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Guinea pig's life cycle

guinea pig life cycle

Photo by Jaroslaw Slodkiewicz

Guinea pigs are popular pets and for a good reason. They are cute, cuddly, and make great companions! And if you think about getting a guinea pig you may want to know more about how it grows.

A healthy, well-cared-for guinea pig usually lives five to seven years. And as a small rodent, it grows from a baby gunea pig to an adult extremely fast, within the first 6 months of its life.

Read on to learn about the guinea pig life cycle, from when they're born to when they get old, and everything in between. You'll also find some tips, like the best time to breed guinea pigs.

Life stages of a guinea pig

Like all creatures, guinea pigs go through a typical life cycle with four main life stages:

guinea pig life cycle chart

Let's take a closer look at each of them


Guinea pig infants are born with their eyes already open and with a nice fur, unlike rabbit kits and hamster pups. They weigh around 3 to 3.5 ounces at birth. Although they can walk (rather wobble) already, the babies are vulnerable and dependant on their mother.

Infant guinea pigs will start to eat solid foods within two to three weeks.

Watch these baby guinea pigs being born:


two adolescent guinea pigs eating carrot straws

Photo by Bonnie Kittle

Adolescence begins when young guinea pigs are being weaned from their mother. This usually happens at the age of 3-4 weeks.

At this time guinea pigs will start to become more independent. They will learn to groom themselves, and their coat will become more distinct. They will also start experimenting with different foods, and their social behavior will change.

Adolescent guinea pigs are social, playful, and adventurous. It's best to ensure they have ample space to explore but are kept isolated from other, potentially predatory pets. Larger pets may place the young guinea pigs under undue stress, disrupting their sleep cycles and leading to growth deficiencies.

The period of adolescence for guinea pigs is relatively short compared to their life spans. They will only be considered adolescents for approximately three to four months before entering adulthood.


people petting an adult guinea pig

Photo by Matthew Halmshaw

At the age of 5-6 months guinea pigs will reach adulthood and their full size. They will continue eating a diet of Timothy and oat hay, which should be available constantly, as they need it to curb the growth of their teeth (which constantly grow), along with a serving of fresh vegetables.

Adult male guinea pigs may become territorial and aggressive if new guinea pigs are introduced into the same cage. Female guinea pigs are much more tolerant of others and can live peacefully with other females.

Sexual maturity

Guinea pigs become sexually mature around the same time as when they reach adulthood. Age does not matter when it comes to male guinea pigs. As long as they are sexually mature, they can reproduce.

However, female guinea pigs have a short period to safely reproduce. They must breed within the first 10 months of their lives before their pubic symphysis fuses. It is actually less safe for them to breed closer to 10 months of age. Therefore, the best time to breed female guinea pigs is as soon as they reach sexual maturity.

Guinea pig gestation takes between 2 to 2.5 months, and it's most typical for the mother to give birth to three or four pups at once.

Old age

As guinea pigs get older, their coat may start to thin out. They may also develop health problems such as arthritis, cataracts, or heart disease. Various health problems that arise toward the end of a guinea pig's life may be influenced by factors throughout their life, including diet, exercise, and overall quality of life.

It's important to provide a proper care during each life stage of a guinea pig, espetially as they get older. This is the only way to ensure your lovely pet will live a happy and long life.

Guinea pig's life cycle: FAQ

when are guinea pigs weaned?

Baby guinea pigs are wiened at the age of 3-4 months

when does a guinea pig reach adulthood?

A guinea pig reaches adulthood by the age of 6 months.

what age is a guinea pig fully grown?

Guinea pigs are fully grown as they reach adulthood by the age of 6 months

when do guinea pigs reach maturity?

Guinea pigs reach their sexual maturity by the age of 6 months. For female guinea pigs, the age from 6 to 10 months is the best age to reproduce

how long does guinea pig gestation period last?

A guinea pig gestation period lasts 2 to 2,5 months (59 to 72 days).