Do Guinea Pigs Change Colors Over Time? A Deep Dive

One more unusual and interesting fact about guinea pigs is that they can change color. It doesn’t happen overnight, so you don’t have to worry that your beloved chocolate piggy will suddenly morph into a white snowball. There are several reasons why a cavy’s color may change, and although it can be unexpected, it is perfectly normal.

Guinea pigs can change color in response to seasonal changes or genetics. They often change shades after their first shed at around three months. Some piggies carry roan or grizzling genes, which affect coat color. Himalayan and Californian cavies are born white and develop dark points.

Many owners notice subtle color changes in their pet’s coat and become concerned that they are sick or aging prematurely. Let’s explore why guinea pig fur may change color and when you should be concerned.

Can Guinea Pigs Change Colors?

When you first notice that your guinea pig is changing color, you may think it’s your imagination. It can be surprising to scroll through your photo gallery and realize that your pet really has changed shades.

The first and most dramatic color change often happens when baby piggies shed their first coat and grow adult fur. In addition to being thicker and coarser, the shade can differ significantly from its original baby coat.

Guinea pigs shed and regrow in the same way as many other domestic pets, like cats and dogs. Each time they lose hair, it is replaced with new hair, usually a thinner summer coat and a thicker covering at the start of winter.

New hair that grows to replace shed fur may be lighter or darker than the previous shade in response to seasonal changes. Cavy fur may also fade if exposed to a lot of direct sunlight, and this will be particularly evident if your piggy cage is in a spot where it gets a lot of natural light.

Factors affecting a guinea pig’s color include:

  • Genetics – Some animals are preprogrammed to become lighter, darker, or fade out over time.
  • Diet – Nutritional deficiencies can result in a lackluster, dull coat.
  • Age – Although guinea pigs don’t become grey like humans, they may become darker or lighter with age. The most significant age-related color change occurs after they shed their baby coat.
  • Environment – Factors like the amount of direct sunlight the guinea pig receives and ambient temperature can result in a darker or lighter coat color.

Himalayan and Californian guinea pigs only develop colored points when they get older. These cuties start off solid white and slowly transform into ‘the Siamese cats of the guinea pig world.’ Their coats are highly susceptible to color changes based on the climate. Their coats become darker in cold temperatures, and their dark spots can fade if exposed to too much direct sunlight.

Why Do Guinea Pigs Change Colors?

It is natural for a guinea pig’s color to vary somewhat during its life. Each time the animal sheds, it may develop a slightly darker or lighter coat in response to the changing season or ambient temperature.

Genetics also plays a role in determining guinea pig colors. Some animals carry a grizzling gene and will produce silver strands among the solid colors on their body. Others have a roan gene, which is more evident in white guinea pigs as they develop patches of color where they were solid white before.

Although piggies don’t typically go grey from old age like humans, they can develop some age-associated grey fur around the nose and mouth. While the overall color of cavies may fade a bit as they get older, with regular grooming and a good diet, their fur can remain in lustrous condition at any age.

Why Is My Guinea Pig Turning Grey?

The average life expectancy of pet guinea pigs is between five and seven years, so it can be scary for owners to discover that their two-year-old is developing grey hairs. Fortunately, silver or grey strands between the colored fur on a piggy’s body are not signs of premature aging but rather that the animal has inherited the grizzling gene.

Because guinea pigs have been used as laboratory animals for so long, their coat colors and how they change have been carefully studied and documented. Some piggies can start developing silver strands among their solid colors from as young as a few months.

It is, therefore, safe to say that a young cavy that gets grey hairs on its body is not prematurely aging. It just inherited those particular genes from its parents. Greying as a result of advanced age can develop around the nose and mouth, but it doesn’t usually extend across the animal’s body.

Why Is My Guinea Pigs Fur Turning Yellow?

Yellow bottoms are usually the result of urine-stained fur, and it is especially noticeable on lighter-colored piggies. Urine stains are especially likely to occur when:

  • Your piggy has become less active as a result of age or illness.
  • The bedding in the cage isn’t absorbent enough to pull wetness away from the surface.

In addition to washing your cavy’s bottom with a guinea pig shampoo, use a more absorbent bedding. If the urine stains are the result of inactivity, check that the cage is big enough and add some toys and stimulating activities to keep your cavy active and energetic.

Why Has My Guinea Pig’s Hair Gotten Darker Over Time?

If you have adopted a pure white baby snowball and noticed it is getting dark points, it may be related to a Himalayan or Californian cavy. These beauties almost magically develop their characteristic coloring over a few months.

There is no way to predict if a guinea pig will become darker or lighter with age. Some dark-colored piggies fade out, while light-colored pets can develop darker patches over time. Factors like genetics, diet, environment, and the animal’s age all play a role.

A study of the effects of temperature on guinea pig coat color by the University of Chicago showed a mixed bag of results. Some dark-colored animals darkened further in response to cooler temperatures. At the same time, lighter-colored piggies, genetically primed to naturally lighten with age, displayed a slowing of the fading process when housed in a colder environment.

Can A Lack Of Vitamin C Affect A Guinea Pigs Color?

Guinea pigs must receive plenty of Vitamin C-rich food each day to stay healthy. A deficiency in this vital nutrient affects the animals’ overall health, and one of the first places it will be evident is on the piggy’s coat.

In addition to developing rough, coarse, or patchy fur, a diet that does not contain enough Vitamin C can make a piggy’s color appear dull. A lustrous, shiny coat is only possible if a cavy receives ample Vitamin C-rich foods.


A great thing about owning guinea pigs is that each one is unique. Whether they get lighter or darker, develop new patterns, grow interesting grey grizzling, or stay exactly the same way as when they first arrived, each one is perfect. Cavies can change colors, but luckily, it is a gradual process, so you never have to worry about it morphing overnight.