• Fisheries and Aquatic Sciences
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• v.3 no.1
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• pp.23-25
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• 2000

To compare the respiratory burst activity potential of the phagocytes isolated from head kidney, spleen, and peripheral blood 1ll cultured rockfish (Sebastes schlegeli), chemiluminescent (CL) response analysis was performed. The phagocytes isolated from peripheral blood showed greater and faster CL response to the opsonized zymosan compared to that of the phagocytes isolated from kidney or spleen. This may imply a significant role of the blood phagocytes in defence mechanism of rockfish. The different responses found in the CL analysis among the phagocytes isolated from peripheral blood, kidney, and spleen may reflect differences in activation state or activity of phagocytes.

• Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.308-310
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• 2002

Effect of 4-nonylphenol (4-NP), endocrine disrupting compounds (EDCs), on glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) were investigated in the plasma of juvenile rockfish, Sebastes schlegeli. Fish were injected with 4­NP (10, 50, 100 and 200 mg/kg body weight) in $70\%$ ethanol twice at 3-day intervals and plasma sampling were extracted at 7 days after the last injection. Controls received solvent only. 4-NP significant increased GOT in a dose-dependent manner. GPT was markedly elevated to $61\%$ (P<0.05) and $82\%$ (P<0.01) than that of the control at the 4-NP doses of 100 and 200mg, respectively. These results suggest that the estrogenic activity of 4-NP increase plasma GOT and GPT by toxic effect on hepatocyte.

• Fisheries and Aquatic Sciences
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• v.6 no.4
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• pp.187-193
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• 2003

The performance of a foam fractionator to remove TAN, $NO_2,\;NO_3$, TSS, protein, and $PO_4-P$ at different superficial air velocities and foam overflow heights was evaluated in a lab-scale seawater recirculating system for culture of Korean rockfish (Sebastes schlegeli). The foam overflow rates increased with the increase of superficial air velocities, but decreased with the increase of foam overflow heights. Concentrations of all the water quality variables in the foam condensates increased with the increase of foam overflow height, but decreased with the increase of superficial air velocities. TSS, protein, and phosphate enrichment factors were within the range of 6.4-39.4, 1.6-7.3 and 1.2-3.9, respectively. Low values of TAN, $NO_2,\;and\;NO_3$ enrichment factors were obtained and they indicate that foam fractionation is rot an effective way to remove dissolved inorganic nitrogen. The calculated maximum daily removal values for TSS and protein were 10.9 and 1.4g, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.769-773
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• 2001

In order to obtain the fundamental data on the underwater sound of fishes for marine ranching. The underwater sound of Red Seabream(Pagrus major) and Schlegel's black rockfish(Sebastes schlegeli) were measured, which character were summarized by FFT analysis.

• Journal of Life Science
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• v.10 no.6
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• pp.548-557
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• 2000

A eight weeks feeding experiment was conducted to investigate the effects of different dietary dimethyl-$\beta$-propiothetin (DMPT) levels on growth and chemical components in Korean rockfish (Sebastes schlegeli). The content of DMPT extracted from Enteromorpha intestinalis by autoclaving was 31.1 mg%. Body weight gain and feed efficiency were significantly increased with dietary DMPT level. After eight weeks of feeding trial, moisture content decreased with supplemented DMPT level, while crude protein and lipid contents increased with dietary DMPT level. Amino acid contents of muscle was elevated in the DMPT added groups compared to control group. Amino acid composition of muscle in fish fed the diets supplemented DMPT was not different to that of control group. Fatty acid contents of muscle in fish increased with dietary DMPT level.

• Journal of fish pathology
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• v.16 no.2
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• pp.131-134
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• 2003

The change of membrane fluidity in rockfish (Sebastes schlegeli) phagocytes during respiratory burst was investigated. Fluorescence polarization (FP) was used as a measure of membrane fluidity, and 1-(4-trimethylaminophenyl)-6-phenyl-1 .3 ,5-hexatriene (TMA.-DPH) was used us a fluorescent probe. The significantly higher FP values in phagocytes stimulated With zymosan or phurbol myristate acetate (PMA) than unstimulated control phagocytes suggests that membrane fluidity of phagocytcs is decreased during the respiratory burst. The faster decrease of FP value in PMA stimulated phagocytes than in zymosan sumulated phagocytes may be due to bypass of the receptor-mediated stages of functional modulation. which is needed in zymosan stimulated phagocytes.

• Journal of fish pathology
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• v.11 no.1
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• pp.83-86
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• 1998

The benedeniine monogenean Benedenia derzhabini (Layman, 1930) Meserve, 1938 from cultured Korean rockfish, Sebastes schlegeli, is described and reported for the first time in Korea. The parasite was recovered from the gills and inner wall of operculum. B. derzhavini is distinguished from B. seriolae and B. sebastodis by the relative shape and length between the accessory sclerites and the hamuli.

• Fisheries and Aquatic Sciences
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• v.10 no.2
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• pp.60-67
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• 2007

Myostatin (MSTN; also known as GDF8) is a member of the transforming growth factor ${\beta}-superfamily$ of proteins. MSTN negatively regulates mammalian skeletal muscle growth and development by inhibiting myoblast proliferation. Mice and cattle possessing mutant MSTN alleles display a 'double muscling' phenotype characterized by extreme skeletal muscle hypertrophy and/or hyperplasia. We isolated the full-length cDNA of a novel MSTN gene from S. schlegeli muscle tissue and examined its expression pattern in various tissues. The full-length gene (GenBank DQ423474) consists of 1941bp with an open reading frame of 1134 bp, encoding 377 amino acids that show 62-92% amino acid similarity to other vertebrate MSTNs. The predicted protein contains a conserved proteolytic cleavage site (RXRR) and nine conserved cysteine residues at the C terminus. RT-PCR revealed that the unprocessed and prodomain myostatin mRNAs were predominantly present in muscle, with limited expression in other tissues. However, the mature myostatin mRNA was highly expressed in brain and muscle, intermediately expressed in the gills, intestine, heart, and kidney, and weakly expressed in the liver and spleen.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.5
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• pp.458-462
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• 2003

This study was to survey proper condition of nitrate removal by hydraulic retention time (HRT) and measured growth of black rockfish (Sebastes schlegeli) and giant croaker (Nibea japonica) in the seawater recirculating culture system designed for nitrate removal. Nitrate conversion to nitrogen at 8 hr-HRT was higher than 16 hr-HRT, amounting to $32.2\;g/m^3/day$ in the seawater recirculating culture system. The removal efficiency of nitrate improved when dissolved oxygen was situated less than 0.5 mg/L. Daily growth rate (DGR) and feed efficiency (FE) of S. schlegeli with mean body weight of 108 g in 8 hr-HRT were significantly higher values than those in 4 hr-HRT (P<0.05). The DGR and FE of N. japonica with mean body weight of 12 g in added carbon system showed not differing in the values from N. japonica in control system (P>0.05).

• Fisheries and Aquatic Sciences
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• v.19 no.2
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• pp.9.1-9.7
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• 2016

This study was conducted to identify the general conditions for the isolation and in vitro culture of ovary-derived cells in rockfish (Sebastes schlegeli). The effects of three different enzymes on cell retrieval from ovarian tissues were evaluated first, and then the ovary-dissociated cells were cultured under various culture conditions, with varying basal media and culture temperatures, addition of growth factors, and/or culture types. We found that collagenase type I treatment was effective for cell isolation from ovarian tissues. From a total of 42 trials to evaluate the effects of basal media and culture temperatures on cell culture of ovary-dissociated cells, we observed that Leibovitz's L15 medium was more supportive than Dulbecco's modified Eagle's medium for culture, and the cells could grow at all three temperatures tested, 15, 20, and $25^{\circ}C$, at least up to passage 2. However, growth factor addition did not improve cell growth. Introduction of suspension culture after monolayer culture expanded the culture period significantly more than did monolayer culture alone. Our results may provide a basis for developing an in vitro system for S. schlegeli germline cell culture, which will ultimately lead to improvement of the species.