SOWS ARE EITHER MATED OR ARTIFICIALLY INSEMINATED WHEN THEY COME INTO OESTRUS.
Semen is collected from boars and processed in an on-site laboratory. Technicians check for quality, i.e. concentration, motility and morphology, before diluting with an extender which enables one ejaculate to be used across many sows. Doses are then packaged and stored between 15-19 ºC until they’re ready to be used.
Stockpeople check sows and gilts for signs of heat each day until they return to oestrus. Gestating sows are also checked for signs in case they have lost their pregnancy. Sows in oestrus are then either mated by a boar or artificially inseminated.
Sows are artificially inseminated by passing a plastic catheter into the sow’s cervix and attaching the semen pack. Semen is drawn into the sow’s uterus while she has nose to nose contact with a boar. AI is not only used in place of natural mating to increase the rate of genetic gain, it also improves safety for our workers, as the amount of contact with these big boars is reduced.
Age of mating – female pigs are mated for the first time when they are 28 - 32 weeks old. Young boars are trained from 26 weeks of age.
Heat cycles – pigs are able to reproduce all year round and come into oestrous (‘on heat’) every 21 days.
Gestation period – a pig’s pregnancy lasts for approximately 116 days. An easy way to remember this is 3 months, 3 week and 3 days.