Termination of early pregnancy in sheep with dinoprost or cloprostenol: comparison of two commercial preparations.
The response of the ovine corpus luteum of pregnancy to the luteolytic effect of prostaglandin F2 alpha (dinoprost) and its analogue, cloprostenol, was tested in both superovulated and untreated ewes by monitoring plasma progesterone concentrations at the time of 'material recognition' and beyond (days 13 to 30). On days 13, 16 and 28, the majority of the superovulated ewes were refractory to 10 mg of dinoprost. The luteolytic efficacy of 250 micrograms of cloprostenol was compared with 10 mg of dinoprost on day 20 of pregnancy in superovulated and untreated animals and the two prostaglandins were also compared on days 26 and 30 in animals previously unresponsive to dinoprost. Generally, cloprostenol was more effective than dinoprost because there was less refractoriness on day 20 and no refractoriness on days 26 and 30 to this prostaglandin. No difference in the sensitivity to this drug was found between the superovulated and untreated groups on days 20 and 26.
Audicana
L
L
Department of Surgery and Reproduction, University of Glasgow Veterinary School.
Harvey
M J
MJ
D000028:Abortion, Induced / Q000662:veterinary*; D000818:Animals; D003008:Cloprostenol / Q000008:administration & dosage / Q000494:pharmacology*; D003338:Corpus Luteum / Q000187:drug effects*; D015237:Dinoprost / Q000008:administration & dosage / Q000494:pharmacology*; D004973:Estrus Synchronization; D005260:Female; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D012756:Sheep; D013480:Superovulation; D013997:Time Factors
D003008:Cloprostenol; D011374:Progesterone; D015237:Dinoprost