• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.3
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• pp.170-176
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• 1993

The yield, viability and continuous culture of isolated Italian ryegrass protoplasts were investigated. The effects of cold treatment (4^{\circ}C.$) for 7 days and basic LS medium supplemented with 5mg/l $AgNO_3$ showed effectively on embryogenic callus induction and regeneration responses of immature and mature embryos or young inflorescences subcultured every 4 weeks on basic medium. The optimum combinations of growth regulator on the regeneration responses was 0.2mg/l BAP and 2mg/l 2, 4-D. Calli induced inflorescences were suspended in its liquid medium for 5 days before enzyme treatment. Maximum protoplast yield and viability were obtained after digestion in enzyme solution contained 4% cellulase R10. 2% macerozyme and 2% pectinase in 0.6M mannitol. Cell division and microcalli development were observed in isolated protoplasts cultured in agarose culture of KM8P medium.

• Journal of Veterinary Science
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• v.21 no.3
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• pp.48.1-48.18
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• 2020

Background: Mature oocytes at the metaphase II status (MII-stage oocytes) played an important role in assisted reproductive technology in non-human primates. Objectives: In order to improve the proportion of MII-stage oocytes retrieval, three different superovulation protocols were performed on 24 female cynomolgus monkeys. Methods: All the monkeys received once-daily injection of follicle-stimulating hormone (25 international unit [IU]) on day 3 of the menstruation, 3-day intervals, twice daily for 8-12 days until the time of human chorionic gonadotropin (1,500 IU) injection, on the 14-17th day of menstruation collecting oocytes. The difference between protocol I and protocol II was that 0.1 mg the gonadotropin-releasing hormone agonist was injected on day 1 of the menstruation, while the difference between personalized superovulation protocol and protocol II was that oocytes could be collected on the 14-17th day of menstrual cycle according to the length of each monkey. Results: The total number of oocytes harvested using the personalized superovulation protocol was much higher than that using protocol I (p < 0.05), and the proportion of MII-stage oocytes was significantly greater than that from either superovulation protocol I or II (p < 0.001 and p < 0.01 respectively), while the proportion of immature oocytes at the germinal vesicle was less than that from superovulation protocol I (p < 0.05). Conclusions: The personalized superovulation protocol could increase the rate of MII-stage oocytes acquired, and successfully develop into embryos after intracytoplasmic sperm injection, and eventually generated fetus.

• Korean Journal of Plant Tissue Culture
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• v.24 no.3
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• pp.129-135
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• 1997

Morphogenetic responses were investigated by culturing embryo and leaf explants of Korean wild type tea plant, Camellia sinensis (L.) O. Kuntze. Induction of direct somatic embryogenesis as well as adventitious and/or axillary shoots was obtained from mature zygotic embryo cultures on Murashige and Skoog (MS) basal medium having 5 to $20\mu\textrm{M}$cytokinin a lone. Morphogenetic response was decreased dramatically by the addition of auxins tested. One hundred percent of induced and isolated shoots formed roots after four weeks of culture on half-strength MS or quarter-strength Schenk and Hildebrandt (SH) media supplemented with $10\mu\textrm{M}$indole-3-butyric acid (IBA). Immature zygotic embryos were shown to be a suitable explant for embryogenic callus formation in the presence of 2, 4-dichlorophenoxyacetic acid(2, 4-D) in basal medium. Mature zygotic embryo originated leaves were used to test their ability for mophogenesis by incorporating plant growth regulators such as IBA, naphthyl-1-acetic acid (NAA), and 6-benzylaminopurine (BAP). Apparently, the morphogenetic responses of the cultured explant sources on the types and/or levels of plant growth regulators tested were observed visually.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.91-100
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• 2023

The early life history of Silurus microdorsalis living in Jahocheon Stream was studied by observing egg and morphological development. Live fish were captured in June 2018, then reared in a circulating filtration system under a 14L : 10D photoperiod with a water temperature of 18℃. To artificially induce spawning, females were injected with 0.5 mL of Ovaprim (Syndel, Nanaimo, BC, Canada) per kg of body weight, and males were injected with 10,000 IU/kg body weight of human chorionic gonadotropin. Approximately 15 h later, eggs were artificially inseminated by the dry method. Mature eggs were light pale yellow, which separated them from immature eggs. Fertilized eggs were 2.16±0.06 mm (n=8) in diameter and fully hatched at 181 h after fertilization. The fertilization rate was 63.1±2.2%, and 10.0±3.7% of the embryos were malformed at 18℃. The rates of development were 181 h at 18℃, 109 h at 21℃, and 76 h at 24℃. The larval size immediately after hatching was 4.64±0.22 mm (n=8), and the larvae displayed negative phototaxis at 1 day after hatching. The total larval length on 7 days after hatching was 12.47±0.53 mm, with 25~30 basal anal fin rays and 14~16 basal caudal fin rays observed. The total larval length was 14.13±0.51 mm on 9 days after hatching, and approximately 90% of the black endoplasmic reticulum was deposited on the head and body. The dorsal fin had formed, and a single basal body was observed. On 15 days after hatching, the total larval length was 16.69±0.31 mm; the number of basal caudal fin rays (18 poles) was an integer because 2 dorsal fin basal rays and 60~63 anal fin basal rays were observed. The total larval length was 28.96±1.10 mm on 50 days after hatching; the numbers of caudal fins (n=18), dorsal fins (n=3), pectoral fins (n=11), and anal fin basal rays (n=67~73) were integers.