When levels of neonatal mortality are considered too high or there is a need for relatively high levels of cross fostering, a protocol of induced farrowing should be implemented to facilitate farrowing supervision. Before implementing an induction protocol the normal gestation length for the farm should be established and sows not induced more than 2 days in advance. Earlier injections will result in low birthweight pigs with potentially compromised lung development. For optimal induction, inject prostaglandin or an analogue into the vulva at the label or 50% dose in the morning and again 6 to 8 hours later. Do not inject oxytocin routinely (e.g. at 24 hours after initial PGF injection) as this will increase stillbirths and neonatal mortality because the strong uterine contractions will cause blood flow restriction to the uterus with consequent fetal hypoxia. Injections of up to 10 IU oxytocin can be given strategically for potential problem sows and to older slower farrowing sows after the delivery of the 7th pig.
Kirkwood, Roy N.
"Induction of Parturition in Sows,"
The Thai Journal of Veterinary Medicine: Vol. 45:
4, Article 1.
Available at: https://digital.car.chula.ac.th/tjvm/vol45/iss4/1