primordial pouch, or belly flap, is a long stretch of skin that runs the length of your cat’s tummy, but it most pronounced towards the rear. Instead of being closely attached to the muscle like the rest of your cat’s skin, this flap is loose and naturally only has a thin layer of fat. As a result, it may swing freely from side to side while your kitty runs, or it may appear to hang by his legs when sitting.

Fascinatingly, animal experts aren’t quite sure why cats have these belly flaps. As José Arce of the American Veterinary Medical Association told Live Science in 2021, there are three main theories:

  • Energy storage—the pouch allows cats to store excess fat that they will later burn off. This is important for cats in the wild who don’t have the ready access to food that domestic cats do.
  • Protection—having a little excess skin and layer of fat offers cats more padding in one of their most vulnerable areas.
  • Movement—the stretchy belly flap may allow cats to move more easily, especially when jumping and performing other acrobatics felines are known for.

Understanding fat vs. primordial pouch

Many pet owners notice their furry friend’s low-hanging stomach and think their cat is getting fat, but that’s often not the case. Still, it can sometimes be difficult to tell.

To determine if the area is fat or flap, start by looking at how it moves. Fat cat bellies tend to swing less as a result of greater density, while a normal primordial pouch will be more loose and free. A pouch will also have an appearance closer to that of a deflated ball, while fat will look fuller.

You can also use your hands to gently feel for your cat’s ribs. If they are difficult to feel or you can’t find them at all, it’s a sign that your kitty is overweight. Likewise, cats carrying extra weight will be more rounded in appearance, while a regular weight cat will appear slim and straight down the sides no matter how prominent their primordial pouch is.

If you’re concerned your pet may be overweight, consult with your veterinarian. Just like in humans, excess weight in cats can put them at greater risk of health conditions like diabetes, arthritis, hypertension, and even certain types of cancer.

Do all cats have a primordial pouch?

A fluffy tri-colored cat lays with its belly exposed on a chair

All cats have primordial pouches as part of their species’ genetic makeup, though some are barely detectable while others are obvious. Because of this, there is a common misconception that hanging bellies are a common trait that doesn’t occur in all cats.

Nevertheless, what has been found is that the pouch appears more visible in certain cat breeds. Males may also be more likely to have a prominent primordial pouch compared to their female counterparts (but more research is needed in this area). Even underweight cats may still have a clearly visible pouch hanging down.

In addition to your pet pal, these belly flaps can be spotted on big cats like tigers and lions. It’s your kitty’s connection to the wild!

Cat breeds with more pronounced pouches

Genes appear to play a big role in how prominent cat belly flaps are. Domestic feline breeds that tend to have more pronounced ones include:

  • Bengal
  • Egyptian mau
  • Maine coon
  • Ragdoll

How age affects your cat’s belly appearance

Cat primordial pouches may first become noticeable around six months of age. Because this coincides with when many pet owners have their cats spayed or neutered, another misconception is that the belly flap is a side effect. “Spay sway” has become another term for this loose skin as a result, though it remains inaccurate.

Your cat’s primordial pouch may sag further as he reaches older age and become more pronounced as a result. There is no need to be alarmed by this, but if you are concerned, give your veterinarian a call.

When to talk with your veterinarian

A primordial pouch is a normal part of a cat’s body. That said, if you notice that it seems to be bothering your cat or hindering her mobility, make an appointment with your veterinarian. Sudden changes in size or texture are also calls for concern.

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We’re the official blog of Trupanion—chosen by veterinarians as the #1 pet insurance in America. Here you’ll find useful dog and cat care tips, interesting veterinary insights, and fun pet topics galore.

While you’re browsing our pet blog, please note that the views expressed here are those of the individual authors and do not necessarily reflect those of Trupanion. Our articles are reviewed by veterinarians for accuracy, but they are not a substitute for professional diagnosis and treatment. Always consult with your own pet’s veterinarian for advice.

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