[Studies on biotechnical ovulation synchronization in young sows. 3. Report: ovulation onset, ovarian findings and results of fertilization after metallibur, 750 IU PMS, with and without 500 IU HCG with varied treatment time].

Fourty-eight gilts were treated with Turisynchron-Prämix (Turi.) and PMS (750 IU; 24-hours a. Turi.). One-half of the animals receaved additionally 500 IU HCG (fourth day a. Turi.). Performing treatments (Turi., PMS, HCG) either between 8 and 9 a.m. or 3 and 4 p.m. resulted in 2 experimental (HCG) and 2 control (without HCG) groups, each consisting of 12 animals. Double insemination took place according to treatment times at the fifth or the fifth and sixth day a. Turi. The experimental animals underwent laparotomy at the sixth day between 9 and 12 a.m., the conerols between 1 and 4 p.m. at the sixth or 9 and 12 a.m., at the seventh day a. Turi. Oviducts were flushed either at laparatomy or on slaughter to establish fertilization. From 24 experimental animals 20 ones had ovulated between 42-53 h p. HCG, and at slaughter 22 did so. The period of ovulation is mainly assumed near and immediately after 42 h p. HCG. In controls ovulation could be established in 3 of 15 animals laparotomized up to 152 h a. Turi. and in 8 of 9 animals laparotomized up to 168 h a. Turi. At slaughter there were in all 22 animals of the 2 control groups which had ovulated. In the rate of ovarian cysts (25-33%) and fertilized ova no remarkable differences were found between the groups.