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Rex Guinea Pig Info: Pictures, Personality & Traits

rex guinea pig

Weight: 700-1200 grams
Lifespan: 5-8 years
Colors: Patterned and solid variations of brown and white
Temperament: Friendly, gentle, and calm

The Rex Guinea Pig is a common and well-loved guinea breed. It has a short and wavy coat that gives it a hedgehog-like appearance. Rex guineas are calm and gentle and loved to be handled and petted. This makes them a perfect pet for responsible children. Their short and stubble-like coat stands up like a hedgehog and helps protect them from water. The coat can vary, however, and some Rex guineas have slightly longer, wavier coats. Their short hair makes them a low-maintenance breed of guinea, and they don’t require daily grooming and bathing.

They commonly grow between 20 and 40cm in length and can live up to seven years old. They have big, droopy ears that hang down onto their thick woolen fur, giving them a cute and friendly appearance. They are a great guinea for a child or a first-time owner, as they are easy to look after and require minimal specialized maintenance.

3 Little-Known Facts About Rex Guinea Pigs

1. Their toenails grow extremely quickly

A Rex guinea doesn’t need much maintenance in the way of grooming or brushing, but its toenails grow much quicker than most other breeds. This means they will need to be clipped fairly regularly to prevent ingrown nails, which can quickly become infected.

2. They have a recessive gene

A Rex guinea’s short hair is caused by a unique recessive gene that makes their fur short and coarse.

3. Rex guineas look like Teddy guineas

Nobody knows where the Rex guinea originates from, and they are almost indistinguishable from “teddy” guineas, as they both have this unique recessive gene. One clue to tell them apart is that the Rex tends to have curlier whiskers at the eyes and nose.

rex guinea pig
Image: Pixabay

Things to Know When Owning a Rex Guinea Pig

Food & Diet Requirements🥕

Rex guineas are hardy and don’t have any specialized dietary requirements. An important consideration is that guineas cannot make their own vitamin C, so they need to be given it as a regular part of their diet, preferably daily. Good-quality pellets are the best food for all guineas, as they contain all the nutrients, vitamins, and fiber requirements needed for a complete diet. Occasional vegetables and leafy greens are also a great addition to a guinea’s diet. Fresh fruits are high in sugar, though, which is not good for guineas in large amounts, and so should be given sparingly.

You should avoid commercial foods that contain artificial flavorings and colorants or seeds and nuts as a daily staple — these should only be given as occasional treats. Although commercial pellets will likely include high-fiber hay in the ingredients, fresh timothy hay should be on hand for your guineas at all times. Be sure that this hay is fresh and not chemically treated.

All guineas should have constant access to clean, fresh water, provided ideally by a drip bottle system to keep the cage dry and the water clean, and the water should be changed daily.

agitated rex guinea pig
Image Credit: PHOTO FUN, Shutterstock


No matter the breed of guinea pig, regular exercise is an important factor, and they should be provided with an enclosure big enough to run around in. Rex guineas are social and playful and are best kept in pairs or more. Bear in mind that while other small rodents will benefit from an exercise wheel, it can cause harm to a guinea’s back and should be avoided.

Grooming ✂️

A Rex guinea’s short and coarse hair is extremely hardy and won’t need a huge amount of maintenance. That said, it’s recommended to give them a good brushing occasionally and a bath a few times a year. As mentioned, a Rex guinea’s nails tend to grow quickly, far quicker than most other breeds of guineas. This means they will need regular maintenance and clipping, or they may become ingrown and cause infection.

Health and Conditions 🏥

Serious Conditions:

Even though Rex guineas are a tough and hardy breed, they are still susceptible to serious health issues. If their fast-growing nails are not kept regularly clipped, they can become ingrown and potentially cause infections and walking issues. Too much fruit or vegetables can cause obesity and diabetes in your guineas and can easily be fatal. Too much wet and sugary foods can also cause diarrhea, which can quickly lead to dehydration.

Minor Conditions:

A guinea that does not have sufficient vitamin C in its diet can suffer from vitamin C deficiency, which can lead to an unhealthy coat that could eventually result in hair loss and a compromised immune system. If a guinea doesn’t have access to fresh hay, they can quickly develop digestion and teeth issues.



Rex Guinea pigs are highly social and gentle, love to be petted, and have a great personality. They are curious and friendly, making them perfect pets for children. Their active nature means they need a large amount of room in their cage to run around in and play, and they love interaction with humans.

Rex guineas are low maintenance, making them an ideal choice for first-time guinea owners.

For more about Guinea pig breeds check out these posts:

Featured Image: Pixabay

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