• 한국양식학회지
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• 제12권4호
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• pp.309-315
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• 1999

In order to understand the initial feeding time of larvae red marbled rockfish, Sebastiscus tertius changes of mouth size were investigated. Also, the fecundity of different size of red marbled rockfish broodstocks was measured. The broodstocks of red marbled rockfish, S. terius of $32.3\pm6.52 cm$ and larger than 45cm in total length spawned 296,648 and 600,000 larvae, respectively. About 50% was normal healthy larvae among the spawned ones. Mouth sizes calculated by the angle mouth opening and upper jaw length for newly spawned red marbled rockfish larvae were 0.263, 0.197 and 0.132 mm at D, 0.75D and 0.5D, respectively, when the upper jaw length was 0.186mm. Thereafter, 20 days old larvae showed 0.822, 0.617 and 0.411 mm in calculated mouth length at D, 0.75D and rockfish larvae grows, their upper jaw length gradually increased. 2 days old red marbled rockfish larvae possibly stated to feed rotifers and lasted their feeding for the another 35days, relatively long periods compared with other larvae fish. And 25 days old larvae possibly fed the newly hatched Artemia nauplii and lasted their feeding for the another 20 days, like other larvae fish. The proper supplying time of artificial feeds for the red marbled rockfish larvae seemed to be around 10 days after spawning.

• 한국어병학회지
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• 제32권2호
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• pp.81-89
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• 2019

As an epidemiological survey, mortality of marbled rockfish, Sebastiscus tertius observed from a fish farm in Gyeongnam province of South Korea. The major macroscopic sign of the diseased fish was severe multifocal dermal ulceration. Histological observation revealed inflammation, necrosis and colonization of bacteria in various tissues (gill, liver, spleen and kidney). Bacteria was isolated from spleen and kidney in moribund and mortality fish. Seven bacterial isolates from the diseased fish were identified as Aeromonas salmonicida subsp. salmonicida using API 20E and 20NE, API 50CH API ZYM system. Under light microscopy, infected marbled rockfish showed the lifting of the lamella epidermal layer, edematous changes and hypertrophy of epithelial cell in the gill filament. The atrophy of the mucosal fold, erythema in the intestine, and the necrosis of hematopoietic tissue and renal tubule cells with karyolysis were observed in the kidney. In this study was demonstrated the histological reaction of red marbled rockfish infected by Aeromonas salmonicida. Furthermore, this is the first account of extensive dermatitis in Sebastiscus tertius due to atypical A. salmonicida infection, which has high potential in aquaculture among native fish species.

• 한국양식학회지
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• 제12권3호
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• pp.213-220
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• 1999

This study was performed to investigate the effects of water temperature and stocking density and rotifer density on the mass production of larval red marbled rockfish, Sebastiscus tertius. Total length of the marbled rockfish larva grown in $23^{\circ}C$ of water temperature were 10.80mm, which was the best, while those grown in $29^{\circ}C$ of water temperature were 6.28mm, which was the lowest. The survival rates of red marbled rockfish larvae grown in $20^{\circ}C$ and $23^{\circ}C$ were 24.0% and 18.5%, respectively. However, the survival rate of red marbled rockfish larvae grown in $26^{\circ}C$ was $7^{\circ}C$ and no larvae survived in $29^{\circ}C$. The total length of red marvled rockfish larva stocked at the density of 5 and 10 larvaper liter of water were high, which were 11.52 mm and 11.22 mm, respectively, but those stocked at the density of 30 larva per liter of water were 7.55mm, which was the lowest. The survival rate of red marbled rockfish larva stocked at the density of 2.5 larva per liter of water was 52.0%, which was the best, but the lowest, 18.0% for the red marbled rockfish larva stocked at the density of 30 larva per liter. There was a trend toward decrease in survival rate of red marbled rockfish larva as their stocking density increased. The survival rates of red marbled rockfish larva fed rotifers at the density of 10 and 5 individuals per ml were high, 48.5% and 48.0%, and their total lengths were 11.92 and 11.89mm, respectively, which grew relatively fast. The survival rate and the total length of red marbled rockfish larva fed rotifers at the density of 30 individuals per ml were the lowest, which were 8.40mm and 21.5%, respectively. Also, red marbled rockfish larva fed rotifers at the density of more than 20 individuals per ml achieved poor survival and growth. These results indicated that the proper conditions for the mass production of larval red marbled rockfish were $23^{\circ}C$ of water temperature, fish larva stocking density of 5 to 10 larva per liter of water and rotifers density of 5 to 10 individuals per ml as live feed.

• 한국발생생물학회지:발생과생식
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• 제18권3호
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• pp.133-137
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• 2014

Rearing experiments were conducted using several regimes combined with different photoperiods and water temperatures to investigate the role of temperature and photoperiod as environmental cues regulating reproduction in red marbled rockfish, Sebastiscus tertius. The initial gonadosomatic index (GSI) was $1.62{\pm}0.32%$ and that in the $15^{\circ}C$ control was $7.01{\pm}0.46%$ at the end of the experiment. The highest GSI was $9.10{\pm}0.35%$ in the 12L:12D photoperiod-treated fish. The highest GSI at $19^{\circ}C$ was $15.03{\pm}0.86%$ in the 12L:12D photoperiod treatment. The initial hepatosomatic index (HSI) was $3.09{\pm}0.72%$ and that in the $15^{\circ}C$ control was $3.88{\pm}0.45%$. The highest HSI was $4.00{\pm}0.56%$ in the 15L:9D treated fish. The highest HSI at $19^{\circ}C$ was $4.05{\pm}0.63%$ in the 12L:12D treated fish.

• 한국수산과학회지
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• 제44권6호
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• pp.701-708
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• 2011

The aim of the present study was to analyze the reductive cycle of the red marbled rockfish Sebastiscus tertius. The analysis was based on annual changes in the gonadosomatic index (GSI), the hepatosomatic index (HSI), histology of the gonadal structure, and plasma sex steroid hormone levels of adult fish from April 1997 to April 1998. GSI of females began to increase in February and peaked ($10.8{\pm}2.72$) in May. HIS levels ($3.41{\pm}0.49$) peaked in February and elevated plasma steroid hormones ($1.47{\pm}0.75$ ng/mL for estradiol-$17{\beta}$ ($E_2$) and $230.7{\pm}27.6$ pg/mL for testosterone (T)) were observed in April. However, in male fish, GSI levels started to increase in August and remained high until November ($0.21{\pm}0.05$). T levels were was also elevated in August and peaked in October ($188.1{\pm}43.5$ pg/mL) and November ($186.8{\pm}28.0$ pg/mL), but started to decline 1 month than the GSI. These results suggest that female ovoviviparious periods span from April to June and amle mating periods occur from November to February.

• 기술사
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• 제32권6호
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• pp.120-129
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• 1999

• 한국양식학회지
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• 제12권1호
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• pp.15-24
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• 1999

1997년 1월부터 5월까지 전라남도 완도 연안에서 연승어업에 의해 채집된 붉은쏨뱅이 어미들을 육상수조로 운반하여 체내에서 수정된 난을 인위적으로 채란하여 난의 형태를 관찰하였고, 산출자치어의 성장에 따른 형태변화를 관찰하였다. 1. 붉은쏨뱅이의 수정란 및 미수정란은 구형으로 무채투명하여, 이경은 0.72~0.80mm(평균 0.75mm, n=50)이고, 큰 유구 하나와 작은 유구 2~7개가 분포한다. 2. 산출직후의 자어는 전장이 3.79~3.97mm이며, 입과 항문이 열려있고, 눈에 색소포가 착색되어있다. 3. 산출 1~2일째의 자어는 전장이 3.90~4.13mm으로 난황을 완전 흡수하여, 아래턱에 처음으로 흑색소포가 출현한다. 4. 산출 11일째 자어는 성장이 4.23~4.60mm으로 가슴지느러미에 9~10개의 줄기가 출현하며, 후두부에 나뭇가지모양의 흑색소포가 나타난다. 5. 산출 21일째 자란은 전장이 5.83~7.10mm으로 통색말단이 $45^{\circ}$ 각도로 굽어진다. 6. 산출 33일째 개채의 전장은 9.80~12.36mm으로 모든 지느러미 줄기가 정수에 달하여 치어기로 이행한다.

• 현장농수산연구지
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• 제13권1호
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• pp.115-129
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• 2011

붉은쏨뱅이의 인공종묘생산을 위하여 자어의 성장과 생존에 영향을 미치는 초기먹이생물의 영양학적인 측면과 수질안정을 위한 첨가물들의 농도에 대하여 조사하였다. 영양가치가 다른 먹이생물로 rotifer를 배양하여 자어에게 공급하였을 때 농축 Chlorella로 배양된 rotifer를 공급하였을 때 전장의 성장이 11.90 mm로 가장 좋았으며 생존율은 유지효모로 배양한 rotifer를 공급한 실험구가 47.0 %로 가장 높게 나타났다. Rotifer를 영양강화 시킨 후 먹이로 공급하였을 때의 super selco로 영양강화시킨 실험구에서 전장과 체중이 각각 13.0 mm, 12.7 mg로 가장 좋은 성장을 보였으며 생존율도 48.0 %로 가장 높게 나타났다. Artemia의 경우는 다른 실험구와 성장차이는 보이지 않았으나 생존율에서는 super selco로 영양강화한 실험구에서 비교적 높게 나타났다. 먹이종류에 따른 자어의 성장은 rotifer+Artemia+배합사료를 공급한 실험구에서 전장과 체중이 각각 18.4 mm와 18.1 mg으로 가장 좋았고, 생존율에 있어서는 rotifer+Artemia 실험구가 57.5%로 가장 높게 나타났다. 물만들기는 Chlorella 농도가 10×10⁵ cells/ml인 실험구에서 전장과 체중 성장이 각각 11.83mm와 14.3mg로 나타나 가장 효과적이였던 것으로 나타났으며 생존율은 20×10⁵ cells/ml 실험구에서 54.5%로 가장 높게 나타났다 PSB의 첨가 효과는 PSB 농도가 15×10⁵ cells/ml 실험구에서 전장과 체중이 각각 13.98mm와 13.15mg으로 가장 좋았으며 생존율은 PSB 농도 10×10⁵ cells/ml 실험구에서 61.0 %로 가장 높게 나타났다.