Plasma concentrations of 13, 14-dihydro-15-keto prostaglandin F(2alpha) and progesterone during oxytocin-induced oestrus in the goat.
Fertile oestrus was induced in dairy goats by sub-cutaneous administration of 100 i.u. oxytocin per day between days 3-6 of the oestrous cycle. Peripheral plasma concentrations of 13, 14-dihydro-15-keto-prostaglandin F(2alpha) (PGFM), the major metabolite of prostaglandin (PG) F(2alpha), were elevated significantly (P<0.001), relative to controls, 30 minutes after oxytocin with peak values of between 300-800 pg ml(-1). Unlike control animals, plasma progesterone concentrations did not rise in the oxytocin-treated group after day 4. These results lend support to the hypothesis that the luteolytic effect of oxytocin in goats may be mediated via uterine PG production.
Cooke
R G
RG
Department of Veterinary Physiology and Pharmacology, University of Liverpool, Liverpool L69 3BX UK.
Homeida
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