title: Effect of oxytocin treatment during oestrus on the ovulation rate of Merino ewes.
abstract: The effect of oxytocin treatment on the ovulation rate of Merino ewes was investigated. Intravenous doses (0.1 IU) of oxytocin were administered to synchronised ewes (n = 54) every 30 min for a 24 h period beginning at the onset of oestrus. Laparoscopic examination of the ovaries of all ewes that had displayed overt oestrus following sponge withdrawal was performed 10 d after the beginning of oxytocin treatment to determine the number of corpora lutea per ewe. The ovulation rates of the treated and control groups were 174.5% and 144%, respectively (p < 0.01). It would appear that a higher ovulation rate can be obtained by repeated low-dose intravenous injection of oxytocin during oestrus.
authors.affiliation: Grootfontein Agricultural Development Institute, Middelburg, South Africa.
authors.forename: P R
authors.initials: PR
authors.lastname: King
authors.forename: W A
authors.initials: WA
authors.lastname: Coetzer
mesh_terms: D000818:Animals; D004971:Estrus / Q000187:drug effects*; D005260:Female; D010060:Ovulation / Q000187:drug effects*; D010121:Oxytocin / Q000494:pharmacology*; D012756:Sheep / Q000502:physiology*
chemical_list: D010121:Oxytocin