• Journal of Embryo Transfer
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• v.23 no.4
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• pp.275-281
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• 2008

The ability to preselect the sex of piglets is advantageous in the pig industry. The objective of this study was to examine the feasibility of using intracytoplasmic sperm injection (ICSI) with sorted spermatozoa to produce piglets with a preselected sex. Pig embryos were produced by ICSI of frozen X- and Y-sperm that had been separated by flow cytometry. The developmental competence of the embryos was investigated in vitro and in vivo. The populations of X- and Y-spermatozoa were 52.7% and 47.3%, respectively in our samples. The in vitro development of ICSI embryos was enhanced by longer of in vitro maturation of oocytes ($44{\sim}48\;h$ vs. $40{\sim}43\;h$). Their cleavage ($65{\sim}70%$) and blastocyst formation ($9{\sim}12%$) rates were not significantly different between male and female ICSI embryos, or between sorted and unsorted sperm-derived embryos. One pregnancy was established in a recipient that was transferred with 110 female ICSI embryos, but the pregnancy was terminated on Day 89 of gestation. Our results suggest that the separation X- and Y-spermatozoa by flow cytometric sorting can be a useful tool in combination with ICSI for the production of pig embryos and piglets of preselected sex.

• Korean Journal of Animal Reproduction
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• v.18 no.1
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• pp.7-13
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• 1994

To verify in vivo viability of IVF-derived bovine embryos, morula and blastocysts that developed from in vitro matured and fertilized ova were transferred to the uteri of recipient cows and normal calves were produced. To produce IVF-derived bovine morula or blastocysts, ova matured and fertilized in vitro were cultured in culture medium for 7~8 days at 39$^{\circ}C$ under the humicified atmosphere of 5% CO2. Two different culture systems, a co-culture system with TCM-199 and bovine epithelial cells (BOEC) and CR1aa without somatic cell support, were compared. Cleavage rates to 2~8 cell stage and developmental rates of IVF-derived bovine embryos to blastocyst stage were not different between co-culture system (51.3 and 14.0%) and CR1aa medium (60.4 and 22.1%), respectively. Embryos were classified into three grades by embryo quality and then one or two embryos in higher quality(A and B grades) were transferred to the uterus of recipients. In this study Korean Native calf was first born after transfer of IVF-derived embryos. Total four live calves were normally developed to term from IVF-derived bovine blastocysts and one female fetus was still-born approximatedly 8 months of gestation, but there was no pregnancy after transfer of morula. Therefore, normal calves could be produced after transfer of IVF-derived bovine embryos cultured in CR1aa medium without somatic cell support. In addition, our results suggest that in transfer of IVF-derived bovine embryos blastocyst stage is better than morula.

• Proceedings of the KSAR Conference
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• 2001.10a
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• pp.44-46
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• 2001

In vitro produced (IVP) embryos produced by in vitro fertilization (IVF) often exhibit wide variations in developmental competence and viability, considerably more than are exhibited by embryos that develop in vivo. These anomalies in IVP embryos may be due to heterogeneity of oocyte quality, suboptimal culture conditions, disturbances in gene expression, or most likely a combination of these factors (Ho et al., 1994; Roth et al., 1994; McKiernan and Bavister, 1998; Hasler, 1998; Schramm and Bavister, 1999; Doherty et al., 2000; Hyttel et al., 2000; Niemann and Wrenzycki, 2000; Wrenzycki et al., 2001). In research studies or in clinical applications with domesticated animals, cats, non-human primates and humans, oocytes used for IVF are usually collected from a heterogeneous cohort of ovarian follicles that include oocytes which normally might not be ovulated and/or are deficient in developmental competence. (omitted)

• Journal of Embryo Transfer
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• v.24 no.4
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• pp.253-257
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• 2009

To enhance the embryo preservation technology and better application of embryo transfer technique to the field (dairy science or animal reproduction. etc.), we examined the viabilities of bovine embryos produced in vitro and in vivo after cryopreservation according to their developmental stage and thawing temperature. Bovine embryos from in vivo/vitro fertilization (Hanwoo) were examined at day 7, 8, and 9. Survival rates and total cell numbers of in vivo fertilized embryos were as follows: morulae 68.8% and $67\;{\pm}\;6.0$; blastocysts 80.5% and $120\;{\pm}\;10$; expanded blastocysts 77.4% and $138\;{\pm}\;9.7$, respectively. Rates of embryo development for blastocysts and expanded blastocysts after thawing were significantly higher than that of morula stage embryos (p<0.05). While survival rates of in vitro fertilized embryos according to developmental stage showed no significant difference among groups (morula 67.9%; blastocyst 74.3%; and expanded blastocyst 79.4%), total cell numbers were significantly lower than those of other groups (morula $64\;{\pm}\;5.9$; blastocyst $116\;{\pm}\;8.7$; and expanded blastocyst $135\;{\pm}\;9.1$) For the viability according to thawing temperature, survival rate was higher in $37^{\circ}C$.

• Journal of Embryo Transfer
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• v.11 no.3
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• pp.241-248
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• 1996

This study was conducted to improve the production efficiency of in vitro produced (IVP) embryos in Korean Native cows. The optimal conditions and procedures for in vitro maturation(IVM), in vitro fertilization(IVF) and in vitro culture(IVC) of bovine follicular oocytes and IVP embryos were evaluated. Immature follicular oocytes were collected fiom the follicles of bovine ovaries obtained from abattoirs. The oocytes of Grade I and II for IVM were cocultured with monolayered bovine oviductal epithelial cells(BOEG) or granulosa cells in TCM-199 solution supplemented with follicle stimulating hormone, lutenizing hormone, estradiol-17$\beta$ and heat inactivated fetal calf serum at 39$^{\circ}C$ under 5% $CO_2$ in air for 14 to 24 hours. Most of the oocytes(93%) matured to metaphase II in 24 hours. The cocultured IVM oocytes were fertilized in vitro at significantly(P<0.05) higher rate with BOEC(83.8%) and with granulosa cells(84.6%) than the non-cocultured IVM oocytes(73.6%). The IVM-IVF embryos developed to morula and blastocyst at significantly(P<0.05) higher rate in coculture with BOEC(41.2%) than with granulosa cells(23.1%) or conditioned medium(23.4%).

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.47-47
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• 2003

The present study was conducted to determine the expression of the antioxidant enzyme(CuZn-SOD, Mn-SOD and GPX and apoptosis gene(caspase-3) for in vitro culture in in vitro maturation and in vitro fertilization(IVM/IVF) embryos in porcine. Porcine embryos derived from IVM/IVF were cultured in NCSU23 medium under 5% $CO_2$ in air at 38.5$^{\circ}C$. The patterns of gene expression for several antioxidant enzyme and apoptosis genes during preimplantion porcine embryo development were examined by the modified semi-quantitative single cell reverse transcriptase- polymerase chain reaction (RT-PCR). Preimplantation porcine embryos produced by IVM/IVF have expressed mRNAs for CuZn-SOD and GPX, whereas transcripts for Mn-SOD have not detected at any developmental stages. Expression of caspase-3 mRNA was detected at 2 cell, 8 cell, 16 cell and morula stages. The fas ligand transcripts were detected in porcine blastocyst. These results suggest that various antioxidant enzymes and apoptosis genes play crucial roles in in vitro culture of porcine IVM/IVF embryos.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.9
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• pp.1342-1351
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• 2001

Over the years, the embryo transfer industry has grown from the simple collection & transfer of embryos into an advanced field of embryo biotechnology. Currently a large demand exists for bovine oocytes and early embryos in both research and commercial settings. Bovine embryos can now be produced in-vitro. Primary oocytes collected from antral follicles of abattoir - obtained ovaries can be induced to undergo the maturation process. In-vitor maturation system, however must ensure that the resulting oocyte is capable of undergoing normal fertilization and yields a zygote competent of developing to term after embryo transfer. Sperm preparation for IVF has improved with the use of heparine. The use of co-culture system has proved beneficial in circumventing the developmental block in IVM/IVF bovine embryos.

• Journal of Embryo Transfer
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• v.12 no.1
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• pp.67-74
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• 1997

This study was carried out to increase the viability of bovine frozen4hawed in vitro produced (IVP) embryos and pregnancy rate by direct transfer method. Cumulus-oocyte complexes were aspirated from excised Hanwoo ovaries and matured in TGM 199 for 20~22 hours at 38.5$^{\circ}C$ in 2% $CO_2$ in air. Matured oocytes were fertilized with capacitated sperm for 6 hours and then co-cultured with cumulus cells for 9 days. 63% of the oocytes cultured was deaved and 29% out of them developed into blastocysts. Good or excellent grade of blastocysts on D 7 or 8 were frozen with 1.8M ethylene glycol as a cryoprotectant for direct transfer. Frozen embryos were thawed at 2$0^{\circ}C$ water for 10 sec following 4~5 second in air. For the survival assay of frozen4hawed lVP blastocysts, they were cultured in TCM 199 supplemented with 100$\mu$M $\beta$-mercaptoethanol and 20% FCS for 72 hours. The percentage of embryos developed to re-expanded or hatched after 72 hours culture was 95. 5 and 77.3%, respectively. When frozen-thawed Ivp embryos were transferred to 43 synchronized recipients by direct transfer method, eighteen recipients (41.8%) was pregnant. The highest pregnant was in naturafly synchronized recipients (71.4%), but induced estrus by using PRID(29.2%) and PGF$_2$$\alpha$(20.0%) was showed lower pregnancy rate. The pregnancy rate was higher in day 7 blastocysts(56.0%) than day 8 blastocysts(22.2%). (Key words: in vitro produced, blastocyst, frozen-thawed, direct transfer)

• Journal of Embryo Transfer
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• v.10 no.1
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• pp.65-72
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• 1995

The purposes of this study were to produce cloned rabbit embryos and offsprings by nuclear transplantation(NT) using in vitro matured oocytes as nuclear recipient cytoplasm and to determine the effect of frozen nuclei donor embryos on the production efficiency of cloned embryos. The 8cell embryos were collected from the mated does by flushing oviducts with Dulbecco's phosphate buffered saline containing 10% fetal calf serum(FCS) at 40 hours after hGG injection. A portion of collected embryos were preserved at 4$^{\circ}C$ for 24 hours and a portion of them were frozen by vitrification method. The embryos used for donor nuclei were synchronized in the phase of Gi /S transition. The in vitro matured oocytes were used as recipient cytoplasm following removing the nucleus and the first polar body. The synchronized blastomeres from fresh, cooled or frozen embryos were injected into the enucleated oocytes by micromanipulation and were electrofused by electrical stimulation of three pulses for 60 $\mu$sec at 1.0 W /cm in 0.28 M mannitol solution. The fused oocytes were co-cultured with a monolayer of rabbit oviductal epithelial cells in M-199 solution containing 10% FCS for 120 hours at 39$^{\circ}C$ in a 5% $CO_2$incubator. Following in vitro culture of the NT embryos to blastocyst stage, they were stained with Hoechst 33342 dye for counting the number of blastomeres by fluorescence microscopy. The nuclear transplant embryos developed in vitro to 2- to 4-cell stage were transferred into the oviducts of synchronized recipient does. The results obtained were summarized as follows: 1. The fusion rates of the blastomeres from fresh, cooled and frozen embryos with the in vitro matured and enucleated oocytes were 100, 95.8 and 64, 3%, respectively. 2. Development in vitro to blastocyst was significantly(p<0.05) different between the cloned embryos with the blastomeres from fresh, cooled or frozen embryos as 39.0, 20. 9 and 15.7%, respectively. 3. The mean numbers of cell cycle per day during in vitro culture of cloned embryos blastomeres from fresh, cooled or frozen embryos was 1.31, 1.29 and 1.16, respectively. 4. A total of 77 nuclear transplant embryos were transferred into 6 recipient does, of which two offsprings were produced from a foster mother 31 days after embryo transfer.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.8
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• pp.1188-1195
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• 2001

A tetraparental chimeric bull was successfully produced by aggregating bovine IVF embryos of F1 (female Holstein${\times}$male Japanese Black) and F1(female Japanese Brown${\times}$male Limousin) and culturing in vitro without the zona pellucida at Yamaguchi Research Station in Japan. In the microsatellite genotyping, 12% (28/228) microsatellite primer sets ware potentially useful for this parentage analysis in the chimeric bull, 78.6% (22/28) of microsatellite present in the chimeric bull were uniquely contributed from the Japanese Black and 21.4% (6/28) from Limousin. This chimeric bull semen was used in producing IVF embryos. The chromosome preparations were made from peripheral lymphocytes. Based on chromosome analysis the Chimera had apparently normal chromosomes (29 acrocentric pairs, one large sub metacentric X chromosome and one small sub metacentric Y chromosome). The proportion of acrosome reacted spermatozoa after 1 h of incubation was higher (p<0.01) with the Chimera than with the Holstein and in Japanese Brown bulls. But did not differ from Japanese Black and Limousin bull sperm. Fertilization rates observed after 5 h of sperm-oocyte incubation with Chimera sperm were higher (p<0.05) than with Japanese Brown and (p<0.01) than with Holstein sperm, but did not differ from Japanese Black and Limousin sperm. The cleavage rates of IVF oocytes inseminated with Chimera sperm were also higher (p<0.001) compared with Holstein, (p<0.01) Japanese Brown and (p<0.05) Limousin, but did not differ from Japanese Black sperm. The blastocyst rates of IVM oocytes inseminated with sperm were higher (p<0.05) than in Limousin, Japanese Brown and Holstein, but did not differ from Japanese Black. Chimeric cattles were produced by aggregation of parthenogenetic (Japanese Brown) and in vitro fertilized (Holstein) bovine embryos at the Yamaguchi Research Station in Japan and by aggregation of parthenogenetic (Red Angus) and in vitro fertilized (Holstein) embryos at the St. Gabriel Research Station in Louisiana. The aggregation rate of the reconstructed demi-embryos cultured in vitro without agar embedding was significantly lower than with agar embedding. The aggregation was also lower when the aggregation resulted from a whole parthenogenetic and IVF-derieved embryos cultured without agar than when cultured with agar. The development rate to blastocysts, however, was not different among the treatment. To verify parthenogenetic and the cells derieved from the male IVF embryos in blastocyst formation, 51 embryos were karyotyped, resulting in 27 embryos having both XX and XY chromosome plates in the same sample, 14 embryos with XY and 10 embryos with XX. The viability and the percentage of zonafree chimeric embryos at 24 h following cryopreservation in EG plus T with 10% PVP were significantly greater than those cryopreserved without PVP. Pregnancies were diagnosed in both stations after the transfer of chimeric blastocysts. Twin male and single chimeric calves were delivered at the Yamaguchi station, with each having both XX and XY chromosomes detected. Three pregnancies resulted from the transfer of 40 chimeric embryos at the Louisiana station. Two pregnancies were Jost prior to 4 months and one phenotypically chimeric viable male born.