• 한국발생생물학회지:발생과생식
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• 제25권3호
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• pp.157-171
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• 2021

To determine whether the reproductive processes of sea bass, Lateolabrax japonicus, proceed normally after transportation from an outdoor net-cage into indoor tanks, we examined changes in the gonadosomatic index (GSI), histological gonadal tissue, and plasma levels of sex hormones (testosterone and estradiol-17ß) during their annual reproductive cycle. We also measured maturation and spawning across two sea water salinity levels (full and low salinity). Fecundity was estimated by the relationship between egg number and body size in female sea bass. Monthly changes in the GSI, histological gonadal tissues, and oocyte size showed both male and female sea bass reach final maturation in January and February, respectively, indicating that the spermiation of males occurs earlier than the spawning of females. The histological results indicated that the sea bass is a multiple spawner, similar to many marine teleosts, exhibiting group-synchronous oocyte development. Female maturation and spawning were enhanced in lower salinity seawater (29.6-31.0 psu) compared to that of normal salinity (34.5-35.1 psu). These results confirm that sea bass reproduction can occur successfully in captivity and imply that fertilized eggs can be collected from February to March. Additionally, our results show that lower salinity enhances oocyte maturation and spawning of female sea bass.

• 한국수산과학회지
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• 제27권3호
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• pp.272-281
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• 1994

양식 농어에 대한 사료 carotenoids의 대사와 체색개선에 미치는 영향을 검토하기 위하여 ${\beta}$-carotene, lutein ester, astaxanthin, astaxanthin monoester 및 astaxanthin diester의 첨가사료로서 8주간 사육하여 표피의 carotenoid성분을 분석, 비교 검토한 결과는 다음과 같다. 농어 표피의 carotenoid색소는 tunaxanthin획분과 lutein이 주성분을 이루고 있으며, 그 외 ${\beta}$-carotene, a-cryptoxanthin, zeaxanthin 및 ${\beta}$-carotene type triol이 소량으로 존재하였다. 한편, 천연산은 양식산에 비하여 tunaxanthin과 lutein의 함유비가 높은 반면 ${\beta}$-carotene의 함유비가 낮은 경향을 보여 서로 차이를 보였다. Carotenoid의 축적율은 astaxanthin monoester 첨가구에서 가장 높게 나타나서 체색선명화의 효과가 컸었으며, 그 다음으로 astaxanthin, astaxanthin diester첨가구의 순으로 나타났다. 사육시험후 각 시험구의 carotenoid함량과 조성으로 보아, 농어의 carotenoid대사경로는 astaxanthin이 ${\beta}$-carotene type triol, zeaxanthin, lutein을 거쳐 tunaxanthin으로 되는 환원적대사과정을 가지는 것으로 추정할 수 있었다.

• 한국양식학회지
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• 제11권3호
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• pp.345-352
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• 1998

조피볼락 Sebastes schlegeli 자어와 점농어 Lateolabrax sp. 자어를 대상으로 기아시 성장과 간세포 핵 크기 변화를 조사하였다. 전장과 습중량 성장에 있어 조피볼락과 점농어의 간세포 핵 크기는 첫 먹이 섭취 자어의 영양상태와 연관성을 보였다. 본 연구의 조피볼락과 점농어 자어에서의 기아시 간세포 핵 크기 조사 결과는 조피볼락과 점농어에서 초기 영양상태 판명의 지표가 될 수 있으며 초기 먹이 공급 공정시 내생적 영양상태에서 외생적 영양상태로의 효율적 전환을 가능케 할 것으로 사료된다.

• 한국수산과학회지
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• 제48권6호
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• pp.920-928
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• 2015

This study aims to reveal the relationship between growth of young sea bass and environmental variables in two adjacent eelgrass beds. Fishes were collected from Gamak Bay (GB) and Yeoja Bay (YB) on the southern coast of Korea from February 2006 to February 2007 using a dragnet (15 m in length and 3 m in width). During the study period, a total of 367 individuals of young sea bass Lateolabrax japonicus were collected from GB (171 inds.) and YB (196 inds.). Significant differences were observed in the occurrence periods and growth patterns of young sea bass, as well as in environmental variables between GB and YB. Young sea bass were collected from April to December in GB, but from April to July in YB. These differences may be associated with differences in eelgrass density, leaf width, and zooplankton density between GB and YB.

• 한국양식학회지
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• 제16권1호
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• pp.31-36
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• 2003

사육 염분의 급성교환 실험에서, 해수의 담수화가 1시간 이내에 이루어졌을 경우 농어, 유어들은 다소의 스트레스 반응과 이온의 변화가 있었으며. 24시간 뒤에도 정상 회복이 더딘 것으로 나타났다. 그러나 5시간에 걸친 담수화 과정 중에 스트레스 반응은 담수화 직후 높게 나타났지만, 24시간 후 빠르게 정상으로 회복되는 것을 알 수 있다. 장기간 염분별 사육실험 결과, 20 ppt가 가장 높은 사료섭식량을 나타내었고, 2 ppt구가 가장 낮았다. 사료효율 또한 2 ppt구이 가장 낮게 나타났고, 10 ppt구가 가장 높았으며, 실험구별 유어의 성장은 실험 종료시 10, 20 및 30 ppt구가 2 ppt보다 유의하게 높은 길이 성장을 보였다. 무게 성장은 실험 종료시 20 ppt가 가장 빠른 무게 성장을 나타내었고, 다음으로 30 ppt, 10 ppt. 2 ppt순으로 나타났다. 염분별 사육유어의 혈액 성상은 2 ppt~30 ppt 사육수에 있어 농어 유어들의 혈액 조성은 큰 차이가 없는 것으로 나타났다.

• 한국수산과학회지
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• 제56권5호
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• pp.651-659
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• 2023

The effect of bio-logger tagging location on blood characteristics and bio-logger attachment efficiency in spotted sea bass (mean body weight 2356.7 g) was investigated. The fish were tagged at four different tagging locations: no-tag (control), operculum attachment (OA), dorsal muscle attachment (DA), and cauda peduncle muscle attachment (CA). The blood properties and bio-logger attachment efficiencies were examined on days 1, 7, 14, and 35 after tagging the bio-logger at each tagging location. During the experimental periods, the concentrations of hematocrit and hemoglobin in whole blood, and GOT (glutamic oxaloacetic transaminase), GPT (glutamic pyruvic transaminase), total protein (TP), glucose, total cholesterol, cortisol, and superoxide dismutase in plasma were not affected by the attachment location of the bio-logger, however, the TP concentration was significantly lower in OA than in the control group on day 7. After tagging for 35 days, the efficiencies of bio-logger attachment in the OA, DA, and CA after tagging for 35 days were 33.3%, 100.0%, and 33.3%, respectively. These results indicate that, in our experimental condition, the most appropriate bio-logger attachment location is DA, providing basic information on bio-logger utilization methods for ecological and biological biotelemetry surveys of the spotted sea bass.

• 수산해양기술연구
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• 제17권1호
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• pp.1-6
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• 1981

The selective response of the sea bass, Lateolabrax japonieus and the gray rock cod, Sebastes inermis to the colored twines was studied in a white tiled aquarium C400LX60WX70H em), by use of Y -maze made of gray plastic plate. Anyone of the different colored twines, white, black, blue, yellow and red, was strung crosswise on a rectangular frame which was mounted to one of the two outlet ends of Y -maze, and another colored twine was used to the other end of the Y -maze. In each trial, a fish was guided toward the inlet of the Y -maze to let the fish select either one of the two different colored twines. The results obtained are aS follows: 1. Sea bass preferably selected the colored twines in a order of white, blue, yellow, black and red with significant difference. 2. Gray rock cod showed little difference in selecting colored twines even though the fish selected white one a little more frequently.

• 한국식품영양과학회지
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• 제29권5호
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• pp.777-782
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• 2000

To investigate the effects of growth and body composition of spotted sea bass (Lateolabrix sp.) by the supplemented dimethyl-$\beta$-propiothetin(DMPT). fish was fed the diets each containing 3 mM, 5 mM, 7 mM and 10 mM for eight weeks. The weight gain, feed efficiency and feed intake were significantly increased with dietary DMPT level. Condition factor was reduced by dietary DMPT supplementation. Crude protein content of fish after eight weeks increased with dietary DMPT level, whereas crude lipid content deceased with dietary DMPT level. Amino acid content was higher in DMPT-added group than control group. Amino acid composition was not influenced by dietary DMPT supplementation. Fatty acid content deceased with dietary DMPT level.

• 수산해양기술연구
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• 제42권3호
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• pp.158-168
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• 2006

A study on the species composition and seasonal variations of fishery creatures caught by a funnel net was carried out in the coastal water off Dolsan Island, Yeosu from 2002 to 2003. During the study period, a total of 23 fishery creatures species were caught. Seabream(Acanthopagrus schlegeli), sea bass(Lateolabrax japonicus), mullet(Mugil cephalus), puffer(Takifugu niphobles) and rockfish(Sebastes inermis) predominated. These five species accounted for 85.1% of the total number of fishery creatures caught. Seasonal peaks of number of species occurred in summer, while those of number of individuals occurred in autumn. The lowest number of species and individuals were observed in winter. The large annual variation of diversity indices were observed from May to August. These large annual variation of diversity indices were mainly due to predominance of seabream, sea bass and mullet which accounted for most of all fishery creatures caught. The seasonal variations of fishery creatures showed that sea bass and mullet were caught mainly from spring to summer, seabream and puffer were caught mainly in autumn, and rockfish and brotula(Hoplobrotula armata) were caught mainly in winter.

• 한국어병학회지
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• 제22권2호
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• pp.163-166
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• 2009

The ectoparasite ciliate Trichodina has been recorded from above 100 species of freshwater and marine fishes. In April 2009, we investigated the trichodia infection in 13 species of marine fishes captured by emplacement net and gill net in order to understand trichodina infection status among the natural fish populations along the Namhae-Gun coast area, the southen coast of Korea. Trichodina infection was observed in 10 out of 10 sea basses Lateolabrax japonicus, 2 out of 5 finespotted flounder Pleuronichthys cornutus and 1 out of a stone flounder Kareius bicoloratus. The sea bass infected with the parasite showed hypertrophy and exfoliation in gill epithelium. In addition, hyperplasia and lamellar fusion of gill filament were noticed among naturally affected sea bass.