Breeding

Young female pigs, which have not yet been mated, are called "gilts"

Good breeding performance is essential for any sow farm. There is no profit without piglets. Pigs reach puberty at the age of 6 to 9 months. The onset of sexual maturity varies with breed, season and way of rearing. It is important for the herdsman to recognize a sow in heat, because only properly timed mating is successful.

A sow in heat tries to mount other females, utters grumbling sounds and becomes alert to the presence of a boar. In his company she assumes a rigid, immobile position, called "standing heat", which lasts about 3 days. Heat detection in individually tethered sows is more difficult. The herdsman provokes the standing response by applying manual pressure to the back of a sow. However, it is more effective to walk a boar down the aisles to attract the sows additionally.

Mating has to occur each day the sow is in standing heat. Depending on facilities and production system natural breeding (pasture breeding, pen mating, hand mating) or artificial insemination are preferred. As a result of intensified production pasture breeding is being replaced by other mating systems. Pen mating is the most common way of natural breeding. One or two boars are grouped with about 15 sows. Hand mating is more time consuming, but it has many advantages. The herdsman selects females in standing heat and moves them to a breeding pen accompanied by a boar. This enables him to observe the mating behavior, record the breeding dates and control the number of matings per boar per day.

If the heat returns after 21 days the sow is not pregnant and has to be mated again. A prerequisite to this method is a successful heat detection by a keenly observant herdsman. In large units pregnancy diagnosing is done by ultrasound examination. The normal length of pregnancy is 114 +/-4 days. It varies with the breed of sow and boar and tends to be longer in sows which expect large litters. While purebred breeders mate always only boars and sows of the same breed, crossbreeding ideally combines good characteristics of different breeds.