Artificial insemination is the process of placing semen (frozen or fresh) into the body of the uterus during the period of oestrus.

Artificial insemination is often used to join multiple cows and heifers at a single point in time following a synchronisation program. Artificial insemination can be carried out at a certain time after oestrus has commenced in an individual animal or at a fixed time for the entire herd, based on a certain time associated with predictable physiology proceeding a synchrony program