EFFECT OF SPERM CAPACITATION AND FERTILIZATION MEDIA ON IVF AND EARLYEMBRYO DEVELOPMENT OF PREPUBERTAL GOAT OOCYTES

Experiments were carried out to develop an improved IVF system for pre pubertal goat oocytes matured in vitro. Cumulus oocyte complexes (COC) were obtained by slicing ovaries from slaughtered prepubertal goats. Oocytes were matured in TCM199 supplemented with 20% estrous goat seru m (EGS) + 10 mu g/mL FSH + 10 mu g/mL LH + 1 mu g/mL estradiol 17 beta for 27 h at 38.5 degrees C in 5% CO2 in air. In Experiments 1 and 2, freshly ejaculated spermatozoa were capacitated in 1 of 3 media: TALP/ H, modified Defined Medium (mDM) and mH-M199 with 50 mu g/mL heparin f or 45 min. Matured oocytes were fertilized in TALP, mDM or mH-M199 in Experiment 1 and in TALP in Experiment 2. In Experiment 3, three media were used for sperm capacitacion and fertilization: Treatment A (cont rol group): spermatozoa were capacitated in mDM with 50 mu g/mL, hepar in for 45 min and fertilized in TALP medium with 1 mu g/mL hypotaurine ; Treatment B: spermatozoa were capacitated in mDM with 50 mu g/mL.hep arin + 388 mu g/mL caffeine for 30 min and fertilized in TALP medium w ithout hypotaurine; Treatment C: spermatozoa were capacitated in mDM w ith 50 mu g/mL heparin for 45 min and fertilized in TALP medium with P HE (20 mu M penicillamine, 10 mu M hypotaurine and 2 mu M epinephrine) . At 24 h post insemination, the ova were transferred to a granulosa c ell monolayer, and early embryo development was evaluated until Day 8. In experiment 2, the results show, that mDM plus heparin for sperm ca pacitation and TALP medium with hypotaurine for oocyte fertilization p rovided the highest proportion of penetrated oocytes, both total numbe r (79.6%) and normal fertilization (55.1%), whereas the use of caffein e (44.6 and 31.2%, total and normal fertilization rate, respectively) and PHE (31.8 and 20.6%, total and normal fertilization rate, respecti vely) as motility enhancers did not improve the results obtained in th e control group (48.7% and 37.2%, total and normal fertilization rate, respectively). These were no differences for the results of morulae a nd blastocysts. (C) 1998 by Elsevier Science Inc.