[The inhibition of meiosis of bovine oocytes using biologic of synthetic inhibitors].

About 1,200 cumulus oocyte complexes were used in an attempt to investigate the influence in vitro of various biological or synthetic inhibitors on meiosis of bovine oocytes. The biological inhibitor used was a low-molecular protein fraction (OMI) of bovine follicle fluid. N6, O2-dibutyryl-cAMP (0.3-1 mol/l), hypoxanthine (4.0 mol/l), adenosine (0.75 mol/l), and nicotinamide (20.0 mol/l) were the synthetic inhibitors. The OMI-active lyophilisate caused inhibition by 34 percent after 24 hours of culturing. Meiosis was inhibited by 15-28 percent by the synthetic inhibitors. Eight transferable embryos have so far resulted from in vitro fertilisation of oocytes of extracorporal non-ovulatory maturation. Pregnancy was achieved in heifer recipients by tubal transfer.