• Korean Journal of Animal Reproduction
• /
• v.17 no.1
• /
• pp.69-74
• /
• 1993

This study was investigated to examine the effect of conditioned medium from bovine oviductal cell(BOEC) in the co-culture system with BOEC on in vitro development of in vitro produced bovine embryos. Oocyte-cumulus complexes were cultured for 24 hrs in TCM-199 supplemented with 10% fetal calf serum, 1$\mu\textrm{g}$/ml FSH and 21U hCG, 1$\mu\textrm{g}$/ml oestradiol-17$\beta$ at 39$^{\circ}C$ under 5% CO2 in air. In vitro fertilization was performed with epididymal sperm and heparin (10$\mu\textrm{g}$/ml, 15min.) or caffeine(2.5mM)-treated spermatozoa. Oocytes were incubated with 1$\times$106 spermatozoa/ml for 18 hrs and then cultured in various culture system for 7 days. The development rates of 16-cell or blastocyst stages were recorded on 4, 7 days, respectively, after incubating. The proportions ofembryonic development into molulae and blastocysts were higher in cumulus cell co-culture(23.4%) and BOEC co-culture(34.3%) than in M199-FCS(6.1%). Similarily, the development rates into molulae and blastocysts were significantly higher in BOEC-conditioned medium than those in M199-FCS. Therefore, it is suggested that BOEC co-culture and BOEC conditioned medium increase significantly the development of in vitro produced bovine embryos in in vitro system.

• Korean Journal of Animal Reproduction
• /
• v.20 no.4
• /
• pp.473-477
• /
• 1997

This research was performed to investigate the developmental ability of mouse oocytes following cold-culture(4$^{\circ}C$) in vitro. When the oocytes were fertilized after 10 hour cold-culture in D-PBS or Ham's F10 with 0.3% BSA, the cleavage rage of the oocytes was not different in the rate of oocytes fertilized in vitro without cold-culture(126/189, 66.2% vs 88/133, 66.7%) and also the rate of embryos developed to blastocyst did not(123/189, 65.1% vs 82/133). But, when the time of the cold-cultre was extended from 10 to 24 hours, the rate of embryos developed to blastocyst was slightly decreased(73.5% vs 52.2%). However, when the oocytes were cultured for 10 and 24hours at 37$^{\circ}C$, the rate of oocytes developed to blastocyst was significantly decreased than that of oocytes following cold-culture. By the results of this study, it'll be possible to utilize effectively the cold-culture of the oocytes when in vitro fertilization is delayed.

• Korean Journal of Animal Reproduction
• /
• v.4 no.1
• /
• pp.75-82
• /
• 1980

This experiment was carried out to improve a simple and effective procedure of egg transfer which is considered to be the most useful technique for the improvementand proliferation of domestic animals. Several experiment procedures such as superovulation, surgical recovery of ovulated egg, in vitro capacitation of ejaculated spermatozoa, in vitro fertilization and culture of embryo were conducted. The results obtained in this experiment were summarized as follows: 1. In rabbits treated with PMS in combination with estradiol and HCG, 10 to 43 eggs were obtained in one rabbit and the average ovulation number of 20 rabbits was 21 eggs. 2. Six to 24 eggs (average 13 eggs) were recovered from the removed oviducts by the methods of flushing technique and the average recovery rate of 20 rabbits was 61.9 percent. 3. Most rabbit spermatozoa ejaculated by artificial vagina were capacitated in vitro by the culture of the spermatozoa with PBI medium at 37$^{\circ}C$ for 4 hours after removal of seminal plasma. 4. Normal fetilization following in vitro fetilization was observed in 88 (42.7%) of 206 eggs. 5. The number of eggs developed to 2-, 4-, and 8-cell stage following in vitro culture with PBI medium at 37$^{\circ}C$ was 26 (70.3%), 20 (54.1%) and 17 (45.9%) of 37 eggs used for in vitro culture.

• Journal of Embryo Transfer
• /
• v.22 no.4
• /
• pp.251-255
• /
• 2007

This study was carried out to examine on developmental competence of Hanwoo embryos cultured in vitro according to culture conditions and freezing methods. The in vitro developmental competence to blastocyst stage at Day 8 of culture in SOF was significantly (p<0.05) higher than that in CR1aa (30.3% vs. 18.4%). The in vitro developmental rate of morula and blastocysts cultured in group culture was significantly (p<0.05) higher than that in individual culture (41.4% and 36.0% vs. 21.1% and 10.5%, respectively). The cell number of Day 8 blastocysts in group culture was significantly (p<0.05) higher than that in the individual culture ($120.1{\pm}12.8\;vs.\;94.1{\pm}12.1$, respectively). The survival rates of frozen-thawed balstocysts that were exposed in 1.5 M ethylene glycol or 1.5 M ethylene glycol containing 0.1 M sucrose were 77.5% and 78.7%, respectively. The survival rates of blastocysts cultured for 48 h in slow freezing and vitrification was not significantly different (73.3 and 74.0%). In conclusion, in vitro developmental competence of bovine embryos was influenced on the culture medium (SOF) and culture method (Group culture). Survival rate of frozen-thawed of bovine embryos was not influenced on freezing solutions and freezing methods.

• Journal of Embryo Transfer
• /
• v.29 no.1
• /
• pp.1-5
• /
• 2014

Recent 2 decades, including in vitro maturation (IVM), assisted reproductive technologies (ARTs) achieved noteworthy development. However the efficiency of ARTs with in vitro matured oocytes is still lower than that with in vivo oocytes. To overcome those limitations, many researchers attempted to adapt co-culture system during IVM and consequently maturation efficiency has been increased. The beneficial effects of applying co-culture system is contemplated base on communication and interaction between various somatic cells and oocytes, achievement of paracrine factors, and spatial effects of extracellular matrix (ECM) from somatic cell surface. The understanding of co-culture system can provide some information to narrow the gap between in vitro and in vivo. Here we will review current studies about issues for understanding cu-culture system with various somatic cells to improve in vitro maturation microenvironment and provide bird view and strategies for further studies.

• Korean Journal of Animal Reproduction
• /
• v.18 no.2
• /
• pp.113-119
• /
• 1994

To improve nuclear transplantation(NT) efficiency and to produce a large scale genetically identical cloned calves, examined the in vitro development capacity after co-culture of bovine oviductal epithelial cells (BOEC) and granulosa cells in TCM-199 supplemented with 10% fetal calf serum (FCS) with early bovine embryos derived from in vitro matured fertilized(IVM-IVF) oocyte. In addition, the age dependence of IVM oocyte on electro-stimulation and the effective electric voltage on in ivtro development of bovine NT embryos were examined. The results obtained were summerized as follows; 1. The cleavage rates of IVM-IVF bovine embryos in co-culture with bovine oviductal epithelial cells and granulosa cells were not significantly different(P<0.05), but the developmental rate into morula and blastocyst stage were different showing 38.3 and 20.2%, respectively. 2. The activation (82.5%) and development in vitro(8.6%) into later embryo stages of the aging oocytes of 32 hours post-maturation (hpm) were significantly higher than those of 24 hpm at direct current (DC) voltage of 1.5kV/cm, 60$\mu$sec pulse duration and 1 pulse time. 3. The fusion rates of NT eggs of 32 hpm following to different DC voltages from range 0.75 to 1.5kV/cm were not differ, but the developmental rate into morula and blastocyst stages at DC voltages of 0.75 and 1.0kV/cm were higher(11.4 and 12.6%, respectively) than those of 1.5kV/cm(0%). From these results, it can be suggested the optimal culture system for in vitro culture of IVM-IVF bovine embryos is a co-culture system with BOEC in TCM-199 supplemented 10% FCS. The effective time and the DC voltage for activation, electrofusion and in vitro development of NT embryos derived from IVM-IVF bovine embryo are 32hpm and 0.75~1.0kV/cm. But to improve NT efficiency, the advanced research (cell cycle synchronization, micromanipulation, culture system, etc.) is needed.

• Korean Journal of Animal Reproduction
• /
• v.17 no.2
• /
• pp.113-120
• /
• 1993

To provide the optimal culture conditions for the developm,ent of in vit개 produced embryos, we have been investigated various culture media as well as co-cultrue systems using porcine cumulus cells or mouse fetal fibroblast cells. Porcine ovaries were brought to the laboratory from local slaughter house within 1 hour after slaughtering and cumulus oocytes complexes were recovered from antral follicles(3~5mm) with 23 gauge needle. To maturate follicular oocytes, cumulus oocytes complexes were washed three times with TCM-199 containing 25mM HEPES and incubated(39$^{\circ}C$, 5% CO2 in air) in various maturation media for 42 hrs. Ejaculated and liquid storaged boar spermatozoa capacitated with different sperm capacitation methods and media were rpepared for fertilizing of matured follicular oocytes in vitro. Fertilization was performed by adding 5~10${\mu}\ell$ fo capacitated spermatozoa containing 1~5$\times$105 sperm/ml to droplets. Eighteen to twenty-eight hours after sperm insemination, fertilized eggs were washed three times with culture media and transferred to the various culture media, to the culture media with a monolayer of somatic cells. The in vitro development rates of 1-cell embryos cultured with three times with culture media and transferred to the various culture media, to the culture media with a monolayer of somatic cells. The in vitro development rates of 1-cell embryos cultured with three different media, m-KRB, BECM and TCM-HEPES were 0~1.0%, showing extremely lower rates. Especially, most of embryos were observed to arrest the development beyond 4-cell stages. The rates of embryos developed to 2-, 4-, 8-, 16-, 32-cell and morula or blastocyst stage in co-culture with porcine cumulus cells and mouse fetal fibroblast cells were 61.1~67.0%, 59.0~58.0%, 42.5~43.1%, 28.4~30.2% and 20.4~21.0%, respectively. These development rates upto morula or blastocyst stages were significantly higher than those of the embryos cultured in the basic culture medium(P<0.01). These findings suggest that co-culture of in vitro fertilized eggs with porcine cumulus cells or mouse fetal fibroblast cells enhance the development of fertilized eggs to morula or blastocyst stage in vitro.

• Proceedings of the KSAR Conference
• /
• 2000.10a
• /
• pp.9-9
• /
• 2000

The mammalian ovary has a large number of primordial and preantral follicles, which are a potential source of oocytes for the in vitro mass production of embryos. Several in vitro culture systems have been developed to support the growth and development of oocytes from mouse preantral follicles. Under the appropriate condition, meiotically incompetent oocytes from preantral follicles can grow to final size and complete nuclear maturation in vitro. Furthermore, the successful production of live young from in vitro grown and matured oocytes demonstrates that oocytes from preantral follicles are able to acquire full developmental capacity in vitro. However, the efficiency of in vitro production of embryos from mouse preantral follicles is still low. In farm animals as well as human, the growth of oocyte from preantral follicle to the meiotic competence stage has yet to be demonstrate. Therefore, further studies to improve the culture condition or to develope new culture system should be needed in the future. In addition, the visible progress in the establishment of the in vitro culture system for preantral follicles of farm animals and human could help to enlarge the populations of valuable agricultural, phamaceutical product-producing, and endangered animals, and to rescue the oocytes of women about to undergo clinical procedures that jeopardize oocytes.

• Clinical and Experimental Reproductive Medicine
• /
• v.50 no.4
• /
• pp.244-252
• /
• 2023

Objective: We evaluated the efficacy of the newly developed optimized in vitro culture (OIVC) dish for cultivating preimplantation mouse embryos. This dish minimizes the need for mineral oil and incorporates microwells, providing a stable culture environment and enabling independent monitoring of individual embryos. Methods: Mouse pronuclear (PN) zygotes and two-cell-stage embryos were collected at 18 and 46 hours after human chorionic gonadotropin injection, respectively. These were cultured for 120 hours using potassium simplex optimized medium (KSOM) to reach the blastocyst stage. The embryos were randomly allocated into three groups, each cultured in one of three dishes: a 60-mm culture dish, a microdrop dish, and an OIVC dish that we developed. Results: The OIVC dish effectively maintained the osmolarity of the KSOM culture medium over a 5-day period using only 2 mL of mineral oil. This contrasts with the significant osmolarity increase observed in the 60-mm culture dish. Additionally, the OIVC dish exhibited higher blastulation rates from two-cell embryos (100%) relative to the other dish types. Moreover, blastocysts derived from both PN zygotes and two-cell embryos in the OIVC dish group demonstrated significantly elevated mean cell numbers. Conclusion: Use of the OIVC dish markedly increased the number of cells in blastocysts derived from the in vitro culture of preimplantation mouse embryos. The capacity of this dish to maintain medium osmolarity with minimal mineral oil usage represents a breakthrough that may advance embryo culture techniques for various mammals, including human in vitro fertilization and embryo transfer programs.

• Korean Journal of Animal Reproduction
• /
• v.22 no.1
• /
• pp.101-104
• /
• 1998

This study examined the effects of growth factors in TCM199 on bovine 1-cell embryos development in vitro. After 6 day to 11 day in culture, 15.8%(19/120), 15.3%(20/130), 21.8%(35/160), 27.0%(56/207), 26.3%(53/201) and 30.7%(40/130) of the 1-cell embryos developed into expanding blastocysts in su, pp.ementing TCM199 with control, insulin, IGF-I, IGF-II, FGF and EGF, respectively. Hatching rate of 1-cell embryos in su, pp.ementing TCM199 with FGF, EGF and IGF-II were 21.4%(53/247), 20.3%(42/206) and 16.8%(41/243), respectively. The beneficial effect of growth factors on embryo development in vitro could be duplicated. These data indicate that the presence of FGF, EGF or IGF-II in the culture medium is beneficial for embryo development in vitro and accelerate cell differentiation.