Abstract
Twelve 13-month-old crossbred pregnant gilts were used to determine the effects of prostaglandin F2α(PGF2α) on the length of gestation and endocrine changes at parturition. At day 105 of gestation, gilts were anesthetized and indwelling cannulae were placed into the anterior venae cavae. Gilts were injected intramuscularly with either 10 mg PGF2α or saline on day 108 of gestation, with parturition subsequently occurring at 33 ± 2 hr and 105 ± 15 hr (P<.005), respectively. Plasma progesterone concentrations were similar in PGF2α and control gilts prior to treatment and at 4 hr after treatment, but progesterone was reduced during 8 to 24 hr after PGF2a treatment (P2α treatment (P.10). At parturition plasma concentrations of progesterone, estrone, corticoids and LH were similar in PGF2a and control gilts but estradiol concentrations were less in the treated gilts (P2α given on day 108 of pregnancy will induce synchronized parturition in gilts. Copyright © 1977. American Society of Animal Science . Copyright 1977 by American Society of Animal Science.