Abstract

Yearling red deer hinds were treated to advance the time of the normal onset of ovulation so that mating and subsequent calving would occur about 1 month earlier than usual. All hinds, except for the untreated controls had 15 days of intravaginal progesterone treatment beginning on 28 February. At progesterone withdrawal hinds were either untreated, or given pregnant mare's serum gonadotrophin (PMS) or gonadotrophin-releasing hormone (GnRH). Stags were introduced on 14 March and the hinds laparoscoped 7 or 12 days later to record the presence or absence of an induced ovulation. Untreated hinds had a very low incidence of ovulation prior to the onset of the normal breeding season. While the use of progesterone alone marginally increased the number of hinds ovulating, PMS or GnRH treatment was generally necessary to induce ovulation. However, assessed from calving records, fertility at the induced ovulation was poor.

KM, Henderson, RL Ellen, LC Savage, K Ball, and KP McNatty

Proceedings of the New Zealand Society of Animal Production, Volume 46, , 157-160, 1986