Even in an era where 8-meter class telescopes are common, small telescopes are considered very valuable research facilities since they are available for rapid follow-up or long term monitoring observations. To maximize the usefulness of small telescopes in Korea, we established the SomangNet, a network of 0.4{1.0 m class optical telescopes operated by Korean institutions, in 2020. Here, we give an overview of the project, describing the current participating telescopes, its scientic scope and operation mode, and the prospects for future activities. SomangNet currently includes 10 telescopes that are located in Australia, USA, and Chile as well as in Korea. The operation of many of these telescopes currently relies on operators, and we plan to upgrade them for remote or robotic operation. The latest SomangNet science projects include monitoring and follow-up observational studies of galaxies, supernovae, active galactic nuclei, symbiotic stars, solar system objects, neutrino/gravitational-wave sources, and exoplanets.

The reactive oxygen species (ROS) generated during the somatic cell transfer nuclear (SCNT) procedures may cause the mitochondrial dysfunction and DNA damage, which may result in restricts the reprogramming of SCNT embryos and play a key direct role in apoptosis. The present study was conducted to investigate the effect of antioxidant treatment during the SCNT procedures on the inhibition of mitochondria and DNA damages in bovine SCNT embryos. The reconstituted oocytes were treated with antioxidants of 25 μM β-mercaptoethanol (β-ME) or 50 μM vitamin C (Vit. C) during the SCNT procedures. In vitro fertilization (IVF) was performed for controls. Mitochondrial morphology and membrane potential (ΔΨ) were evaluated by staining the embryos with MitoTracker Red or JC-1. Apoptosis was analyzed by Caspase-3 activity assay and TUNEL assay, and DNA fragmentation was measured by comet assay at the zygote stage. Mitochondrial morphology of non-treated SCNT embryos was diffused within cytoplasm without forming clumps, while the IVF embryos and antioxidant treated SCNT embryos were formed clumps. The ΔΨ of β-ME (1.3±0.1, red/green) and Vit. C-treated (1.4±0.2, red/green) SCNT embryos were significantly higher (p<0.05) than that of non-treated SCNT embryos (0.9±0.1, red/ green), which similar to that of IVF embryos (1.3±0.1, red/green). Caspase-3 activity was not difference among the groups. TUNEL assay also revealed that little apoptosis was occurred in SCNT embryos as well as IVF embryos regardless of antioxidant treatment. Comet tail lengths of β-ME and Vit. C-treated SCNT embryos (337.8±23.5 μm and 318.7 ±27.0 μm, respectively) were shorter than that of non-treated SCNT embryos (397.4± 21.4 μm) and similar to IVF embryos (323.3±10.6 μm). These results suggest that antioxidant treatment during SCNT procedures can inhibit the mitochondrial and DNA damages of bovine SCNT embryos.

In ruminants, Interferon-τ (IFN-τ) has the role of recognizing pregnancy signals produced by the embryo and it may have an important role during the luteolysis. Therefore, the purpose of the present study was to investigate the effect of IFN-τ on prostaglandin synthesis, cyclooxygenase-2 (COX-2) gene expression in vitro and secretion of progesterone (P4) in vivo. The epithelial and stromal cells isolated from bovine endometrium were cultured with different doses of IFN-τ (0, 0.02, 0.2 and 2 μg/ml). Human chorionic gonadotropin (hCG, 1.5 IU/ml) was used as a positive control. Prostaglandin E2 and F2α levels in the culture media were analyzed by enzyme immunoassays, and total RNA was extracted from the cells for RT-PCR. P4 concentrations in blood samples were assayed by chemiluminescent immunoassay system. In epithelial cells, COX-2 gene expression was increased in the presence of IFN-τ (p<0.05), but it was not significantly different in all groups of stromal cells except 2 μg/ml IFN-τ group (p<0.05). Although IFN-τ did not affect PGE2 and PGF2α production in epithelial cells, it decreased PGE2 and PGF2α production significantly in stromal cells (p<0.05). In vivo experiment, the P4 concentrations in blood sample was significantly increased after injection of 1 μg/ml IFN-τ. These results indicate that PG production was mediated by COX-2 expression in the stromal cells but it did not affect in the epithelial cells, and suggest that treatment of IFN-τ was to improve the implantation environment of uterine by maintenance of high P4 concentration. * This work was carried out with the support of “Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ907008)” Rural Development Administration, Republic of Korea.

The purpose of this study was to assess sperm quality during in vitro storage of miniature-pig semen in order to determine which extender should be used and how extender can be diluted for in vitro storage of miniature-pig semen. Freshly ejaculated miniature-pig's semen was diluted with same volumes of Beltsville Thawing Solution (BTS), Androhep, Modena, Mulberry III and modified-Modena extenders. Sperm quality was evaluated by examining viability, motility, abnormality, acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining. Sperm motility decreased with storage period prolonged and differences among BTS, Androhep, Modena and Mulberry III were apparent On Day 1, approximately 80% of the sperm were motile, but motility decreased to 40% at Day 7. During the 7 days of storage, sperm survival in modified-Modena B extender was higher than another extenders. However, it was not differ significantly among other extenders. The percentage of F and B patterns were not differ significantly among the extenders. However, F pattern in modified-Modena B extender was slightly higher until 3 days of storage than that of Modena extender, modified-Modena A extender and modified-Modena C extender. The percentage of AR patterns in modified-Modena B extender was slightly lower, but did not differ significantly among other extenders. The results of present study suggest that modified-Modena B was effective as new extender for in vitro storage of miniature-pig semen.

In the present study, we investigated the effects of genotypes on in vitro maturation and fertilization in porcine fresh/frozen-thawed oocytes. The porcine cumulus-oocyte complexes (COCs) were divided into four groups according to whether they were: (1) in vitro matured; (2) cryopreserved and in vitro matured; (3) in vitro fertilized and (4) cryopreserved, and in vitro fertilized. Maturation of porcine COCs was accomplished by incubation in NCSU23 medium. Immature oocytes were cryopreserved by Open Pulled Straws (OPS) method according to Vajta et al., (1998). Oocytes stained by Acetic-Orcein method were observed under the microscope. DNA extracted from the ovaries was analyzed by RAPD (random amplified polymorphic DNA) and SSCP (single strand conformational polymorphisrrt) method. The rates of oocytes maturation and fertilization were significantly high in AA genotype. The results indicated that in vitro maturation and fertilization in porcine fresh/frozen-thawed oocytes may be affected by genotypes in pigs.

The purpose of this study was the analysis of sperm ability in Specific Pathogen Free (SPE) miniature pig for production of bio-organ. The collected semen was diluted with extender and stored at 17℃ for up to 7 days. The semen samples were evaluated at 0, 1, 3, 5, and 7 days of storage for analysis of sperm ability. Sperm ability was evaluated by examining viability, progressive motility, sperm abnormality and intensity of the sperm membrane. Also, the semen was processed according to the convenient freezing method, and frozen-thawed sperm was evaluated by examining viability, capacitation and acrosome reaction using chlortetracycline (CTC) staining. Motility of spermatozoa of SPF miniature pig was significantly (P<0.05) lower on 3 days or later compared to the Duroc, Yorkshire and Landrace in domestic boar. The percentage of abnormal spermatozoa of Landrace were significantly (P<0.05) higher than in SPF miniature pig, Duroc and Yorkshire that had a similar percentage on 5 or 7 days of sperm storage. The percentage of spermatozoa with coiled tail decreased during the storage period but there were no significant difference. On the other hand, viability of frozen-thawed spermatozoa had a significantly (P<0.05) lower in SPF miniature pig than in other domestic boars. CTC patterns had no significant difference, but SPF miniature pig had higher percentage of capacitated spermatozoa and lower percentage of acrosome-reacted it than domestic boars. Therefore, this study suggest that it is necessary to develop the suitable extender and freezing methods methods for the high viable rate and fertilizing ability in vitro.