Guinea Pigs Litter Size: How Many Babies Do Guinea Pigs Have?

Mama Guinea Pig with her newborn pups

There is nothing more adorable than a litter of pups—baby guinea pigs. But caring for baby guinea pigs and finding them homes with caring and responsible guinea pig owners is difficult. Therefore, whether you plan to breed your piggies or happen to have an unplanned pregnant guinea pig on your hands, you will be curious to know how many babies guinea pigs have in a litter. So that you can make arrangements accordingly and make sure that young pups don’t have to face any trouble after coming into this world.  

Guinea Pig Litter Size

Guinea pig litter size ranges between 1 to 8 pups; however, mostly, there are 2 to 4 pups in a litter. The largest number of pups in a litter is 17.

Before we talk about how many pups you should expect and the factors affecting the number of pups in a litter, let’s briefly talk about guinea pig reproduction and make sure that your piggy friend is pregnant and not just fat or bloating.

Read: Guinea Pig Bloat: Do Guinea Pigs Fart?

Guinea Pig Reproduction

Guinea pigs reach sexual maturity at a very young age. Where female guinea pigs mature sexually mature at around 4 to 6 weeks, male guinea pigs take around 8 to 9 weeks. However, both male and female pups could mature even earlier. Therefore, it is imperative that you separate baby guinea pigs from their mother before it’s too late.

You can expect your female pup to go into heat and be receptive to mating at the young age of 4 weeks. Here you might ask, do guinea pigs have periods? Well, they don’t have periods (menstruation), but they do go into heat for around 16 days, every two to three weeks. However, there is no bleeding or vaginal discharge.

In season, sows are only receptive to breeding for about 6 to 11 hours, mostly at night. Guinea pig gestation period ranges from 57 to 72 days, but pregnant sows usually give birth at around 63 days of pregnancy.

Now that you know the basics about guinea pig reproduction let’s make sure that piggy friend is actually pregnant.

How to Tell if a Guinea Pig Is Pregnant?

Pregnant Guinea Pig with a bigger belly

If you have been thinking that your sow is pregnant, here are some signs of a pregnant guinea pig. If you know your piggy’s habits, then you will certainly be able to notice the following signs of pregnancy in guinea pigs:

  • Your sow has come in contact with a boar. If your sow has recently come in contact with a boar, there is a great chance that the boar impregnated your piggy friend. Male guinea pigs as young as 3 weeks of age could impregnate a sow.
  • Guinea pig is gaining weight. This is one of the most obvious signs. If there are pups growing inside of your female guinea pig, she will start putting on some extra weight with each day of pregnancy.
  • Increasing food and water intake. Developing new pups inside their belly needs a lot of nutrition, and to support that, your piggy would definitely be eating and drinking more. However, you should keep a check on caloric intake as gaining too much weight could lead to Toxaemia in guinea pigs. 
  • A bigger belly means there are pups inside. While it might be hard to tell the difference between the early stage of guinea pig pregnancy, as a pregnancy enters later stages, you will be able to tell that the guinea pig’s abdomen is getting bigger.  
  • You might be able to feel the pups like lumps in the later stages of pregnancy. While feeling the baby guinea pigs growing inside of your sow, make sure that you are not applying any pressure, or you might end up hurting the mama guinea pig or little pups growing inside of her.

After confirming pregnancy, you should separate the pregnant sow from other guinea pigs, especially males. As pregnancy progresses, mama’s guinea pig will experience a roller coaster of hormonal changes, which will alter her behavior. So, it is best to keep her in a separate apartment to ensure she is safe and comfortable.

How Many Babies Do Guinea Pigs Have?

Three baby guinea pigs from a litter

A guinea pig can have anywhere between 1 to 8 pups in a litter and sometimes even more. However, there are 2 to 4 pups in a litter most of the time. Though, the highest recorded number of pups in a litter is 17. Female guinea pigs tend to have smaller litter the first time.

In the wild, guinea pigs have around 2 to 3 litter per year and around 3 to 4 pups in each litter.

Guinea pig gestation period is about two months (57 to 72 days), and around 15 hours after giving birth, sows can go into heat. And if they come in contact with a male, get pregnant and be on their way to have another litter of pups. A female guinea pig can have 5 litters in a year. Some sows can have up to eight litters in a year. So, if you keep your boar and sow together, you can expect to have a lot of pups in a year.

Guinea Pig Babies! 
Guinea pig babies are born highly developed and active. Though they weigh only about 100 grams, they are fully developed and can see and run around. They have their teeth and could start munching on timothy hay and moistened guinea pig pellets within 2 days. However, they should be allowed to nurse on their mother's milk for about 3 weeks.
baby guinea pigs nursing

Factors Affecting Guinea Pig Litter Size

The number of pups in a guinea pig litter is dependent on many factors like nutrition, guinea pig breed, age, health, genetics, boar fertility, etc.

The first-time mothers tend to have a smaller litter—1 to 2 pups. Similarly, as guinea pig grows older, the number of pups in their litter also start dropping. It is advised that you don’t breed a sow older than two years.

If a guinea pig is not properly fed and has poor health, it is going to have a smaller litter. Unhealthy and weak sows tend to have more stillborns. Keep in mind that malnourished mothers may even try to eat their stillborn babies to gather nutrition to nourish the rest of their pups.

How Many Times Can a Guinea Pig Have Babies?

While guinea pigs can have 5 litter per year and can even have up to 8 litter in a year, as we know, the average guinea pig litter size is 2 to 4 pups, and guinea pigs should be bred between 3 months to 2 years of age, math tells us a sow can have up to 18 litters during her lifetime.

However, it is best that no more than two litters are taken from a guinea pig during its lifetime. And to ensure that mother guinea pigs don’t experience any health issues, you should give her a few weeks after weaning the pups to rejuvenate before you get her pregnant again.

The Male Dominance! 
When a female guinea pig gives birth or is about to give birth, the strongest male in the vicinity gathers around and tries to assert himself as the dominant male and protect her. Around 15 hours after birth, as the mother guinea pig goes into heat, the dominant male mate impregnates the nursing mother. Therefore, if you don’t want another litter, house your queen separately.

Can Pups’ Father Has Access To the Litter?

No! Even before birth, the pregnant mother should be separated from other guinea pigs, including the father. Male guinea pigs could stress and harm the mama guinea pig and young pups. Besides, after birth, a male guinea pig could impregnate the nursing guinea pig as she goes into postpartum estrus. While pushing himself onto the nursing mother, the male guinea pig could hurt the mother and pups. So, it is best that the father is separated from the litter and the mother.

How Old Do Guinea Pigs Have to Be to Breed?

happy baby Guinea pig in garden

Female guinea pigs should be first bred between 3 to 7 months of age, and breeding them for the first time after 8 months could be really dangerous. Actually, as guinea pigs reach adulthood at around 8 months of age, the pubic symphysis (a fibrous cartilage joint between two pubic bones of the pelvis) stiffens, making normal delivery impossible.

Sows having a litter after 7 months don’t have a separation of the pelvis; thus, they just cannot deliver normally and require a Cesarean section, which is rarely successful even if performed by an experienced exotic veterinarian. Therefore, if your piglet is over 7 months of age and has never had a litter, you should keep her away from male guinea pigs. You might also want to consider getting her spayed but know that it has many associated risks as well.

While male guinea pigs can impregnate their siblings or mother as young as 1 month of age, they should be around 34 months old at their first breeding.

Breeding Guinea Pig Is Not Recommended! 
Individual guinea pig owners are advised not to breed their piglets for two reasons: It is pretty hard to find good homes with loving and responsible guinea pig lovers for new pups. Breeding guinea pigs is complex and is known to reduce the lifespan of sows.

Can a 4-Week-Old Guinea Pig Get Pregnant?

Yes, a 4-week-old guinea pig can get pregnant. As young as a 3-week-old pup could impregnate his mother or female siblings. Therefore, you should separate male pups from the litter as soon as they are weaned in the third week.

Guinea pigs sexually mature really fast. Guinea pig pups are actually born “precocial.” They are highly developed and active. They start feeding on solid food like timothy hay and pellets as soon as 2 days of age. However, they should be allowed to feed on their mother’s milk for around 3 to four weeks.

Newborn pups in their cage

Do Guinea Pigs Kill Their Babies?

While female guinea pigs would never eat their pups on purpose if there is a stillborn pup or there is not enough food to nourish the rest of the pups, the mother guinea pig might eat the stillborn baby. A female guinea pig may also eat one of its babies if she is malnourished and unable to nurse her pups.

A male guinea pig might eat his babies if he is territorial and feel threatened. Male guinea pigs should be kept away from the litter as well as the mother. 

Final Verdict: How Many Babies Do Guinea Pigs Have?

Guinea pig litter size could range anywhere between 1 to 8 and even more. The largest recorded guinea pig litter size is 17. In their first litter, guinea pigs have 1 or two pups, and 2 to 4 in their subsequent litter. A Guinea pig can have around 2 to 8 litters per year. However, it is recommended that you don’t have more than two litter per guinea pig per lifetime.

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