• Journal of Embryo Transfer
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• v.9 no.3
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• pp.221-227
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• 1994

This study was conducted to examine the condition of in vitro culture system and the viability after embryo transfer of in vitro matured-in vitro fertilized (IVM-IVF) bovine embryos. The in vitro development to the blastocyst stage was enhanced by supplying bovine serum albumin(BSA) to co-culture medium with bovine oviduct epithelial tissue(BOET) compared with that in medium supplemented with fetal bovine serum(FBS) (41.2% vs. 26. 3%, P<0.05). After transfer of IVM-IVF blastocysts into the uterine horn of recipient females (Aberdeen Angus), one was pregnant to term and produced a head of male Korean native calf. These results confirm that the in vitro development of IVM-IVF bovine embryos is affected with different protein source in co-culture with BOET, and IVM-IVF embryos can develop to term after in vitro culture and embryo transfer.

• BMB Reports
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• v.43 no.6
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• pp.389-399
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• 2010

Fertilization is a complex process comprised of numerous steps. During fertilization, two highly specialized and differentiated cells (sperm and egg) fuse and subsequently trigger the development of an embryo from a quiescent, arrested oocyte. Molecular interactions between the sperm and egg are necessary for regulating the developmental potential of an oocyte, and precise coordination and regulation of gene expression and protein function are critical for proper embryonic development. The nematode Caenorhabditis elegans has emerged as a valuable model system for identifying genes involved in fertilization and the oocyte-to-embryo transition as well as for understanding the molecular mechanisms that govern these processes. In this review, we will address current knowledge of the molecular underpinnings of gamete interactions during fertilization and the oocyte-to-embryo transition in C. elegans. We will also compare our knowledge of these processes in C. elegans to what is known about similar processes in mammalian, specifically mouse, model systems.

• Clinical and Experimental Reproductive Medicine
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• v.41 no.1
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• pp.21-28
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• 2014

Objective: To investigate the association of individual follicular fluid (FF) leptin and adiponectin levels with the quality of the corresponding oocyte and embryo. Methods: We prospectively enrolled 67 women who underwent controlled ovarian hyperstimulation with 89 FF samples. FF and the corresponding oocyte was obtained from a single dominant preovulatory follicle at the time of oocyte retrieval. Concentrations of leptin and adiponectin were measured by enzyme-linked immunosorbent assay in an individual follicle. The oocyte quality, fertilization rate, and corresponding embryo development were assessed. Results: The FF level of leptin was significantly associated with body mass index (r=0.334, p<0.01). The FF adiponectin level was significantly higher in the normal fertilization group than the abnormal fertilization group (p=0.009) in the non-obese women. A lower FF leptin level was associated with a trend toward mature oocytes, normal fertilization, and good embryo quality, although these relationships were not statistically significant. The leptin:adiponectin ratio of FF did not differ significantly according to oocyte and embryo quality. The quality of the oocyte and embryo was not associated with the FF leptin level tertile. However, the normal fertilization rate was positively associated with FF adiponectin level tertile. There was a trend towards improved oocytes and normal fertilization rates with the lowest tertile of the FF leptin:adiponectin ratio, but this difference was not statistically significant. Conclusion: Our results suggest that a high FF adiponectin concentration could be a predictor of normal fertilization. However, the FF leptin concentration and leptin:adiponectin ratio is not significantly related to oocyte maturity and corresponding embryo development.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.693-699
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• 2010

Imprinted genes are essential for fetal development, growth regulation, and postnatal behavior. However, little is known about imprinted genes in livestock. We hypothesized that certain putatively imprinted genes affected normal peri-implantation development such as embryo elongation, initial placental development, and preparation of implantation. The objective of the present study was to investigate the mRNA expression patterns of several putatively imprinted genes during the porcine peri-implantation stages from day 6 to day 21 of gestation. Imprinted genes were selected both maternally (Dlk1, IGF2, Ndn, and Sgce) and paternally (IGF2r, H19, Gnas and Xist). Here, we report that the maternally imprinted gene IGF2 was expressed from day 6 (Blastocyst stage), but Dlk1, Ndn, and Sgce were not expressed in this stage. These genes were first expressed between days 12 and day 14. All the maternally imprinted genes studied showed significantly high expression patterns from day 18 of embryo development. In contrast, paternally imprinted genes IGF2r, H19, Gnas, and Xist were first expressed from day 6 of embryo development (BL). Our data demonstrated that the expression of H19 and Gnas genes was significantly increased from day 14 of the embryo developmental stage, while IGF2r and Xist only showed high expression after day 21. This study is the first to show that the putatively imprinted genes were stage-specific during porcine embryonic development. These results demonstrate that the genes studied may exert important effects on embryo implantation and fetal development.

• Journal of Sericultural and Entomological Science
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• v.8
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• pp.35-40
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• 1968

As a result of investigating the change of Ascorbic acid and Lipid which have a relation with metabolism of a silkworm egg in the process of the growth of embryo is silkworm eggs. The following facts have been found 1) Ascorbic acid has gradually increased before the period of the Byong B embryo and it has decreased after period of Byong B embryo. 2) Triglyceride and Total cholesterol has gradually increased before the period of the Byong B embryo and it has decreased after period of the Byong B embryo. 3) Phospholipid has gradually decreased before the period of the Byong A embryo and it increased during the Byong B embryo and decreased again at same stage. It has increased from the head pigment of embryo to hachting. 4) Free Fatty acid decreased during the Byong A embryo stage and increased from the Byong B embryo stage to the Ki A embryo stage and decreased again and increased shortly before the hachting.

• Journal of Animal Reproduction and Biotechnology
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• v.37 no.2
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• pp.80-86
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• 2022

The ability to determine the sex of bovine embryos before the transfer is advantageous in livestock management, especially in dairy production, where female calves are preferred in milk industry. The milk production of female and male cattle benefits both the dairy and beef industries. Pre-implantation sexing of embryos also helps with embryo transfer success. There are two approaches for sexing bovine embryos in farm animals: invasive and non-invasive. A non-invasive method of embryo sexing retains the embryo's autonomy and, as a result, is less likely to impair the embryo's ability to move and implant successfully. There are lists of non-invasive embryo sexing such as; Detection of H-Y antigens, X-linked enzymes, and sexing based on embryo cleavage and development. Since it protects the embryo's autonomy, the non-invasive procedure is considered to be the safest. Invasive methods affect an embryo's integrity and are likely to damage the embryo's chances of successful transformation. There are different types of invasive methods such as polymerase chain reaction, detection of male chromatin Y chromosome-specific DNA probes, Loop-mediated isothermal amplification (LAMP), cytological karyotyping, and immunofluorescence (FISH). The PCR approach is highly sensitive, precise, and effective as compared to invasive methods of farm animal embryonic sexing. Invasive procedures, such as cytological karyotyping, have high accuracy but are impractical in the field due to embryonic effectiveness concerns. This technology can be applicable especially in the dairy and beef industry by producing female and male animals respectively. Enhancing selection accuracy and decreasing the multiple ovulation embryo transfer costs.

• Molecules and Cells
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• v.37 no.2
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• pp.126-132
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• 2014

As a tumor suppressor homologue during mitosis, Chk2 is involved in replication checkpoints, DNA repair, and cell cycle arrest, although its functions during mouse oocyte meiosis and early embryo development remain uncertain. We investigated the functions of Chk2 during mouse oocyte maturation and early embryo development. Chk2 exhibited a dynamic localization pattern; Chk2 expression was restricted to germinal vesicles at the germinal vesicle (GV) stage, was associated with centromeres at pro-metaphase I (Pro-MI), and localized to spindle poles at metaphase I (MI). Disrupting Chk2 activity resulted in cell cycle progression defects. First, inhibitor-treated oocytes were arrested at the GV stage and failed to undergo germinal vesicle breakdown (GVBD); this could be rescued after Chk2 inhibition release. Second, Chk2 inhibition after oocyte GVBD caused MI arrest. Third, the first cleavage of early embryo development was disrupted by Chk2 inhibition. Additionally, in inhibitor-treated oocytes, checkpoint protein Bub3 expression was consistently localized at centromeres at the MI stage, which indicated that the spindle assembly checkpoint (SAC) was activated. Moreover, disrupting Chk2 activity in oocytes caused severe chromosome misalignments and spindle disruption. In inhibitor-treated oocytes, centrosome protein ${\gamma}$-tubulin and Polo-like kinase 1 (Plk1) were dissociated from spindle poles. These results indicated that Chk2 regulated cell cycle progression and spindle assembly during mouse oocyte maturation and early embryo development.

• Journal of Animal Reproduction and Biotechnology
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• v.35 no.1
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• pp.94-101
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• 2020

In the early development of parthenogenetic embryo, cytoplasm and nucleic acid fragmentation may be a cause of lower embryo development. The purpose of this study was to evaluate whether embryonic development and apoptosis factors can be reduced by controlling the in-vitro culture environment by the addition of hormones, pregnancy serum and uterine milk. Our study showed that the activity of Casp-3 increased within the cytoplasm when artificially used hormones to induce the incubation environment, and PCNA's manifestation was low. However, the addition of pregnant serum appeared to lower the Casp-3 activity compared to the other groups. In addition, MMP-9 activity was increased and early embryo development and cytoplasmic fidelity were also increased. Therefore, the results of the present study showed that the use of gestational serum in the development of parthenogenetic embryo inhibit apoptosis and increases cytoplasmic reorganization by natural environmental control in in vitro culture.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2006.10a
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• pp.36-37
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• 2006

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.203-203
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• 2002

The present study was conducted to investigate the potential embryo-fetal toxicity of 2-bromopropane(2-BP) in rats. The test agent was subcutaneously administered to pregnant rats from gestational day 6 to 19 at dose level of 0, 500, 1000, 1500 mg/kg.(omitted)