THE INFLUENCE OF SEMEN PREPARATION AND CU LTURE-MEDIUM ON THE SUCCESSOF IVF IN CATTLE

The effect of two semen-preparation methods and the presence and absen ce of capacitation-inducing supplements in the fertilization medium on IVF-results were examined in a 2 x 2 factorial design. In vitro matur ed oocytes were fertilized either with transmigrated (TM) or with swim -up (SU) prepared native semen. In the first group, the fertilization medium contained 0.8 mug/ml heparin, 1.2 mug/ml hypotaurine and 0.2 mu g/ml epinephrine. However, in the second group, no capacitation-induci ng or motility-enhancing substances were used. After SU-treatment, the supplements were necessary to obtain sufficient fertilization results . In the second group (non-supplemented medium), the percentages of pe netrated and fertilized oocytes were decreased significantly (P < 0.00 1). By contrast, transmigrated semen required no additional supplement ation of the fertilization medium. The penetration and fertilization r ates of this semen-preparation method were equal in both groups.