Induction of Parturition in Swine with Prostaglandin F2α2

Abstract

Pregnant gilts and sows were administered prostaglandin F _2α by intravenous infusion or by intramuscular injection in an effort to induce parturition. The average interval from the start of infusion until birth of the first pig was 28.9 ± 1.9 hr. in gilts receiving PGF_2α which occurred at a mean gestation length of 109 ± 0.03 days as compared to 78.9 ± 18.4 hr. and 111.5 ± 0.02 days, respectively, in control gilts. Plasma progesterone concentration decreased from a mean of 4.4 ng/ml at the start of PGFaa infusion to 1.3 ng/ml 10 hr. later. Control gilts had mean progesterone levels of 5.6 and 5.3 ng/ml, respectively, at the start and end of the infusion period. At parturition mean progesterone levels of PGF_2α and control gilts were similar, being 1.6 and 1.9 ng/ml for control and treated gilts, respectively. There was no apparent cause and effect relationship between elevated levels of corticoids and parturition. After the intramuscular injection of 0, 2.5 and 5.0 mg PGF_2α parturition followed, on the average, at 85 ± 7, 29 ± 3 or 30 ± 1 hr., respectively (P< .05). The average gestation length was significantly shorter (P< .05) in treated gilts but, even so, the number of live pigs at birth and piglet survival rate were unaffected by PGFα treatment. Copyright © 1974. American Society of Animal Science . Copyright 1974 by American Society of Animal Science.