The effects of treatment with cloprostenol or dinoprost within one hour of induced parturition on the incidence of retained placenta in cattle

摘要

Two experiments were designed to determine whether prostaglandin treatment within one hour postpartum would reduce the incidence of retained placentas after induction of parturition in beef cattle. In the first experiment, 70 cows were induced on day 276-278 of gestation with the combination of 500 μg cloprostenol and 25 mg dexamethasone (CP + Dex). Within one hour after parturition, cows received either 500 μg CP or 25 mg of dinoprost (DI). The incidence of retained placenta (RP) was 64.3% in induced groups and 0% in noninduced control cows and postpartum treatment with either CP or DI had no effect on placental retention.A second experiment, utilizing 132 cows and heifers, was conducted to determine whether induction with Dex alone, rather than with CP + Dex, would influence the rate of placental retention after postpartum treatment with either CP or DI. The incidence of retained placenta ranged from 28.5 to 58.3% in induced females but was 0% in noninduced control females. As in the first experiment, postpartum prostaglandin treatment had no effect on placental retention.The results of these experiments do not support the use of prostaglandins within one hour of induced parturition to reduce the incidence of retained placentas.