• Journal of fish pathology
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• v.1 no.2
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• pp.73-76
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• 1988

There prevailed lymphocystis disease with 1 to 2cm in size in the skin and pins of cultured Sebastes schlegeli in fish farms in Tongyoung-gun, Sanyang-myeon, Kon-ri from summer, 1987 to fall, 1988. Though there were some difference between each fish farm, this disease prevailed widely from immature fish to mature fish, less than 10cm to 30cm in body length with about 8 through 80% of infection rate. Sebastes schlegeli with the lymphocystis disease showed combined nipple-shaped mass by doubly, triply propagated lymphocystis. But the author considered that lymphocystis disease was not a direct cause of death of Sebastes schlegeli, the fish showed marked inflammation by seconary infection of pathogenic organisms.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.5
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• pp.308-314
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• 2007

The feeding habits of Sebastes schlegeli collected from the Tongyeong marine ranching area throughout 2002 were studied. S. schlegeli is a carnivore (piscivore), and consumed mainly fish. Its diet also included a small amount of caridean shrimps, crabs, amphipods, polychaetes, and isopods. The diet of S. schlegeli underwent size-related changes. Small individuals (standard length (SL)<6 cm) fed mainly on fishes, caridean shrimps, and amphipods, and the proportion of fish increased with SL. Large individuals (SL>20 cm) ate fish predominately. The diet of S. schlegeli changes seasonally, and caridean shrimps were consumed mainly from May to July. The dietary breadth index of S. schlegeli varied with SL and season.

• Journal of Aquaculture
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• v.11 no.3
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• pp.345-352
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• 1998

The effect of starvation on the growth and hepatocyte nuclear size of larval rockfish Sebastes schlegeli and spotted sea bass Lateolabrax sp. were studied. The growth of total length and wet weight in both rockfish and spotted sea bass starved were lower than their control counter-parts. The nuclei sizes of parenchymal cells in the liver of rockfish and spotted sea bass were correlated with the nutritional status of their first-feeding larvae. The result suggested that hepatocyte nuclear size in rockfish and spotted sea bass could be used as an alternative indicator for the identification of starving condition and such karyometry might be criteria for evaluating the successful transition from endogenous to exogenous feeding regime.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.05a
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• pp.24-24
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• 2002

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.2
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• pp.146-153
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• 2016

A feeding experiment was conducted to determine the nutritional value of various dietary protein sources without a vitamin premix supplementation in juvenile black rockfish, Sebastes schlegeli. Diets containing similar quantities of lipid and carbohydrate with 50% crude protein from fish meal (FM)/soybean meal (SBM)/corn gluten meal (CGM), FM only, casein/gelatin, high FM/low casein and low FM/high casein were fed to rockfish along with a commercial rockfish diet. The diet containing only 65.6% FM and the commercial rockfish diet produced significantly greater weight gain (WG) and feed efficiency (FE) than all other semipurified diets (SPDs); the economical diet with 52.8% FM, 10% SBM and 5% CGM produced lower WG than the diet containing FM and commercial rockfish diet, but FE and survival were similar both diets. Intermediate responses were observed for rockfish fed the SPD containing 32.8% FM and 27.4% casein, while SPDs containing 10% FM and 41.8% casein and 38.5% casein and 10% gelatin yielded the lowest WG and FE. Some differences in tissue indices and body composition of rockfish were induced by the diets containing various protein sources and levels without the vitamin premix supplementation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.540-545
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• 2013

This study investigated the effect of diets supplemented with different levels (0, 1, 3, and 5 %) of turmeric Curcuma longa L. powder (TP) on the body composition of black rockfish Sebastes schlegeli. Fish weighing $10.05{\pm}0.44$ g were fed to apparent satiation twice daily for 8 weeks. Adding TP decreased crude lipid levels and increased crude protein and ash levels. Abundant fatty acids in the TP-added group were C16:0, C18:1 n-9 (cis), and C22:6 n-3. The major amino acids in samples were glutamic acid, aspartic acid, glycine, leucine, alanine, lysine, and arginine.

• Environmental Analysis Health and Toxicology
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• v.17 no.3
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• pp.239-243
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• 2002

Changes of plasma vitellogenin (VTG) and glutamate pyruvate transaminase (GPT) were examined for determining whether hepatocyte was damaged during the process of VTG induction in the juvenile rockfish, Sebastes schlegeli exposed to exogenous estrogen (estradiol-l7$\beta$, E$_2$). Rockfishes were intraperitoneally injected with E$_2$(5 mg/kg B.W.) in 70% ethanol and plasma sampling were extracted at 0, 1, 3, 6, 9, 12, 15 days af-ter E$_2$administration. VTG and GPT were then analyzed by SDS -PAGE and Reitman -Frankel method, respectively. VTG band was detected at a molecular weight position of 175 kDa on Day 3 after E$_2$administration. This band became more distinct at 6 days, but its was gradually thinned with time -course, and not detected at 15 days. GPT was suddenly increased at 1 days after 22 administration and highest GPT was detected at 3 days. However. GPT was gradually decreased with time -course as the change of VTG. These results suggest that the process of VTG induction by exogenous E$_2$damage to hepatocyte, and plasma GPT was temporarily increased in the juvenile rockfish.

• Journal of Life Science
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• v.18 no.6
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• pp.782-788
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• 2008

The aim of this work is to show differences in the pattern of glycoconjugate composition in the intestines of four teleostean species (Sebastes schlegeli, Halichoeres poecilopterus, Bryzoichthys lysimus, and Takifugu pardalis). We compared four regions of all species studied. The specimens were processed and stained with nine kinds of biotinylated lectins (DBA, SBA, PNA, BSL- I , RCA- I , sWGA, UEA- I , LCA and Con A). Except for Sebastes schlegeli, no differences between regions were observed. The intestinal epithelium of Halichoeres poecilopterus possessed D-glucose/mannose residues in all regions. ${\beta}$-N-acetyl-D-galactosamine was distinctive along the intestines, although the pattern of diversity was different in Sebastes schlegeli, Bryzoichthys lysimus, and Takifugu pardalis. Additionally, the occurrence of Galactose-${\beta}$-1,3-N-acetyl-D-galactosamine and ${\alpha}$-D-galactose were confirmed in the proximal, middle, and distal intestine of Sebastes schlegeli, while rectal intestine lacked these sugar residues. Along with ${\beta}$-N-acetyl-D-galactosamine, ${\beta}$-N-acetyl-D-glucosamine and D-glucose/mannose were also determined in Bryzoichthys lysimus. Galactose-${\beta}$-1,3-N-acetyl-D-galactosamine, D-galactose, and D-glucose/mannose were also present in Takifugu pardalis.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.387-393
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• 2004

Experiments were carried out to investigate the lipid peroxidation (LPO), superoxide dismutase (SOD) activity and histopathological change of hepatic tissue for rockfish, Sebastes schlegeli after feeding sub-chronic dietary Benzo(a)pyrene (BaP) in the concentration of 0 (control), 0.5, 1.0, 1.5, 2.0 mg $kg^{-1}$ dry food of diet for 30 days. In 2.0 mg $kg^{-1}$ dry food group, the significant increase of LPO was observed in all period, and SOD activity was incresed at 30 days significantly in the same concentration. In the histological investigation of liver, there was the swelling of hepatic cells at 10 days over the 1.0 mg $kg^{-1}$ dry food concentration. At 30 days Periodic acid-Schiff (PAS) positive granule was observed in the same group and at 20 days was observed in 2.0 mg $kg^{-1}$ dry food group. And there was necrosis of hepatic cell in some fish of 2.0 mg $kg^{-1}$ dry food group at 30 days.

• Fisheries and Aquatic Sciences
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• v.9 no.2
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• pp.91-96
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• 2006

The movement range and diurnal behavior of 17 wild black rockfish (Sebastes schlegeli) were monitored within the marine ranching area of Tongyeong from 27 July to 7 November, 2005 using acoustic telemetry. Coded transmitters were surgically implanted into the abdomen of fish. Two of ten fish released in summer moved about 2 km away from the capture point for 1 day. The others stayed within a 500-m radius of the release point for 1 week after release. The seven fish released in autumn stayed within 500 m of the release point. Most fish were more active and had a greater range of horizontal diurnal movement at night than during the day. Additionally, the range of horizontal diurnal variation was greater in summer than in autumn. While fish released in summer were more vertically active at night than during the day, those released in autumn preferred to move vertically during the day.