Piglets born in nests
The gestation period varies according to the age of the expecting mother. For first time mothers, it lasts 114–130 days, while it is 133–140 days in older sows. Sows about to give birth isolate themselves from the main group and build a nest constructed from twigs, grasses and leaves. Farrowing often occurs once a year between March and May. The average litter consists of four to seven piglets, with the maximum being 10-12. After one or two weeks, the sow and piglets leave the nest and rejoin the group.