• 한국발생생물학회지:발생과생식
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• 제19권4호
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• pp.253-258
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• 2015

Spermiation was stimulated in the mature grass puffer, Takifugu niphobles, with an injection of human chorionic gonadotropin (HCG) or carp pituitary extract (CPE). Spermatocrit and sperm density were reduced, but milt production was increased in both the HCG and CPE treatment groups relative to those in the control group (P < 0.05). These results should be useful for increasing the fertilization efficiency in grass puffer breeding programs.

• 수산해양기술연구
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• 제58권3호
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• pp.205-213
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• 2022

The experimental fish transplanted from China in 2015 was used after seedling production and cultivated. Breeding management for experiment was carried out from October 2020 to February 2021. Also, it succeeded in inducing artificial maturation three to four months earlier than wild broodstock and secured good quality fertilized eggs. The average size of fertilized eggs was 1.22 mm, at 20℃ Blastodisc (15 minutes post-fertilization), 2 cell (50 minutes), 4 cell (1 hours), 8 cell (2 hours), 16 cell (2 hours and 30 minutes), 32 cell (2 hours and 50 minutes), morula (3 hours), blastula (8 hours), gastrula (15 hours), skull formation (20 hours), organ formation (30 hours) and hatching yolk larvae stage (35 hours). The total length of the just hatched larvae were 2.50 ± 2 mm, and then gain growth of 42.5 mm by 60 days, reaching 45 ± 5 mm.

• Ocean Science Journal
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• 제40권3호
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• pp.177-182
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• 2005

The process of embryogenesis and larval development of the asteroid sea star Asterias amurensis $(U{\ddot{u}}tken)$ was observed, with special attention paid to morphological change and larval duration. In reproductive season, mature sea stars were collected under floating net cages, located in Tongyeong, southern Korea. The mature eggs are $138\;{\mu}m$ in average diameter, semi-translucent and orange in color, sperms in good condition appear light cream to white-gray in color. Embryos develop through the holoblastic equal cleavage stage and a wrinkled blastula stage that lasts about 9 hours after fertilization. Gastrulae bearing an expanded archenteron hatch from the fertilization envelope 22 hours after fertilization. At the end of gastrulation, rudiments of the left and right coelom are formed. By day 2, larvae possess complete alimentary canal and begin to feed. At this stage, the larva is called early bipinnaria. In 6-day-old larvae, the pre- and post- oral ciliated bands form complete circuits and the bipinnarial processes start to develop. By day 12, the lateral and anterior projection of the larval wall processes along the ciliated bands begins to thicken and curl, and the ciliated bands become more prominent. By day 32, early brachiolaria are presented with three pairs of brachiolar arms. Advanced brachiolaria with a well-developed brachiolar complex (three pairs of brachia and central adhesive disc) occur 6 weeks after fertilization. In the field, spawning of the sea star was observed in April to May, settlement form larvae and just settlements seem to occur from June to July, and early juveniles occur from August to September. Although we had not described the end of brachiolaria stage, it can be tentatively estimated that the duration of the pelagic stage of A. amurensis is 40 to 50 days.

• 한국산학기술학회논문지
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• 제17권4호
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• pp.692-697
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• 2016

해수산 rotifer Brachionus rotundiformis의 내구란 대량생산을 위한 효과적인 유성생식자극요인을 구명하기 위해 염분자극과 기사용배양수의 효과를 9일 동안 조사하였다. 각 염분에 노출된 후 모든 실험구에서 배양 3일째부터 유성생식률이 증가하기 시작했으며 이후 배양 4-5일째 이후 감소하는 경향을 보였다. 내구란은 10‰, 15‰, 20‰, 25‰ 실험구에서 배양 4일째에 출현하였으며 특히 20, 25‰ 실험구는 배양 6일째 수정률이 각각 33.3%와 31.3%로 다른 실험구에 비해 높게 나타났다. 9일간 평균 유성생식률은 10‰와 20‰ 실험구에서 각각 25.3%와 20.2%로 높게 나타났다. 수정률은 25‰ 실험구에서 14.0%로 가장 높았다. 각 기사용배지농도에 노출된 후 모든 실험구의 유성생식률은 염분실험결과와 유사한 경향을 보였고 내구란은 0%과 25% 기사용배지에 노출되었을 때 만 출현하였다. 평균수정률은 모든 실험구가 차이를 보이지 않은 반면, 유성생식률은 25% 실험구가 22.3%로 대조구인 0%에 비해 높게 나타났다. 본 연구결과를 종합해보면, B. rotundiformis의 내구란 대량생산을 위한 효과적인 유성생식유발요인으로 기배양수자극보다 염분자극이 더 효과적이며 최적 염분은 비교적 높은 유성생식률과 수정률을 유도한 20-25‰로 판단된다. 본 연구결과는 차후 rotifer 내구란 대량생산을 위한 핵심적인 기초자료로 활용될 수 있을 것으로 판단된다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2009년도 춘계학술발표회
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• pp.163-163
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• 2009

• 수산해양교육연구
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• 제29권2호
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• pp.409-414
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• 2017

Effects of human chorionic gonadotropin (HCG) on ovulation and spawning of the grass puffer, Takifugu niphobles, were investigated. Matured females spawned successfully by all doses of HCG. Spawning usually occurred 24 hours after hormone injection. Body weight of adult, gonadsomatic index (GSI), pseudo-GSI, body weight of spawned egg, success rate of spawn, fertilization rate, hatching rate, and survival rate of juvenile were correlated with increasing HCG doses. However, abnormal rate of juvenile was not correlated with increasing HCG doses. These results should be useful for developing aquaculture program of grass puffer.

• 환경생물
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• 제38권2호
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• pp.323-331
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• 2020

해산송사리(Oryzias dancena)를 대상으로 한 발생공학 연구시, 현재의 자연산란법은 매우 수동적이고 불편하다. 본 연구에서는 적정 시간에 해산송사리의 수정란을 획득하고자 인공산란을 위한 인간융모성생식선자극 호르몬(human chorionic gonadotropin; HCG)과 잉어 뇌하수체(carp pituitary extract; CPE)의 최적 농도를 조사하였다. 정자활성도, 산란율, 수정 후 3일에서의 수정란 생존율 및 부화율은 100 HCG IU kg^-1 BW (body weight)와 CPE 5 mg L^-1에서 가장 높았다(p<0.05). 본 종에서의 수정란 필요시, HCG와 잉어 뇌하수체 주사를 통하여 적정시간에 미수정란과 정자를 획득할 수 있었다. 본 연구 결과는 해산송사리의 실험동물화 개발에 유용하리라 사료된다.

• 한국패류학회지
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• 제19권2호
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• pp.107-110
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• 2003

The effect of broodstock age on the spawning performance of cultured abalone, Haliotis discus hannai, was assessed for five age groups (3, 4, 5, 6, 7 years old). Spawning performance of the five age groups was assessed in terms of the percentage of spawning abalone, eggs per spawning female, fertilization rates, hatch rates and attachment rates per spawning. The percentage of spawning abalone increased along with broodstock age, reached maximum in female groups of 5- and 6-year age (60%), and in male group of 6-year age (100%), subsequently decreased in 7-year age group. The number of eggs produced per spawning also increased with broodstock age, and the maximum was found in 6-year age. Although the number of spawned eggs for the oldest abalone declined, it still spawned much more eggs than 3, 4, and 5 years old females. The fertilization and hatch rates were obviously larger for 4-6 years old group than the younger and older abalones. The maxima were found in 5-year age group (96.0% and 84.5%), and the minimum were appeared in 7-year age group (79.3% and 58.2%). The attachment rate increased with broodstock age, reached maximum in 6-year age group (33.6%), although the increment gradually declined. The attachment rate for 7-year age group rapidly decreased (16.6%). These results suggested that broodstock age affected the spawning performance of H. discus hannai, which peaked between 5 and 6 years old, and broodstock should be bred during this period for hatchery production.

• 한국발생생물학회지:발생과생식
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• 제20권4호
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• pp.305-314
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• 2016

The marine medaka, Oryzias dancena is a suitable sample as a laboratory animal because it has a small size and clearly distinguishes between female and male. Data on the growth and maturity of the diploid and triploid sea cucurbit species suitable for laboratory animals are very useful for studying other species. Triploidy was induced in the marine medaka by cold shock treatment ($0^{\circ}C$) of fertilized eggs for 45 min, applied two minutes after fertilization. The diploid and triploid male fish were larger than their female counterparts (P<0.05), and the concentrations of thyroid stimulating hormone (TSH) and thyroxine (T4) were higher in the induced triploids over 1 year (P<0.05). In both the diploid and tri-ploid groups the concentrations of TSH and T4 were higher in the male fish than in the females (P<0.05), while the testo-sterone and estradiol-$17{\beta}$ concentrations in the induced triploids were lower than in the diploids (P<0.05). The gonadosomatic index (GSI) of the triploid fish was lower than that for the diploids, and the GSI for females in each ploidy group were higher than that for the males. For both groups the GSI was highest at 4 months of age, and decreased thereafter to 12 months. Analysis of the gonads of one-year-old triploid fish suggested that the induction of triploidy probably causes sterility in this species; this effect was more apparent in females than in males.

• 한국산학기술학회논문지
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• 제13권8호
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• pp.3785-3791
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• 2012

용존산소란 수생생물의 생장을 조절하는 가장 중요한 요소 중의 하나이다. 일반적으로 빈산소란 2.8 mg $O_2/L$ (91.4 mM과 동량) 이하의 용존산소로 정의된다. 따라서 빈산소 해역은 해양생태계에서 심각한 문제를 야기할 수 있다. 본 연구에서는 성게에 대한 빈산소의 배아독성 (수정 및 배발생률) 영향을 연구하기 위하여 둥근성게 (Strongylocentrotus nudus)를 용존산소 7.6 mg $O_2/L$ (normoxia)과 1.8 mg $O_2/L$ (hypoxia)에서 2일, $15^{\circ}C$ 및 33 ‰에 노출하였다. 또한 빈산소에 노출된 성게에서의 스트레스 관련유전자인 HSP70과 항산화 관련 유전자인 glutathione reductase의 발현을 immunoblotting assay와 RT-PCR을 통하여 확인하였다. 연구결과 배발생률이 현저하게 감소하였다. 분자분석 결과 빈산소에 노출된 성게가 정상상태의 성게에 비해 HSP70 단백질은 약 5.5배 glutathione reductase는 약 2.79배 증가하였다. 본 연구의 결과는 빈산소가 성게의 비정상적 배발생을 유도하며, 스트레스와 항산화 반응을 유발할 수 있음을 추측케 한다.