Guinea pigs orphaned during the first four days of life may be given ground guinea pig pellets soaked in cow's milk. It is highly recommended that the boar and pregnant sow be separated prior to and after birth. All must be cleaned often. They may be housed in groups, but will establish a pecking order. Grabbing a guinea pig over its back may inhibit respiratory movements.
Guinea pigs are strict herbivores and cecal fermenters, as are rabbits and horses.
Food intake is not controlled by calories ingested, but by bulk consumed. They require special amounts of calcium, phosphorous, magnesium and potassium. Therefore, feeding table scrapes should be avoided. Guinea pigs should be fed a feed prepared specifically for the species. They will consume approximately 6 g of food and 10 ml of water per every 100 g of body weight per day.