Sow and litter performance following farrowing induction with prostaglandin: Effect of adjunct treatments with dexamethasone or oxytocin

Abstract

Objective: To evaluate effects of dexamethasone (DEX) and oxytocin in prostaglandin F2α (PGF) farrowing-induction protocols. Materials and methods: In Experiment One, 144 sows were induced with two injections of PGF 6 hours apart (split dose) with or without injection of 20 mg DEX with the second PGF. Interval from initial PGF to farrowing, duration of farrowing, litter size born alive, number of stillbirths, and piglet weight gain to 10 days of age were recorded. In Experiment Two, 106 sows were induced with single or split-dose injections of PGF with or without injection of 20 IU oxytocin 24 hours after initial PGF. Time to onset and duration of farrowing were recorded, as were requirement for manual intervention, total litter size born, and incidence of stillbirths. Results: For sows farrowing 24 to 32 hours after initial PGF injection in Experiment One, there was no effect of DEX treatment on the PGF-to-farrowing interval, duration of farrowing, or piglet growth and survival to 10 days of age. In Experiment Two, more sows farrowed by 32 hours after the split dose of PGF than after a single dose (P < .05). The PGF injection protocol did not influence the farrowing response to oxytocin. Oxytocin injection was associated with higher stillbirth rates when cervical dilation was incomplete. Implications: These data do not support a role for corticosteroid in farrowing induction protocols. Oxytocin administered 24 hours after PGF (single or split dose) was associated with farrowing problems, suggesting that routine use of oxytocin in periparturient sows is contraindicated.