Guinea Pig babies are born fully developed and are able to run around in less than two hours. It is best to let the mother pig take care of the babies for at least the first 12 hours. She needs to clean the piglets and herself. The mother Guinea Pig will know what to do even if she has never had a litter before. It is good to leave some extra food near the mother because she will be hungry after giving birth and she won't have to leave the babies. If you have several adult pigs, especially female, they will help take care of the litter when the mother needs to go eat or rest. In fact, females that have had litters before may try to nurse the new litter even though they physically can not produce milk.
First day: The babies will begin looking for food from the mother after about 6 hours. The babies will not venture from the nest in the first day. If you are very careful you may pickup the babies after about 12 hours. They will try very hard to get away, but once you hold them, cover their head, and warm them up, they will fall asleep. It is much fun to put the whole litter in a towel. They will pile on top of one another and fall asleep. Some piglets will learn to squeak in the first day. This squeaking is a warning to the mother that something is wrong. If the babies starts squeaking the mother will become very alarmed and should be put back right away so she isn't stressed.
Second day: The babies may begin to follow the adults around their area. Some adventurous piglets may begin to venture out on their own. If the babies feel they are lost they will begin to squeak until an adult comes to the rescue. The babies will start their imitative behavior trying to chew on things and even trying to chew on adult food. They will squeak more often to let the mother know that they are hungry. Be sure to observe the feedings and make sure that all piglets are interested in feeding. It is rare but some piglets will not eat much from the mother and will not gain weight as fast as the rest of the litter.
Third day: The piglets are all over the house. They make lots of noises and enjoy testing their new legs. More physically advanced babies will attempt eating adult food in very small amounts, however, some babies ignore adult food and rely on nursing.
Beginning of the second week: The piglets will alternate between nursing and eating adult food. The babies will begin to follow adult pigs that are not their mother. Will begin trails. (trail is where they begin to run around as if on a specific yet invisible trail and run it over and over again. This behavior is a result of their originally living in grassy areas where they would survive by running in trails to avoid predators)
End of second week: The babies will begin to venture into the food area and eat by themselves. The bronco is starting. (the bronco is where they jump around like a bucking bronco)
Third week: You should now be able to determine whether the piglets are male or female. Purr Dance (boys). Mounting behavior. Much trails and bronco.
Fourth week: May begin biting owner doesn't hurt. Independent of mother except for some nursing. Will still tend to herd around mother when frightened, cold or sleeping.
Fifth week: Mother will begin to not allow nursing. Adult males may start fighting with young males. The earliest babies can be separated from the mother.
Sixth week: Will start fighting with adults and each other if space is limited. It is best to remove babies at this time.