| The present study was conducted to investigate activation of in vitro maturated goat follicular oocytes and parthenogenetic embryos development in vitro. The main results are as follows:1. Ionomycin, Ca-A23187 and ethanol all can activate the goat oocytes efficiently. The activation and morula rates of 2.5 mol/ L, 5.0 mol/ L and 10.0 mol/ L ionomycin were 54.0%, 58.2%, 57.9% and 1.5%, 4.2%, 0, respectively. There was no significant difference among all groups. The activation rates of 5.0 mol/ L, 10.0 mcl/ L , 15.0 mol/ L and 20.0 mol/ L Ca-A23187 were 31.0%, 46.4%, 41.8% and 45.8%, respectively. The activation rates of 10.0 mol/ L were significantly higher than that of 5.0 mol/ L (P<0.05). The activation rates of 3%, 7%, 11% and 15% ethanol were 40.0%, 61.4%, 63.0% and 67.9%, respectively. The activation rates of 7%, 11% and 15% ethanol were significantly higher than that of 3% (P<0.01), respectively. The death rate of 15% ethanol activated oocytes was 15.4%, significantly higher than that of 3%, 7% and 11% ( P<0.05), respectively. The morula rates of 7% and 11% ethanol were 3.5% and 1.8%, respectively.2. In the electronic activation media including Ca2+, using the electronic pulse at different voltage 1.00 kv/cm, 1.25 kv/cm, 1.50 kv/cm and 1.80 kv/cm to stimulate the oocytes twice for 80 us, the activation rates were 48.4%, 54.3%, 55.8% and 45.1%, respectively, with no significant difference (p>0.05) . Increasing the frequency of stimulus did not improve the activation rates. The activation rates of oocytes and theviability of the different periodical cells, stimulated with electronic pulse three times, twice and once, did not differ significantly (p>0.05). The electronic activation media without Ca2+ could not activate the oocytes efficiently.3. After cultured for 18 h, 21 h. 24 h, 27 h, 30 h and 36 h in vitro, the activation rates of oocytes were 27.4%, 38.4%, 42.1%, 58.2%, 60.0%, 64.7% and 73.1%, respectively. The activation rates of oocytes cultured for 36 h, 33 h and 30 h were significantly higher than those cultured for 18 h, 21 h and 24 h (p<0.01), respectively. The activation rates of oocytes cultured for 27 h were greatly significantly higher than those of matured for 18 h and 21 h (p<0.01) and also significantly higher than that of cultured for 24 h (p<0.05), respectively. After cultured for 8 days, the rates of morula of oocytes cultured for 24h and 27h were 2.2% and 4.2%, respectively. The oocytes cultured for other hours did not develop to the morula stage.4. With the increase of cumulus cells around the oocytes, the activation rates drop significantly. The oocytes with 4 layers cumulus cells and 3-4 layers cumulus cells could not be activated. The activation rate of oocytes surrounded by 1-2 layers cumulus cells was 7.6%, significantly lower than the activation rate of the oocytes without cumulus cells (p<0.01).5. The activation rates improved when 6-DMAP or cytochalasin B were added into ionomycin, Ca-A23187, ethanol and DC-pulse respectively, but did not reach the significant level (p>0.05). Cytochalasin B and 6-DMAP inhibited the oocytes to extrude the second probe and make them form diploid. The oocytes treated by Cytochalasin B mainly formed parthenogenetic embryo with 2Pn and 1Pb, and those treated by 6-DMAP mainly formed parthenogenetic embryos with 1Pn and 1Pb.6. The 2~4-cell cleavage rates and beyond 4-cell viability of haploid were similarly to that of diploid. Beyond 8-cell viability of haploid was significantly lower than that of diploid (P<0.05). Haploid did not exceed 16-cell in vitro. The morula rate of diploid was 5.7% in vitro. Developmental speed of parthenogenetic embryos was slower thanthat of natural zygotes in vitro.7. The effect of culture system on parthenogenetic embryos development was bigger than that of natural zygotes in vitro. Parthenogenetic embryos did not overcome 8-cell developmental block cultured in single TCM199 or SOF. The parthenogenetic embryos co-cultured in systems of TCM199 and SOF with granulose cells or ovidu...
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