• 한국수정란이식학회지
• /
• 제14권1호
• /
• pp.23-29
• /
• 1999

The objectives of the study were to establish sperm separation method and duration of insemination for bovine IVF. Oocytes from slaughterhouse ovaries were matured and fertilized using general protocol. After 18 or 42 h of insemination, six to ten embryos were placed into a 30${mu}ell$ drop of each medium, and the embryos were examined 7~10d post in semination without medium renewal. First, we compared Percoll gradient will swim-up technique for sperm separation. There was no difference in cleavage rates between them, but the development rates over morula stage of oocytes fertilized with sperm separated by Percoll gradient was significantly higher than that sperm selected by swim-up technique (p<0.05). Second, we evaluated development of bovine embryos derived from the IVF procedure with different durations(18 vs 42 h) of fertilization. There was also no difference in cleavage rates, but the development to blastocyst stage of oocytes exposed in cleavage rates, but the development to blastocyst stage of oocytes exposed to sperm for 42 h was significantly higher than that exposed for 18 h (p<0.05). In conclusion, Percoll gradient can be used for sperm selecton, improving of embryonic development. Also, 42h of IVF may improve the development of bovine embryos.

• 한국동물번식학회:학술대회논문집
• /
• 한국동물번식학회 2001년도 춘계학술발표대회
• /
• pp.11-11
• /
• 2001

In this study, we examined the developmental potential of reconstructed bovine embryos and the fate of donor mitochondria during their preimplantation development after nuclear transfer. Isolated cumulus cells were used as donor cells in nuclear transfer. Cumulus cells labelled with MitoTracker Green FM fluorochrome were injected into enucleated bovine MII oocytes and cultured in vitro. MitoTracker labelling on donor cells did not have a detrimental effect on blastocyst formation following nuclear transfer. Cleavage rate was about 69%(56/81) and blastocyst formation rate was 6.2% (5/81) at 7 days after nuclear transfer. The labelled mitochondria dispersed to the cytoplasm and became distributed among blastomeres and could be identified up to the 8- to 15-cell stages. Small patches of mitochondria were detected in some 8- to 15-cell stage embryos (5/20). However, donor mitochondria were not detected in embryos at the 16-cell stage and subsequent developmental stages. In the control group, mitochondria could be identified in arrested 1-cell embryos up to 7 days after nuclear transfer These results suggest that donor mitochondria disappear from recipient cytoplasm before 16-cell stage following nuclear transfer in reconstructed bovine embryos.

• 한국수정란이식학회지
• /
• 제14권2호
• /
• pp.93-97
• /
• 1999

The development potential of bovine somatic cells was evaluated using nuclear transfer. A single donor cell derived from fetus of HanWoo(Korean Native Cattle) was selected and deposited into perivitelline space of each enucleated oocyte before electrical fusion and activation. Nuclei of donor cells starved for 7 days (37%) tended to support the development of reconstitute embryo the blastocyst stage better than those of donor cells starved 3, 14 and 30 days. The cleavage rate was significantly lower(P<0.05) in reconstitute embryos derived from large size donor cells(51.2%), than those from small medium size donor cells(76.6 and 73.5, respectively). The developmental rate to blastocyst of reconstructed embryos from medium size donor cells was higher than those from small and medium size donor cells. This study demonstrates that an appropriate culture period for induction into quiescent stage and the size of donor cells effect on the efficiency of nuclear transfer using cultured bovine cells.

• 한국가축번식학회지
• /
• 제20권3호
• /
• pp.279-288
• /
• 1996

본 연구는 EGF가 체외성숙과 수정에 의해 생산된 소 수정란의 발달과 inner cell mass (ICM)와 trophectoderm (TE) 세포수에 미치는 영향 및 공동배양시의 첨가효가를 조사하고 그와 더불어 간적면역 형광법을 이용하여 EGF-R 단백의 발현 유무를 조사하기 위해 실시하였다. 그 결과를 요약하면 다음과 같다. EGF 1, 10, 100 ng/ml의 농도로 처리되었던 4-세포기와 8-세포기 배는 대조군에 비하여 유의차는 인정되지 않았으나 양호한 배반포기 배 발달과 ICM과 TE 세포수 증가 양상을 나타내었다. 특히, 발달단계에 따른 EGF (10ng/ml) 효과를 조사하였던 바, 8-세포기 이후 배에서 대조군에 비하여 배반포기까지 유의한 배 발달을 유도하는 것을 확인할 수 있었지만 (p<0.05), ICM과 TE 세포수 증가에는 유의한 영향을 미치지 못하는 것을 알 수 있었다. 또한, 간접 면역 형광에 의한 EGF-R의 발현 유무를 조사한 결과, EGF-R는 4-세포기 이후에 발현되며 그 강도는 발달단계가 진행되면서 다양하게 나타난다는 것을 알 수 있었다. 한편, 수정란과 난구세포 공동배양 군은 EGF의 첨가 유무에 상관없이 대조군에 비하여 유의한 배 발달과 총세포수의 증가를 나타내며, 공동배양군에 대한 EGF 첨가는 수정란과 난구세포와의 공동배양 효과를 증진시키는 것으로 나타났다. 따라서, EGF는 착상전 소 수정란의 4-세포기 이후에 발현디는 EGF-R에 반응하여 배 발달을 유기하고, 공동배양시의 배 발달에 유용한 물질형성을 촉진시키지만, 배반포기 배의 ICM과 TE 세포수 증가에는 유의한 영향을 나타내지 못한다는 것을 알 수 있었다.

• 한국수정란이식학회지
• /
• 제9권1호
• /
• pp.7-14
• /
• 1994

The present experiments on cryopreservation were designed to examine the effects of solution toxicity, equilibration time and cell stages on the post-thaw survival of bovine IVF embryos. The oocytes were matured in vitro(IVM) for 24 hrs. in TCM-199 supplemented with 35 $\mu$g /ml FSH, 10 $\mu$g /ml LH, 1 $\mu$g /ml estradiol-17$\beta$ and granulosa cells at 39$^{\circ}C$ under 5% $CO_2$ in air. They were fertilized in vitro(IVF) by epididymal spermatozoa treated with heparin for 24 hrs., and then the zygotes were co-cultured in vitro(IVC) with bovine oviductal epithelial cells for 7 to 9 days. The bovine IVF embryos were exposed to the EFS solution in one step at room temperature, kept in the EFS solution during different period for toxicity test, vitrified in liquid nitrogen, and thawed rapidly. 1. after the bovine blastocysts were exposed to EFS solution for 2 min. at room temperature and then they were washed in 0.5 M sucrose solution and TCM-199, they were cultured to examined cryoprotectant induced injury during exposure, Most of the embryos(95.0%) developed to reexpanded blastocoels. However, when the exposure time was extended to 5 and 10 min, these development rates dropped dramatically in 5 min. (69.5%) and 10 min. (47.4%), respectively, 2. When the bovine IVF embryos were vitrified in EFS solution after the equilibration for 1 and 2 min. exposure, The embryos to have reexpanded blastocoels following thawing, washing and culture processes were found to he 82.6 and 73.9%, respectively. However, when the exposure time was extended to 3 min, this survival rate dropped to 18.2%. The optimal time for equilibration of bovine IVF blastocysts in EFS solution seemed to he 1~2 min. 3. When the bovine IVF embryos were equilibrated for 1 min. the significantly (P<0. 05) higher post-thaw survival rates were obtained from the embryos of blastocyst stage(81.3%) than morulae stage(5. 1%). The optimal cell stage for viterification with EFS solution proven to he blastocyst stage in bovine IVF embryos. 4. The number of blastomeres of blastocyst stage was examined with nuclear staining with Hoechst 33342 during 7 to 9 days post-insemination. The cell counts of frozen bovine IVF embryos were found significantly(P$\geq$7.5 and those of the fresh embryos 76.6$\geq$7. 1, which were cultured in the sarne period and conditions as frozen embryos.

• 한국수정란이식학회지
• /
• 제23권4호
• /
• pp.263-267
• /
• 2008

The purpose of this study was to determine toxic effect of sucrose and trehalose prior to cryopreservation on nuclear maturation and embryonic development in immature bovine oocytes. All cryoprotectant was prepared in tissue culture medium 199-HEPES (TCM 199-HEPES) with 10% fetal bovine serum (FBS). Immature oocytes were exposed to 1.2M ethylene glycol (EG) and 0.1M sucrose or 1.2M EG and 0.1M trehalose for 3 min and then were exposed to 3.2 M EG and 0.25 M sucrose or 3.2 M EG and 0.25 M trehalose for 1 min. Oocytes treated with cryoprotectants were exposed to 0.25 M sucrose or 0.25 M trehalose for 5 min and then 0.1 M sucrose or 0.1 M trehalose for 5 min. Depending on type of sugar added to cryopreservation solution, oocytes were allocated to sucrose group and trehalose group, respectively. Oocytes exposed to TCM 199-HEPES with 10% FBS were considered as control. Oocytes were cultured in TCM 199 supplemented with 10% FBS, 5 ng/ml epidermal growth factor, 0.01 IU/ml luteinizing hormone, and $1\;{\mu}g/ml$ estradiol for 24 h in $39^{\circ}C$, 5% $CO_2$. Nuclear maturation was assessed by staining oocytes with 1% aceto-orcein. Oocytes were fertilized in vitro and were cultured in TCM 199 supplemented with 10% FBS, 5 mM sodium pyruvate, and antibiotics in $39^{\circ}C$, 5% $CO_2$. The rates of cleavage and blastocyst, and cell number in blastocyst were assessed. Metaphase II rates were not different among experimental groups regardless of type of sugar. The cleavage rate of trehalose group (73.3%) was significantly higher (p<0.05) than those of sucrose group (62.8%) and control group (60.8%). The blastocyst rate was significantly higher in trehalose group (p<0.05). Mean cell number in blastocyst were not different among experimental groups, although cell number of blastocyst in trehalose group was significantly higher on day 7 (p<0.05). In conclusion, sucrose and trehalose were not toxic to immature bovine oocytes prior to cryopreservation. In particular, trehalose was more effective on embryonic development.

• 한국가축번식학회지
• /
• 제25권2호
• /
• pp.131-138
• /
• 2001

생쥐 초기배의 배반포 발달율이 BSA첨가 배양액에 Barodon-FX(equation omitted) 첨가로 증가되지 않았으나 PVP 첨가 배양액에 0.25% 첨가에서는 부화배반포 발달율이 54.7%로 대조구(32.5%)보다 크게 향상 되었다(P ＜0.05). 1∼2% Barodon 첨가는 배발달을 월등히 저하시켰다. Barodon 첨가에 따른 체세포 증식율은 BOEC와 GC의 경우 0.25∼0.5%에서 대조구보다 각각 24∼40%와 17∼22%더 크게 증가되었다(P＜0.05). 그러나 GC와 CC에서는 1%이상 첨가시 세포증식이 크게 억제되었다(P ＜0.05). Barodon의 효과는 체세포간에 큰 차이가 있었다. 소 초기배에서 상실배이상의 배발달율은 BOEC와 GC 공배양조건에서 Barodon 0.5% 첨가에서 대조구보다 크게 향상되었다(P＜0.05). 그러나 다른 처리 수준에서는 배 발달율이 대조구와 차이가 없었다. 결론적으로 Barodon의 세포증식효과는 세포종류에 따라 차이가 많았으며 0.5% 수준의 첨가는 소 초기배의 배반포발달율을 향상시킬 수 있었다.

• 한국동물번식학회:학술대회논문집
• /
• 한국동물번식학회 2001년도 춘계학술발표대회
• /
• pp.28-28
• /
• 2001

The objective of this study was to the effect on subsequent development of EGF present in defined medium during bovine 1)oocyte maturation or 2)embryo culture. The presence of EGF during IVM, irrespective of concentration(1, 10, 100ng/$m\ell$), stimulated cumulus expansion and significantly increased the proportion of oocytes attaining metaphaseII, the rate of cleavage, and develop to blastocyst. 1. In the group of EGF-added medium(1, 10, 100ng/$m\ell$), nuclear maturation rate for in vitro maturation was 91% to 92% but was not significantly higher than control group(87%). 2. For in vitro maturation, in the group of EGF-added medium(1, 10, 100ng/$m\ell$)the rate of cumulus cell expansion degree 2 ranged from 81% to 87%, which was significantly higher than the control group(medium with EGF not added). The rate of in vitro fertilization, developing to 2-to 4- cell stage, was 76% to 80%, which was also significantly higher(p<0.05)than control group(62%). 3. For in vitro maturation, in the group of EGF added in medium(1, 10, 100ng/$m\ell$)the development rate to blastocyst was 24.3% to 27%, which was significantly higher than control group(13.7%). The total cleavage rate in the group of EGF-added medium was 77% to 82%, which was higher than control group. 4. The development rate to blastocyst for 6 days of cultivation and the hatching blastocyst were 30.6% and 59.1%, respectively, in the group of 100ng/$m\ell$ of EGF, which were significantly higher(p<0.05)than control group(14.0% and 24%, respectively), The numbers of cells in blastocyst were 140.2 and 148, respectively, in 10ng/$m\ell$ and 100ng/$m\ell$ of EGF-added medium, which were higher than 108.5 in control group. 5. The development rate of in vitro fertilized embryos to blastocyst in 10ng/$m\ell$ of EGF-added medium co-cultured with somatic cell was 28%, which was significantly higher(p<0.05)than control group(11.8%). The numbers of cells in blastocyst were 141.6 for EGF-added medium and 145 for EGF+co-culture group, which were higher than control(101.6)and medium co-cultured with somatic cells(110.6). These results showed that in vitro maturation and fertilization, EGF was found a significant effect of increase of development rate to blastocyst and cell number.

• Asian-Australasian Journal of Animal Sciences
• /
• 제16권1호
• /
• pp.23-28
• /
• 2003

The present study was undertaken to investigate the effects of PVP concentration and exposure temperature to vitrification solution on the post-thaw survival, in vitro maturation and development of immature bovine oocytes (germinal vesicle stage). The vitrification solution (VS) consisted of 40% ethylene glycol (EG)+0.5 M sucrose (S)+10% FBS. PVP was added to VS: 0%, 5% or 10%. The cumulus-oocyte complexes (COCs) were diluted in VS as one step, after 2 min the COCs were loaded in straw and vitrified by direct immersion into liquid nitrogen. For thawing, the straws were plunged into $30^{\circ}C$ water bath for 10s. After thawing, the oocytes were diluted in 0.5 M (in DPBS with 10% FBS) sucrose solution for 5 min. The survival rate (FDA-test and trypan blue) of immature bovine oocytes was measured. The survival rate was higher in 5% PVP (91.5%) than in 0% (64.2%) or in 10% PVP (79.7%). The proportion of metaphase II formation was 69.35% in control (no vitrified COCs), 9.3% in 40% EG+0.5 M S+0% PVP and 21.05% in 40% EG+0.5 M S+5% PVP (p<0.05). The effect of room temperature ($25^{\circ}C$ for 10 min) and cold temperature ($4^{\circ}C$ for 10 min) on COCs were determined in this study. After IVF, the cleavage and blastocysts rate of oocytes exposed to room temperature and cold temperature in VS+5% PVP was significantly different (2 cell: 63.20% vs 37.97%, blastocysts: 18.40% vs 2.53%). The cleavage rates of frozen-thawed oocytes were 20.53% with PVP and 22.13% without PVP (p>0.05). Two out of 151 oocytes (1.32%) developed to blastocyst stage after frozen-thawed with 5% PVP (p>0.05). Development of oocytes after frozen-thawing to the 2 cell were not significantly affected with or without PVP following IVF. However, the vitrification of immature bovine oocytes with PVP maintained the ability to develop to the blastocyst stage after IVM-IVF and IVC, while no blastocysts were obtained from oocytes vitrified without PVP. These results suggested that PVP has a protective role for vitrification of immature bovine oocytes as far as survival is concerned, however, the protection was not sufficient enough to support blastocyst formation.

• 한국가축번식학회지
• /
• 제19권3호
• /
• pp.191-195
• /
• 1995

본 연구는 체외성숙한 소의 난포란을 ethanol로 활성화시켰을 때 cytochalasin에 노출한 시간과 농도가 난포란의 배반포단계로의 발달에 미치는 영향을 검토하였다. 30시간 체외성숙시킨 소 난포란을 7% ethanol이 든 Dulbecco's phosphate buffered saline에 7분간 노출시켜 활성화를 시킨 후, cytochalasin D가 첨가된 TCM＋199＋10% fetal calf serum에서 일정시간 배양하여 세포주기를 억제시켰다. 난포란을 활성화시킨 후, 0, 5, 10 그리고 15시간 cytochalasin D(5$\mu\textrm{g}$/ml)에 노출시켰을 때, 5시간에서 가장 높은 배반포(16%), 팽윤배반포(13%), 부화배반포(7%)로의 발달률을 보였다. 또한 cytochalasin D 0, 2.5, 5 그리고 7.5$\mu\textrm{g}$/ml에서 7시간 노출시켰을 때, 2.5$\mu\textrm{g}$/ml에서 가장 높은 배반포(13%), 팽윤배반포(7%), 부화배반포(4%)로의 발달률을 보였다. 결론적으로 cytochalasin D는 난폰란의 단위발생에 중요한 역할을 하며, 성숙한 난포란은 cytochalasin D 2.5$\mu\textrm{g}$/ml에서 5시간 노출하였을 때 가장 높은 배반포로의 발달률을 보여주었다.