The mares breeding year is divided into two parts: Anoestrus and Oestrus. This is the period where the mare is not receptive to the stallion, does not show regular signs of being 'in season' and can be more stable in her moods. Oestrus is the period where the mare exhibits good regular 'seasons' and she will 'show' and be generally receptive to the stallion during teasing. Oestrus is the beginning of the ovulatory season.