There is little cuter than a baby guinea pig. Unlike most mammals they’re born fully-furred, with their eyes open and able to run around within moments of birth. They’re also quite a bit larger than you might expect, being comparable to a small hamster.
Little wonder, then, that so many people want to breed guinea pigs.
However, breeding guinea pigs is not an activity which should be approached lightly. Not only must you satisfy yourself that you have suitable homes for any guinea pigs, but you also need to understand that there are serious health risks for pregnant guinea pigs.
Generally speaking, experts recommend that guinea pigs should only be bred by professionals following a very strict system to minimise the risk to mother and pups.
The Suitable Pair
Female guinea pigs reach sexual maturity at a surprisingly young age. It is not unusual for them to be capable of reproducing from as little as 4-8 weeks of age. This means that great care should be taken to separate out young guinea pigs in order to prevent unwanted pregnancies.
If you do decide to breed guinea pigs then it’s critical that you select a female of a certain age. She should not be too young (most authorities recommend a minimum age of 3 months) but she also mustn’t be too old.
An odd quirk of guinea pig biology is that the ligaments joining together the pelvic bones can harden with age. This can make birthing difficult. In older females a Caeasarean may be required. Even then, there are considerable risks, and it is not uncommon for mother or young to die as a result.
Ideally, if a female is to be used as a sire then she should be bred before she is six months of age, which will help to set her hips and make future births rather less fraught.
Males may be of almost any age, though older males tend to lose vigour.
Introducing the Pair
Guinea pigs are typically quite docile and sociable creatures. While adult males (boars) will fight, females and pairs rarely do so.
The best method of introduction is to place the male into the female’s cage. This reduces stress on the female. The pair can then be left together until you’re confident that the female is carrying young.
How Do I Know If My Guinea Pig is Pregnant?
The most obvious sign of pregnancy in guinea pigs is that their food intake increases dramatically, while they very visibly put on weight. Handled gently, you may even be able to feel the babies in her belly.
To be certain, a vet can examine your guinea pig, where they will be able to tell you how many babies you can expect, and to check the family for health.
Gestation in Guinea Pigs
Gestation periods in guinea pigs can vary widely. The average gestation period is roughly two months – with 60-70 days being typical. Be aware that the longer the gestation period, the more chance there is of a miscarriage, so long gestation periods can be a bad omen.
During this time the mother will need additional care. It is wise to handle your guinea pig as little as possible. This reduces stress, and prevents the chance of a baby being accidentally injured.
Additionally, offer your female plenty of food and water, with a particular emphasis on calcium-rich foods like watercress.
As you get closer to the date of birth it can be wise to remove the male entirely. While it is sad to leave her on her own, most guinea pig mothers birth best alone. In addition, the mother can fall pregnant again within hours of birth. As pregnancy is so physically draining it is best to remove the male, thus preventing a second pregnancy soon afterwards.
Guinea pigs have quite small litters. An average number of piglets is between one and four, though larger litters are sometimes experienced.
The young are astonishingly precocious, and may be seen trying adult food within days. Most baby guinea pigs are fully weaned between 14 and 28 days. At this point the sexes should be separated to prevent any unwanted pregnancies.