• 한국어병학회지
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• 제14권2호
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• pp.91-95
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• 2001

1999년 10월에서 11월 사이에 남해안 일대의 홍민어 종묘 생산장에서 20~30열령의 치어가 척추만곡 및 이상유영을 하며 대량 폐사하였다. 병어는 특이 외부 증상이 없었고, 높은 누적폐사량이 바이러스 질병으로 의심되어, 조직학적 및 분자생물학적인 검사를 행하여 폐사원인을 확인하였다. 폐사개체의 조직을 H-E 염색하여 관찰한 결과 뇌와 안구의 신경세포에서 공포와 괴사가 관찰되었고, 전자현미경 관찰에서는 안구와 뇌에서 바이러스 입자가 관찰되었다. RT-PCR 결과에서는 ${\fallingdotseq}426$ bp의 DNA 단편을 확인할 수 있었다. 이러한 결과로 홍민어에서 발생한 대량폐사는 바이러스성 신경괴사증(VNN)으로 진단되었다.

• 한국수산과학회지
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• 제43권6호
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• pp.654-658
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• 2010

The purpose of this study is to establish methods for enhancing the survival and growth of cold-water fish and crustacean larvae based on the nutritional components of zoo and phyto live foods. Rotifers, Brachionus rotundiformis, were cultured with a supplement of freshwater condensed Chlorella vulgaris at $28^{\circ}C$ and enriched with Algamac $2000^{(R)}$ at 16, 20 and $26^{\circ}C$, respectively. Isochrysis galbana, Chaetoceros calcitrans and Chlorella ellipsoidea were centrifuged for component analysis after being cultured for approximately one week with conway medium at $20^{\circ}C$. The crude protein and lipid contents of the rotifers were 58.4% and 10.9%, respectively, before enrichment. After enrichment at each temperature, total protein and essential amino acid contents were increased by reducing the enrichment temperature. However, unsaturated fatty acids and multiple fatty acid index (UI) showed their highest values at $20^{\circ}C$. Mono-unsaturated fatty acid content was highest (72.6%) at $16^{\circ}C$. The total protein contents of C. calcitrans and C. ellipsoidea were higher, 33.0% and 35.2%, respectively, than that of I. galbana, 27.8%. Methionin, leusine and histidine, essential amino acids of C. ellipsoidea, had considerably higher values, 50.2, 287.2 and 68.1 mg/g dry matter, respectively, compared to other microalgae. Total lipids, UI, DHA and n-3 PUFA of I. galbana had higher values, 23.6, 272.0, 12.9% and 45.2%, respectively, than other microalgae. Therefore, for cold-water fish and crustacean larvae that require high n-3 PUFA and DHA contents, enrichment of rotifers is desirable at $20^{\circ}C$. Fish larvae would also need more I. galbana than other microalgae.

• 한국수산과학회지
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• 제27권5호
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• pp.620-632
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• 1994

아산만 주변 해역의 부유성 난과 자치어 분포를 조사하기 위하여, 1991년 4월, 7월, 10월 및 1992년 1월 4회에 걸쳐서 RN 80Net를 이용하여 부유성난과 자치어를 표층 채집하여 분류 동정하였다. 본 해역에서 출현한 부유성 난은 민어속 어류, 멸치, 동갈양태속어류 및 기타로 분류되었는데, 조사 기간중 민어속 어류의 난이 전체 어란 출현량의 $97.70\%$를 차지하여 우점종으로 나타났다. 자치어는 총 23개 분류군이 출현하였는데, 조사기간중 망둑어과 어류는 7종이 출현하여 전체 자치어 출현량의 $32.84\%$를 차지하여 극우점종으로 나타났으며, 까나리가 $16.69\%$를 차지하여 우점종으로 나타났다. 그 이외에도 뱀장어, 민어속어류, 덕대 및 멸치가 주요 출현종을 이루었다. 이들 6개 분류군은 자치어 출현량의 $90.40\%$를 차지하였다. 본 해역의 내만쪽에서는 담수의 영향으로 아산호에 인접한 정점에서는 자치어 분포에 큰 영향을 미치는 것으로 나타났으며, 외해쪽 보다는 이들 기수 지역에서 많은양이 출현하여 부유성 난과 차지어 분포에 영향을 미치는 것으로 나타났다.

• 한국수산과학회지
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• 제50권3호
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• pp.287-295
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• 2017

Egg development and morphological change of larvae of the Sakhalin sole Limanda sakhalinensis were studied by observing specimens obtained in a rearing experiment from fertilized eggs to the juvenile stage. The wild broodstock was collected in January 2010 and kept in a circular water tank (${\O}1.5{\times}1m$) at a temperature of $14.5{\pm}0.5^{\circ}C$. Fertilized eggs ranged from 0.72 to 0.82 mm ($0.77{\pm}0.07mm$, $mean{\pm}SD$) in diameter. The eggs were spherical, transparent and adhesive demersal. The egg yolk was divided from the oocyte 10 min after fertilization (AF), and an embryo was formed in 36 h AF. More than 50% of the eggs hatched within 133 h AF. The mouth and anus did not open until $3.5{\pm}0.25mm$ total length (TL). At 4, days after hatching (AH), the fish became larvae 3.7 to 4.2 mm ($4.0{\pm}0.36mm\;TL$), yolk absorption was completed and the mouth began to open. The left eye moved upward and the nostril moved to the right at 39 days AH. These post-larvae ranged from 8.0 to 9.9 mm TL ($8.9{\pm}1.33mm\;TL$). At 50 days AH, the fish became juveniles ($12.4{\pm}1.20mm\;TL$) There were 70-72 dorsal fin rays, 55-56 anal fin rays, 11 pectoral fin rays, and 6 ventral fin rays and the juveniles adopted a benthic life.

• 한국양식학회지
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• 제12권1호
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• pp.31-38
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• 1999

넙치(Paralichthy olivaceus) 및 돌돔 (Oplegnathusfasciatus) 자어를 대상으로 각각 B.plicatilis와 B.rotundiformis의 내구란에서 갓 부화한 rotifer의 먹이효율과 지방산 조성을 대량배양한 rotifer와 비교 조사하였다. Rotifer 내구란은 Chlorella와 빵 효모를 먹이로 공급하여 $1~4m^3$에서 생산하였다. B.plicatilis와 B.rotundiformis 내구란은 $5^{\circ}C$ 암내장 상태에서 각각 3개월과 5개월 동안 보관하여 $28^{\circ}C$ 연속 조명하에서 부화시켰다. 내구란에서 갓 부화한 rotifer와 대량 배양한 rotifer(대조구)를 자어에게 공급하였다. B.rotundiformis 내구란에서 갓 부화한 rotifer를 공급한 돌돔자어의 성장과 생존률은 대조구와 비슷하였게 나타났고, B.plicatilis 내구란에서 갓 부화한 rotifer를 먹은 넙치자어의성장과 생존률은 각각 대조구에 비해 비슷하거나 높게 나타났다. 또한 내구란에서 갓 부화한 rotifer의 지방산조성은 대조구와 비슷하게 나타났다. 이와 같은 결과를 볼 때 내구란에서 갓 부화한 rotifer는 넙치 및 돌돔 자어의 먹이로서 이용 가능하다고 판단된다.

• Fisheries and Aquatic Sciences
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• 제19권4호
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• pp.20.1-20.12
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• 2016

The osteological development in Sebastes koreanus is described and illustrated on the basis of 32 larvae [6.11-11.10 mm body length (BL)] and a single juvenile (18.60 mm BL) collected from the Yellow Sea. The first-ossified skeletal elements, which are related to feeding, swimming, and respiration, appear in larvae of 6.27 mm BL; these include the jaw bones, palatine, opercular, hyoid arch, and pectoral girdle. All skeletal elements are fully ossified in the juvenile observed in the study. Ossification of the neurocranium started in the frontal, pterotic, and parietal regions at 6.27 mm BL, and then in the parasphenoid and basioccipital regions at 8.17 mm BL. The vertebrae had started to ossify at ~7.17 mm BL, and their ossification was nearly complete at 11.10 mm BL. In the juvenile, although ossification of the pectoral girdle was fully complete, the fusion of the scapula and uppermost radial had not yet occurred. Thus, the scapula and uppermost radial fuse during or after the juvenile stage. The five hypurals in the caudal skeleton were also fused to form three hypural elements. The osteological results are discussed from a functional viewpoint and in terms of the comparative osteological development in related species.

• 한국수산과학회지
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• 제53권6호
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• pp.894-899
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• 2020

This study investigated the effects of inclusion of pollock oil (PO) in the diet of broodstock on the egg and larval quality of Walleye Pollock Gadus chalcogrammus. The experimental diet comprised of semi-moist pellets prepared either with or without PO (control; Con). The fish assigned to each diet were fed to visual satiation (two meals per day) for 12 weeks. Eggs spawned from both groups of fish were sampled during the spawning season (three months) and the egg and larval quality was determined. Total egg volume, fertilization, and hatchability of eggs from the PO group were higher than those of the Con group. Fatty acid composition of fertilized eggs was not affected by the experimental diet. Oleic acid, eicosapentaenoic acid, and docosahexaenoic acid content in larvae of the PO group was higher than that in larvae of the Con group. These results demonstrate the beneficial effects of including PO in the broodstock diet of Walleye Pollock, specifically on the quality of the eggs (total egg volume, fertilization, and hatchability) and larvae (fatty acid composition).

• 한국발생생물학회지:발생과생식
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• 제21권1호
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• pp.63-69
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• 2017

On the 15 days after hatching, the larvae was 4.24-5.10 mm (mean $4.66{\pm}2.18mm$) in total length, and the fins of the membrane started to develop into a fan shape and the melanophore was deposited upper the alimentary canal of the abdomen and on the bladder. At 35 days after hatching, the post-larvae formed a branch-shaped melanophore on the head part with a total length of 6.98-12.5 (mean $9.35{\pm}1.71$) mm, formed on the upper and lower parts of the caudal part, formed on the upper and lower parts of the caudal part, and deposited under the head part and abdomen. At 40 days after hatching, the juvenile was 11.3-18.1 (mean $14.9{\pm}1.53$) mm in total length.

• 한국수산과학회지
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• 제40권4호
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• pp.183-186
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• 2007

The effect of live food and commercial diet on sweetfish Plecoglossus altivelis culture was assessed by determining the daily growth rate and feed conversion ratio. After feeding for 8 weeks, the Moina macrocopa diet resulted in a higher growth rate of 5.101 compared to commercial (3.441) and Artemia (2.729) diets. In addition fish fed the M. macrocopa diet had the weight gain, averaging 41.29 g at the end of the experiment. The content of n-3 highly unsaturated fatty acids (HUFA) was highest in the commercial diet, while free fatty acids were not detected in the M. macrocopa diet. Triglycerides, the energy source in fishes, constituted 40.0% of the M. macrocopa diet, which was significantly higher than in the commercial and Artemia diets at 20.0 and 12.0%, respectively These results indicate that freshwater M. macrocopa can be used as feed for sweetfish larvae, even without docosahexaenoic acid (DHA) enrichment from Artemia.

• 한국어류학회지
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• 제23권1호
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• pp.37-45
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• 2011

진해만 남서부에 출현하는 자치어 종조성의 계절변동을 연구하기 위하여 2009년 1월에서 12월까지 매월 RN80 네트을 이용하여 시료를 채집하였다. 조사 기간 동안 24과 46종의 자치어가 채집되었다. 우점종은 청어(Clupea pallasii), 쥐노래미(Hexagrammos otakii), 전어(Konosirus punctatus), 멸치(Engraulis japonicus), 청베도라치(Parablennius yatabei), 앞동갈베도라치(Omobranchus elegans) 순으로 많이 채집되었는데 이들 6종은 전체 채집개체수의 92.7%를 차지하였다. 어종수, 채집 개체수, 종다양도지수는 뚜렷한 계절 변동을 나타내었다. 종수와 개체수는 각각 7월과 1월에 가장 높은 값을 나타내었다. 주성분분석(PCA)와 상관분석은 군집구조와 우점종들의 출현량이 수온과 유의한 관계가 있음을 보여주었다. 특히, 청어, 쥐노래미, 멸치, 청베도라치의 출현량은 수온과 유의한 관련성이 있었다.