[Induction of synchronized labor on commercial swine farm complexes with the synthetic prostaglandin F2 alpha analog, cloprostenol].

Experiments were carried out under conditions existing in industrial swine complexes with two groups of experimental sows: I group -- consisting of 17 sows injected on the 108th and 109th day of pregnancy with 175 g cloprostenol, and II group -- consisting of 145 sows injected on the 110th, 111th, 112nd and 113th day of pregnancy. On 125 sows of 110--111 day of pregnancy a reduced single dose application of 150 g cloprostenol was tested. Studies were performed on the period to farrowing following cloprostenol injection, the duration of farrowing, the changes in physiological behaviour, the number of viable and unviable new born piglets, the results following weaning of offspring at the age of 28 days and on the economic evaluation of the technology of forced synchronized and programmated farrowing in industrial swine complexes. It was established that the synthetic analogue of prostaglandine F2L (cloprostenol) applied once by intramuscular injection at a rate of 175 g per sow on the 110--113th day of pregnancy has a luteinizing effect and leads to forced synchronized farrowing of 75--80% of the sows, 27 +/- 5 h post treatment. Similar results were obtained by a reduced rate of 150 g cloprostenol. Synchronized farrowing provides an opportunity for simultaneous weaning of equated piglet groups and contributes for better labour organization and veterinary service. Shortening the pregnancy period below the 110th day is not feasible physiologically and economically.