Ovarian follicular responses in dairy cows treated with GnRH and cloprostenol.
Lactating, nonpregnant (with a corpus luteum) Holsteins were given 100 ug GnRH (n = 12) or saline (n = 12) and 500 ug cloprostenol 6 d later. Following luteolysis, ovulation occurred 10.1 +/- 0.2 d (range, 9-12 d) after GnRH and 8.6 +/- 1.0 d (range, 3-12 d) after saline (differences between groups: means, P > 0.05; variability, P < 0.001). Treatment with GnRH and cloprostenol resulted in a relatively synchronous ovulation.
Kastelic
J P
JP
Research Centre, Agriculture and Agri-Food Canada, Lethbridge, Alberta.
Mapletoft
R J
RJ
D000822:Animal Husbandry; D000818:Animals; D002417:Cattle / Q000502:physiology*; D003008:Cloprostenol / Q000494:pharmacology*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D007774:Lactation; D006080:Ovarian Follicle / Q000187:drug effects*; D010062:Ovulation Induction / Q000662:veterinary*; D011247:Pregnancy
D007987:Gonadotropin-Releasing Hormone; D003008:Cloprostenol