In the picture is my Guinea pig with her 2 babies from her first litter. She did have 4 but 2 died, when a guinea pig has babies there is always a chance of death, 20% (2 in 10) guinea pig mothers die in birth.
Number One Rule of Breeding: - DON'T! If you have a very good reason to breed other than stupid reasons like: - To make money. Breeding a guinea pig wont get much money at all. The supplies to keep a guinea pig itself isn't too cheap. Find a different way. - To see cute little mini mums and dads- Because your bored - Because you want more guinea pigs and more reasons.
If you’re certain your reason is good enough then here is how to breed:
Find a good breeding pair, a very healthy mother and father of a good size and aren't sick, the mother must be older than 4 months but younger than 7 months when they get pregnant as the gestation period is 2 and a half months, and a guinea pig must give birth at around 9 months at the latest.
Put the mother and father together for about 5 weeks, females come into season for about 3-4 days every 16 days, and can only get pregnant in 8 hours of the 3-4 days.
After the 5 weeks, the female should be pregnant. The stages of pregnancy are:
First week - No signs
Second week - She will drink more water
Third week - Start gaining weight
Fourth week - Her stomach area will be more firm.
Fifth week - She will look more "Pear shaped” - rounded at her stomach.
Sixth week - Might be able to feel the babies, and a little kick every now and then.
Seventh week - The babies kicking will become more frequent.
Eighth week - The mother will be more Lazy and lay down more often.
Ninth week - You will see the babies moving.
Tenth week - the babies should be born, give or take a few days.
BIRTH: You shouldn't intervene in the birth unless after about 7-10 minutes of contractions and producing no babies, or if the mother squeals on every contraction - this means she needs a vet, for a C-section. The birth should be over in 10 - 40 minutes depending on the size of the litter. The average litter size is about 2-4 babies.
THE YOUNG: When the babies are born, the mother will care for them, they will have a full coat of fur, open eyes and are usually around 3 inches long. They will eat hay from about half an hour old. And will begin eating vegetables and dry food at about a day or two old. They will get about 80% of their nutrition from their mother’s milk. If the mother is to abandon one of the young (Don't be alarmed if this happens, it happens to a lot of runt babies), you will need to feed him/her some Lactol Milk. This is available from pet stores and usually says for puppies and kittens; you should get a syringe and feed about 5ml of this every hour to your baby guinea pig.