What You Need to Know About the Rex Guinea Pig

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If you’re looking for an all-around great small pet, let me introduce you to the Rex guinea pig!

With their hedgehog-like appearance and sweet disposition, it’s no wonder why they are becoming one of the most popular guinea pig breeds these days.

Below, we’ll look at everything you need to know to decide if it’s the right breed for your family, from history to personality to healthcare needs.

Let’s dive in!

Rex Guinea Pig Breed History 

Not much is known about the origins of the Rex guinea pig. Due to uncertainty in its gene pool, it is unrecognized as a breed by the American Cavy Breeders Association

It is believed to have come from South America around 1200 to 1532 AD, at a time when people were looking for edible breeds of guinea pig. (Yes, some parts of South America consider them as meat.)

Rex Guinea Pig Breed Characteristics 

The Rex guinea pig shares very similar physical characteristics as the Teddy guinea pig. In fact, it can be quite hard to tell one from the other, especially since both of them share a recessive gene.

Rex Guinea Pig Breed Physical Characteristic 

The Rex guinea pig is reminiscent of a hedgehog when it comes to physical features.

This breed of guinea pig though is easier to handle since instead of spikes, it has a coat making it easier to hold and pet.

As previously mentioned, both Teddy and Rex guinea pigs have a recessive gene that gives them similar kinds of coats.

A Rex guinea pig has a short and coarse coat, just like the Teddy, although the Teddy is known to have a softer coat. 

Although Rex guineas will usually have a straight, wiry coat that sticks out, some of them may have a wavy coat that is different than the common ones you see in this breed.

One other way to distinguish the Rex is to look at the whiskers near the eyes and nose. Rex guineas have more curly whiskers in this area compared to those of the Teddy guineas that have straight whiskers.

The Rex guinea is said to be the largest guinea pig breed among all cavy breeds. Rex cavies can grow up to 18 inches. However, due to size variations, there are Rex cavies that can grow up to only 8 inches in length.

As for color, the Rex guinea pig can come in a huge variety of colors. This may be a result of years of cross-breeding that has led to this wide variety of colors in this breed.

Rex Guinea Pig Breed Personality and Temperament

The Rex guinea pig is also known for its calm temperament and social nature making it a great pet, especially for kids.

The Rex guinea pig is a breed of guinea pig that is a gentle breed. They are pretty calm and, when trained early, are pretty sociable.

This makes them the perfect pet guinea pigs, especially for children and first-time pet owners.

little girl holding a rex guinea pig

Like most guinea pigs, it takes time before a pet Rex will learn to trust you. It is because of this that you must, initially, spend some time with your new pet so that he slowly becomes familiar with you.

In time, it will be comfortable with you and you will be surprised as to how fun and friendly your pet Rex can be.

In fact, they even are known to do some popcorning. (You know..that jumping motion that they do when they are in an extremely good mood!)

Guinea pigs are social animals. Although they are capable of being alone, most of them do appreciate the presence of a constant companion.

Rex guinea pigs can easily get along with other guinea pigs from other breeds, although you may have to get one used to another of the same sex. This is especially true for the adult male guinea pig.

Guinea pigs are intelligent animals too and the Rex guinea pig is no exception.

They can be quite curious and observant. They can also easily learn routines, especially when they start to become familiar with their surroundings.

Guinea pigs are also very expressive and they do try to communicate with their humans when they need to.

You may expect different kinds of noises and sounds from your guinea pig each having a meaning of its own. You may also be surprised that some guinea pigs know how to whistle! 

It is always good for you to be sensitive to your guinea pig’s emotions.

Although the Rex guinea pig does not generally bite, it might give out warning nips to let you know that it isn’t in the mood, or that it feels a bit of discomfort somewhere.

Check out this video to learn the signs that your guinea pig likes you.

Related: All About the Guinea Pig Baldwin

Rex Guinea Pig Care

Caring for this breed of cavy isn’t as difficult as compared to other curly-haired guinea pigs or long-haired guinea pigs.

In fact, this breed can be quite low maintenance making it pretty chill to have them as pets.

This doesn’t mean though that they are zero maintenance as there are still some routines that you have to do on a regular basis in order to keep your pet Rex looking its best.


Unlike long-haired, curly-haired guinea pigs which require daily combing and brushing, the Rex guinea pig, being a short-haired cavy, does not need as much hair maintenance.

Its hair isn’t as prone to matting and knotting, not like the hair of long-haired breeds or curlies, also known as Texel guinea pigs.

That said, it still is recommended that their hair be brushed at least once a week.

It can be a source of bonding between you and your pet Rex, and even be quite relaxing for him once he gets used to it. A soft-haired brush can work best when brushing your pet Rex.

Guinea pigs, too, are generally self-grooming and clean pets. They are quite capable of cleaning themselves up so they rarely need to be given baths.

If, however, they get involved in a really messy situation, you can give them a bath using lukewarm water and guinea pig shampoo while taking extra precautions so that they don’t get stressed out during the routine.

Gently dipping them in lukewarm water will help them relax, especially since guinea pigs aren’t too fond of water in general.

You can take a look at this video to check out how to give your Rex piggy a bath.

One thing to look out for when caring for your pet Rex is its nails.

The nails of a Rex cavy grow faster than other guinea piggies so you most probably need to cut them more often than you would other types of domestic guinea pigs.

You can use a nail clipper or clippers meant for small animals or cats.

When trimming their nails, make sure to avoid the “quick”. This is the blood vessel found from the point of growth of the nail. This is usually pink in color.

Make sure that you hold your piggy gently, but firmly, in order to avoid any injury when trimming their nails.

Nail clipping is a routine that they aren’t too fond of so you will have to be extra patient when handling them every time this time of the month comes.

You can check out this video which demonstrates the proper way of trimming a guinea pig’s nails.

You also have to make sure that you clean the ears of your pet Rex often and check for mites. Ear wax may accumulate in your piggy’s ears or mites might start to lodge in them.

Both of these scenarios don’t bode well for your piggy. You can use a cotton swab to clean their ears, making sure that you don’t insert the swab directly into the ear.

You can put some mineral oil on the swab to help facilitate cleaning.


The diet of Rex guinea pigs is no different from other guinea pig breeds. They require a diet that has high fiber content since this helps in their digestion and it also helps in keeping their gut healthy.

Fibrous food also helps in maintaining their teeth since gnawing onto fiber keeps their teeth stay within normal size. Grass hay, an example of which is Timothy hay, is a great source of fiber for your pet Rex.

Leafy green veggies also fit well into a Rex guinea pig’s diet. An adult guinea pig will need around a cup of veggies each day in order to stay healthy.

Root veggies like carrots and parsnips may be given on occasion although it is best to avoid these since their high starch content can make them easily gain weight.

The same can be said for fruits, which can be considered as sugary foods which serve as treats for your pet guinea.

Guinea pig pellets should also be part of your pet Rex guinea’s staple. They should be getting at least 1/8 cup of these pellets every day.

Bulb foods, such as white potatoes, garlic, and onions, must be avoided at all costs since these can be considered toxic foods your pet Rex.

Dairy products are also not to be given to your pet guinea pig since these may cause stomach upset to your guinea pig. 

One important supplement that must be given to rex cavies is Vitamin C. Guinea pigs, in general, aren’t capable of producing Vit. C.

You can supplement their diet by feeding them veggies rich in Vit. C, such as green peppers, or by adding a few drops of Vitamin C each day to their drinking water.


Being one of the biggest breeds around, it may be best to prepare a cage that will be large enough to accommodate the full size of this piggy.

Remember that your pet Rex grows up to 18 inches so you must prepare a cage that can fit this size of a Rex, just in case you do end up with a large one.

You can actually assemble your own guinea pig cage using corrugated plastic, cable ties, and cube grids which can all be connected using a simple standard connector.

You will need to put some sort of cage bedding inside your guinea pig’s cage.

Aspen shavings, fleece or paper-based bedding are ideal for your pet guinea pig. They absorb odor better and aren’t irritating to your pet guinea’s skin.

Always place your guinea’s cage away from direct sunlight or any extremely hot place as they may succumb to heat exhaustion.

Rex Guinea Pig Breed Health

A healthy pet is the best kind of pet and the Rex guinea is, generally, a strong one.

Unfortunately, like all other living creatures, guinea pigs can get sick and may even have certain health conditions due to an unavoidable gene pool.

A Rex guinea pig that is not in poor health is generally agile and alert.

In fact, it is highly encouraged that you give your pet guinea Rex at least 3 to 4 hours of free, active each day for his overall well-being.

a cute and neat rex guinea pig

Lethargy, in a guinea pig, may be a sign indicating something wrong with its physical health.

Being aware of these signs and symptoms will help you recognize any problem in your pet’s well-being so you can address whatever health issues your pet may have at the earliest possible time.

Health Issues

The most common health problems in all breeds of guinea pigs involve their teeth. Guinea teeth tend to grow long as they age and these may cause problems for them when they eat.

That is why you should always give something for your piggy to gnaw on in order for the teeth to be ground.

Ingrown nails can also be a problem for your pet guinea rex if their names are not clipped on a regular basis.

Watch out for conditions such as diarrhea, coughing (which may be a sign of pneumonia), and eye infections too.

A change in your pet’s appetite may also be a sign of an underlying condition.

If his appetite is not getting any better, it would be best to send him to a vet at the soonest so he can be checked for any health problems.

For more health tips, watch this video:

Life Span

A Rex can live for up to eight years when properly taken care of. Genetic factors may also play a role in determining how long your pet guinea lives.

Without many health problems, you can be assured that your guinea Rex can be with you for a long time.

Where Can I Buy a Rex Guinea Pig? 

Rex guinea pigs can be bought in pet stores, breeders or you can even adopt one.

Be careful though when buying from pet stores or breeders since you can never be assured of the quality of care that these two may provide.

little girl petting Rex guinea pig on top of the table

Always do your due diligence when choosing a pet store or breeder to make sure that you are buying a healthy Rex guinea pig since you’d really want one that will be able to be with you for a long time.

How Much Does a Rex Guinea Pig Cost?

The price of a Rex guinea starts from around $20.

Rex Guinea Pig Breeders in the US

If you want to get your pet Rex guinea from a breeder, make sure that it is a reliable one. It would be better if the breeder is located near or within the area where you live.

Try to go to the location where he keeps his cavies in order to see how they are taken care of. 

You can also check out online reviews and feedback to get a rough idea about his cavies from other customers who may have purchased cavies from him in the past.


What is the difference between Rex and Teddy guinea pigs?

You can tell a Rex and Teddy guinea from each other by checking their whiskers. Rex guinea pigs have curlier whiskers compared to those of the Teddy guinea’s. A Teddy guinea also has softer hair compared to a Rex guinea. The hair of a Rex guinea is more coarse compared to that of the Teddy guinea pig.

How do you groom a Rex guinea pig?

A Rex guinea pig does not require much brushing, unlike long-haired breeds or curly-haired breeds like the Texel. Since they are considered a short-haired breed of cavy, everyday brushing and combing is not a must. Brushing them twice a week is enough to maintain the wavy coat.

Are Rex guinea pigs friendly?

a hand holding a dark brown rex guinea pig

Although it may take time to get your Rex guinea pig accustomed to you, Rex guineas are generally calm and friendly pets. This makes them quite ideal for children and for first-time pet owners.

Are Rex guinea pigs hypoallergenic?

Unfortunately, no. Mammals that have hair or fur, as well as feathers, may always be a cause of allergic reactions in humans.


Rex guinea pigs, just like other guinea pig breeds have a friendly and calm nature that makes them quite ideal household pets.

They also do not require much maintenance since they are clean animals that like to do a lot of self-cleaning as well.

This does not mean, however, that a Rex guinea will not need any tender loving care.

Like all other pets, they will thrive given the proper attention that they need. In return, you can be assured of a loving companion that can be with you for a long time.


  • “Adopt Rex on Petfinder.” 2021. Petfinder. 2021. https://www.petfinder.com/small-furry/rex-51058796/ca/modesto/cali-fid-parrot-exotics-rescue-sanctuary-ca1970/.
  • Dumitru, Sandy. 2021. “ACBA – American Cavy Breeders Association.” Acbaonline.com. 2021. http://www.acbaonline.com/.
  • JohnC. 2018. “Rex Guinea Pig Information, and Hd Pictures, Photos All Details.” Petworlds. March 14, 2018. https://www.petworlds.net/rex-guinea-pig/.
rex guinea pig with a feather on his head

Do you have a Rex guinea pig? What do you like about them? Please share with us below!

Alina Hartley
Alina Hartley

Alina Hartley is a small-town girl with a ginormous love of bearded dragons. It all started with Winchester, a baby bearded who was abandoned at the shelter by his former owners because of a birth defect that caused one front leg to be shorter than the other. Alina originally went to the shelter looking for a guinea pig, but one look at Winchester and it was love at first sight. From that day on, Alina has dedicated her life to learning everything she can about bearded dragons. She loves helping new beardie parents start their incredible journey with these magnificent reptiles.
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