• 생명과학회지
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• 제20권11호
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• pp.1634-1639
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• 2010

본 연구는 무지개송어 양식 산업의 생산성 향상을 위해 전 암컷 무지개송어 대량생산을 위한 일환으로 성호르몬에 의한 생리학적 성전환과 자성발생 2배체어를 유도하였다. 생리학적으로 성전환된 수컷을 만들기 위하여 부화 후 첫 먹이를 먹는 시기에 웅성호르몬인 17 alpha-methyltestosterone (MT) 5 mg을 사료에 흡착시켜 사육수온 $13^{\circ}C$에서 적산수온 $800^{\circ}C$까지 처리한 결과 96.7%의 수컷 유도율을 보였다. 또한 정상 수컷 정액을 이용하여 수정 10분 후 $28^{\circ}C$에서 20분간 고온 처리하여 61.7%의 자성발생 2배체가 유도되었다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.57-61
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• 2004

According to the research result of existing regarding the seabed organic sediment, contamination it flows from the land and the sea become the enemy in the coastal water. It was caused with the summer season water temperature rise and dispersing recall respect advancement. Phosphorus which is a main reason of red tide actual condition came to reveal vast quantity with the facts that it gushes. Specially, in the case of the coastal closing waters and the nursery, as the corpse and the fresh fish washing veterinarian was imbrued, it is the actual condition where is more deepened. Consequently the development of shallow layer dredging method of that suction power which is stabilized is demanded to be able to dredge only the sediment layer which has not become the pressure and is a main reason of being imbrued. The dredging methods using the pressure difference minimize the suction of the seabed sediment. This method is stable that suction power which occurs from guard difference of the guard and the guard of the dredging system inland water. That's why it is possible to sort dredging of the organic sediment ranging in upper layer sediment and it will be able to expect the minimization of dredging quantity. Increase of the expense that it followsin orthocenter with the fact will not grow. Because the pressure difference of the dredger inland water is occurred by the suction power. Maintenance administrative costs are reduced, because the one of smallest dredging system maneuvers and the barge which affixes an integrated operation system is mainly in a resting. To reduce a dredging hour, it will be able to solve in the condensed water as operating the jar guard post.

• 대한조선학회논문집
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• 제43권1호
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• pp.119-127
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• 2006

Recently as a result of excessive development. pollution of the coast and occurrence of a typhoon year after year, fishermen suffer heavy losses in fish farming which is the one of the most important earnings ways. For solution of these problems, we need to go out into the open sea from an inland sea. In this study we suggested new fish cage which makes up for the structural weakness of existing wooden fish cages. It can farm fishes in the open sea of high wave and current with no damages from a typhoon. We substituted TPU(Thermoplastic Polyurethane) air chamber for existing styrofoam flotage which was harmful to the environment and impermanent. We used PE(Polyethylene) pipes for the maintenance of formation and the prevention of buoyancy loss caused by a breakdown of flotage. PE b rackets were designed to combine PE pipes with TPU air-chamber flotage. It has good strength and light weight. As a result of modeling test. it is great in buoyancy, strength and flexibility against wave. Because it can control buoyancy arbitrarily, moreover, we expect that it will reduce damages of a red water by applying it as semi-submerged fish cages.

• 한국수산과학회지
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• 제42권3호
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• pp.262-267
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• 2009

Two 15-week feeding trials were conducted to investigate feeding rate and feeding frequency for growth of sub-adult flounder in suboptimal water temperature ($12^{\circ}C$). In the first experiment, duplicated groups of fish (initial mean weight of 279 g) were fed a extruded pellet once a day at the different feeding rates of 0.1, 0.15, 0.2, 0.3% body weight per day (BW/d), and satiation (0.32% BW/d). Weight gain and feed efficiency were increased significantly (P<0.05) with increase in feeding rates from 0.1 to 0.3% BW/d, but there were no significant differences in weight gain and feed efficiency of fish fed the diet between 0.3% BW/d and to satiation. Crude protein content of dorsal muscle of fish fed the 0.1% BW/d diet was significantly (P<0.05) lower than that of the other groups. In the second experiment, duplicated groups of fish (initial mean weight of 281 g) were fed to apparent satiation with a extruded pellet at three different feeding frequencies (one meal every two days, one meal a day and two meals a day). Weight gain, feed efficiency and condition factor of fish fed one meal every two days were significantly (P<0.05) lower than those of fish fed one meal and two meals a day, but there were no significant differences in weight gain, feed efficiency and condition factor of fish fed between one meal and two meals a day. Based on the results of this study, optimum feeding frequency is one meal a day with satiation feeding for growth and feed efficiency of sub-adult flounder (270-350 g) in suboptimal water temperature ($12^{\circ}C$).

• 한국수산과학회지
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• 제44권2호
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• pp.149-154
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• 2011

Two experiments were conducted to investigate the effects of dietary moisture content on the growth and gastrointestinal evacuation of sub-adult olive flounder (Paralichthys olivaceus) in the summer and winter seasons. In the first experiment, three experimental diets containing different moisture levels (7%, 15%) and additives were prepared by adding water and commercial additives (1% nutrients, 1% digestives) to commercial extruded pellets. Fish (initial weight: $332{\pm}9.2$ g) were distributed randomly into six 3000 L tanks (25 fish/tank) in a flow-through tank system. Two replicate groups of fish were fed the experimental diets to satiation for 14 weeks during the summer season ($21.4{\pm}2.5^{\circ}C$). Survival, weight gain, feed efficiency, and daily feed intake did not differ significantly among groups. In the second experiment, two experimental diets containing different moisture levels (8%, 23%) were prepared by adding water to commercial extruded pellets. Fish (initial weight: $646{\pm}6.7$ g) were randomly distributed into six 3000 L tanks (20 fish/tank) in a flow-through tank system. Three replicate groups of fish were fed the experimental diets to satiation for 19 weeks during the winter season ($12.2{\pm}1.2^{\circ}C$). Weight gain, feed efficiency, and daily feed intake did not differ significantly among groups. Gastrointestinal evacuation rates were determined after the end of the winter feeding trials. The stomach contents of fish fed diets containing different moisture levels peaked within 3 h after feeding and then decreased gradually over 40 h to approach pre-feeding levels. Intestinal contents began to accumulate 3 h after feeding and reached a maximum at 32 h, then declined until nearly complete evacuation around 56 h. The stomach contents reached moisture levels of approximately 70% within 3 h after feeding and then increased gradually. No considerable difference in moisture levels was observed in the stomach contents of fish fed diets with different moisture contents. The results of this study suggest that the gastric evacuation of sub-adult olive flounder was not affected by dietary moisture level and the addition of water to the diet had no beneficial effect on the growth of sub-adult olive flounder in the summer and winter seasons.

• 한국어병학회지
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• 제23권1호
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• pp.107-112
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• 2010

2007년 봄철 전남 여수 연안에서 자연 서식하는 복섬에서 Pseudocaligus sp.의 기생이 확인되었다. 숙주에 감염된 충은 preadult 및 adult 단계의 형태를 보였으며, 충체는 투명하였고 편평하며, 두흉부, 생식절, 복부로 구성되어 있었다. 충의 전단부에는 lunule이라고 하는 1쌍의 흡착구조물이 관찰되었다. 구제방법을 검토하기 위해 포르말린과 담수로 처리한 결과, preadult 및 adult 단계의 Pseudocaligus sp.는 50~400ppm의 포르말린 약욕처리에서 1시간 이내에 100%가 탈락 되었으나, 담수욕 처리에서는 90분 동안 57%의 탈락률을 보였다.

• 수산해양기술연구
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• 제59권4호
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• pp.387-398
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• 2023

Conventional aquaculture faces declining productivity, shifting to recirculating aquaculture system (RAS), known for minimizing water usage and maintaining consistent water temperatures for year-round fish growth. Rainbow trout (Oncorhynchus mykiss), a globally important cold-water species and the third most farmed fish in inland waters of Korea, valued for its fecundity and rapid growth. Dissolved oxygen, an important environmental factor affecting fish production and economics, highlights the need for smart aquaculture practices. Since 2018, the rise of intelligent aquaculture platforms, incorporating information and communications technology (ICT), emphasizes the essential role of RAS implementation. This eight-week study aimed to determine the optimal dissolved oxygen concentration for rainbow trout in RAS, utilizing a device for continuous monitoring, control and record. Dissolved oxygen concentrations were set at 5-6 mg/L, 9-10 mg/L, 14-15 mg/L and 17-18 mg/L. The growth rate significantly decreased at 5-6 mg/L, with no significant differences in other experimental groups. In hematological analysis, growth hormone (GH) was significantly highest at 5-6 mg/L, followed by 9-10 mg/L while Insulin-like growth factor-1 (IGF-1) was significantly lowest at 5-6 mg/L. In conclusion, the optimal dissolved oxygen concentration for rainbow trout in RAS is approximately 9-10 mg/L. Higher concentrations do not contribute to further growth or profitability.

• 한국어류학회지
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• 제30권2호
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• pp.84-91
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• 2018

본 논문은 소양호에 서식하는 내수면어업의 주요 수산자원 중 하나인 쏘가리(Siniperca scherzeri)의 성숙과 산란에 관하여 연구하였다. 본 논문에 사용된 쏘가리는 2014년 4월부터 11월까지 정치망과 자망을 통해 채집하였고, 암컷이 204개체로 전장범위는 113~365 mm이었고, 수컷은 197개체로 전장 범위가 140~342 mm이었다. 산란기가 시작되는 5월의 수온은 $15^{\circ}C$를 나타냈으며, 점진적으로 높아져 7월에 $26^{\circ}C$를 나타내었다. 암컷의 생식소 숙도지수(GSI)는 5월에서 7월까지 각각 2.3%, 4.6%, 3.1%로 나타났고, 수컷의 경우 8.0%, 6.6%, 4.5%로 나타났다. 난소 조직은 5월에 많은 수의 샘플이 중숙으로 관찰되었으며 6월에는 대다수가 성숙, 7월에는 완숙 및 방란으로 관찰되었다. 정소 조직의 경우에도 마찬가지로 5월에는 대다수가 중숙, 6월에는 성숙, 7월에는 방중으로 관찰되었다. 월별 성숙도와 생식소 숙도지수 (GSI), 생식소의 조직관찰을 통한 분석결과, 소양호에 서식하는 쏘가리의 산란기는 5월에서 6월로 추정되었다. 또한 군성숙도를 분석한 결과, 암컷 쏘가리의 50% 성숙체장은 245.16 mm로 나타났다.

• 한국어류학회지
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• 제25권4호
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• pp.200-207
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• 2013

우리나라 고유종인 참갈겨니를 2011년 남한강에서 채집하여 Zacco속의 유연관계와 종 보존의 기초자료를 얻기 위하여 난 발생 과정과 초기생활사를 연구하였다. Z. koreanus 난은 실험실에서 건식법으로 수정되었다. 수정란은 원형이고 투명하며, 엷은 황색난황을 가지고 있고, 유구가 없으며, 약한 점착성 침성란으로 난경은 $3.09{\pm}0.07$ mm(n=10)이었다. 수온 $20.0{\sim}23.0^{\circ}C$에서 수정 후 68시간 전후하여 난 발생이 완성되었으며, 부화자어의 크기는 전장 $10.30{\pm}0.40$ mm (n=10)이었다. 부화 6일 후에는 전장 $16.12{\pm}0.42$ mm(n=8)로 성장하였고, 난황이 거의 흡수되었으며 입과 항문이 열린 후기자어기가 되었다. 부화 17일 후에는 전장 $18.21{\pm}0.38$ mm(n=6)로 자랐고, 대부분의 지느러미에 기조가 나타났으며, 복부에는 갈색반점이 출현하였다. 부화 27일 후에는 전장 $20.01{\pm}1.12$ mm(n=5)로 성장하였고, 모든 지느러미의 기조수가 정수에 도달하였다. 부화 120일 후에는 전장 $23.29{\pm}3.12$ mm(n=10)로 성장하였으며, 외형과 반문이 성어와 유사하였다.

• 한국어류학회지
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• 제10권1호
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• pp.1-10
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• 1998

쏘가리 Siniperca scherzeri의 양식과 자원증강을 위한 기초자료를 얻기 위하여 초기생활사에 대한 연구를 실시하였다. 친어는 1996년 6월부터 1997년 7월까지 소양호 중류(강원도 춘천시 북산면 물노리)에서 채집하였다. 성숙된 암컷에 HCG나 GnRH - a 호르몬을 복강 주사하여 배란을 유도하였고, 건도법으로 수정하였다. 수정란은 분리되었으며, 약한 침성란이었고, 0.50~0.70mm의 커다란 유구가 난황 중앙에 한개 있었다. 수정 직후 난의 크기는 1.70~2.10mm였으나, 배반이 형성될때는 물을 흡수하여 2.20~2.66mm로 커졌다. 수정 1시간 후에 배반을 형성하기 시작하였고, 1시간 30분 후에는 난할이 시작되었다. 이 후 난내 발생은 수온 $21{\sim}24^{\circ}C$에서 약 50분 간격으로 계속 진행되었다. 수정 131시간 30분 후에는 부화되었는데, 부화자어의 크기는 전장 5.86~6.85mm였고, 난황의 표면과 꼬리 부분의 복부에는 많은 흑색소포가 발달되었다. 부화 3일 후에는 전장 6.98~7.60mm로 자랐고, 단황은 대부분 흡수되었으며, 이빨이 발달되었다. 부화 15일 후에는 전장 10.10~12.90mm였으며, 머리에 가시와 이빨이 매우 발달되었고, 모든 지느러미가 정수에 도달하는 후기자어기(postlarvae stage)가 되었다. 부화 25일 후에는 전장15.30~23.80mm로 성장하였고, 체형과 반문이 성체와 유사해졌다. 부화 5개월 이후에는 전장 154.00~175.02mm, 체중 49.32~82.67g까지 성장하였다.