How to Breed Pigs. Pigs can breed often, have a short gestation period and produce large litters. These factors make breeding pigs lucrative. You only need a few males to breed many females. A single boar, at least a year in age, can breed with 50 females housed in stalls, or 40 located in a pasture.
Select sows for mating that are at least 10 months old. Breeding males should be at least 8 months old. Boars that age can be bred with about 12 females. Use older males to service larger numbers of females.
Look at the sows' vulvas for swelling that indicates a period of fertility. During this time, younger sows can be bred on their first fertile day, while older sows should be bred the next day.
Breed the pigs during each fertile period until pregnancy is achieved. The gestation period is about 113 days.
Treat the mother for worms and lice before babies are born to prevent the newborns from being infected. Give the mother an immunization for erysipelas before the babies are born to protect the offspring.
Keep the pen clean and sanitary, cleaning it regularly with a mild cleanser so that infection and disease will not spread from the pigs to the newborns. Gently wash the pregnant pig before the piglets are born.