[Effectiveness of different treatment regimens for inducing labor in sows with prostaglandin F2 alpha]

2 experiments were applied to 401 gilts and sows to verify the effects of different injection dates and PGF2 alpha doses (Prostin F2 alpha) on the beginning and duration of parturition. PGF2 alpha was intramuscularly injected on the 112th or 113th days of pregnancy. Doses were 5.0 mg or 7.5 mg, 10.0 mg or 12.5 mg. One single injection of not less than 7.5 mg of PGF2 alpha from the 112th day of pregnancy caused normal births within 48 hours from injection in more than 85 per cent of the animals involved, with farrowing after the 116th day of pregnancy being ruled out. No correlatons were secured between litter sizes of treated sows and the time which elapsed between treatment and partiturition.