What Is a Primordial Pouch? Surprising Facts About Your Cat’s Saggy Belly

Last Updated on: October 12, 2023 by Crystal Uys

Is there anything quite as adorable as when your cat runs to you with his big belly swinging? A cat’s belly flap is officially known as the primordial pouch, and, as cute as it is, it serves a bigger purpose than you might think. Read on to learn more about your cat’s primordial pouch, including tips on how to tell if your cat is just really big or if he’s actually overweight.

What Are Primordial Pouches?

Primordial pouches are sacs of excess skin and tissue that run the length of the cat’s underside. It’s found most prominently towards the rear portion of the tummy. Every cat will have one, but the size of each will vary from cat to cat. Some kitties will have an almost entirely undetectable pouch, while others will have larger, prominent ones.

Did you know primordial pouches aren’t unique to our household cats? Big cats like lions and tigers have them, too!

When Do Cats Develop a Primordial Pouch?

If you’ve had your cat since kittenhood, you may have noticed that he didn’t have the pouch when he was young. That’s because cats don’t develop the primordial pouch until they’re around six months old.

What Purpose Does the Primordial Pouch Serve?

While the exact purpose isn’t entirely known, three primary theories exist as to why cats have them.

Protection

One of the most universally recognized theories for the primordial pouch is that it acts as protection. Cats in the wild may attach one another in the belly region, so the fat pouch serves as protection for their internal organs. Even if your kitty is an indoor cat, it can still get into fights with other pets in the home, which could be why the primordial pouch has evolved away.

Flexibility

Another common theory is that the pouch provides cats with better flexibility through their abdomen. A cat’s powerful hind legs, paired with the excess belly skin, allow them to twist and leap high into the air, providing more flexibility for escaping predators and participating in high-octane zoomie sessions.

Food Storage

A cat’s primordial pouch can provide space for their abdomen to expand for food storage purposes. Think of their pouch as your pair of comfy pants you put on after Thanksgiving dinner to give your belly more space to expand when you’ve eaten far too much.

Additionally, it is theorized that the pouch can act as a fat reserve, storing the fat that cats can later use for energy if they do not have access to reliable food sources.

Why Are Some Pouches Bigger Than Others?

Several factors can influence the size of your cat’s primordial pouch.

• Genes: Some cats may have larger or smaller primordial pouches based on their genetics. Certain breeds are genetically predisposed for larger pouches (we’re looking at you, Bengals and Japanese Bobtails!).
• Weight: Cats, just like humans, carry weight differently. A cat’s weight distribution can affect how big their pouch will look. Fun fact—if your kitty’s pouchy looks huge, it might actually be an indicator that he is in fantastic shape. Overweight cats have larger midsections which can obscure the pouch, while a cat at a healthier weight may have a pouch appearing more prominent compared to the rest of his body.
• Age: As with humans, cats lose muscle mass and skin elasticity as they age, causing the pouch to hang lower than usual.
• Pregnancy: A pregnant cat’s pouch may hang lower than usual to accommodate her growing kittens.

Primordial Pouches vs Fat Pouches

Cat owners must be able to differentiate between primordial pouches and fat pouches caused by obesity. As in humans, excess weight can cause health conditions like diabetes and heart problems in cats.

The easiest way to know if your cat is obese is by looking at his shape. Cats with excess weight have rounder bodies than their healthy weighted counterparts. Stand above your cat and look down at his standing body. You should be able to see a slight indent at his hips. If his waist bulges instead of indents, he may have more body fat than necessary.

You can also do a touch test by feeling your cat’s rib cage. A healthy cat’s padding will be around as thick as the back of a human hand. If you’re unable to feel your cat’s ribs or can only feel them if you apply firm pressure, your kitty could be overweight.

Your veterinarian can also weigh in (pun intended) on your cat’s weight at your next annual check-up. If they deem your kitty to be a little heavy, they can provide a plan of action to help you help him achieve a healthier weight.

Should I Ever Be Worried About My Cat’s Primordial Pouch?

Every cat has a primordial pouch, so you shouldn’t fret too much about your pet’s low-hanging belly. However, the abdomen can be a great indicator of health issues, so keeping a close eye on your kitty’s belly doesn’t hurt. For example, female cats can develop breast cancer that presents as lumps in the tummy area. The more familiar you are with what is normal for your cat and his abdomen, the easier it’ll be for you to detect any concerning changes.

Final Thoughts

A cat’s primordial pouch is just one of our feline family members’ many adorable features. As cute as they look, swaying back and forth as your cat moves about your house, the pouches serve an important purpose going beyond aesthetics. Know that it’s totally normal for cats to have these pouches and for them to jiggle a little more with every passing year.

If you think your cat’s primordial pouch is getting bigger than it should be, or if you’re unable to tell if your cat is overweight or just the owner of a large pouch, contact your vet. They’ll do a physical examination to check your cat’s overall health and can provide some tips on keeping your cat at a healthy weight if they deem his weight to be a problem.

Featured Image Credit: Phrakrit Juntawong, Shutterstock

About the author

Cat mom to Ivy – a feisty little rescue kitten that is her one and only child. For now! Throughout her life, she has been introduced to the special love that can be found in the bond with a cat. Having owned multiple felines, she is more than certain that their love is unmatched, unconditional and unlike any other. With a passion to educate the public about everything, there is to know about felines, their behavior, and their unique personalities, Crystal is devoted to making sure that all cats and their owners know the importance of conscious living – and loving!