• Journal of Marine Life Science
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• v.7 no.1
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• pp.45-51
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• 2022

The profer salinity range for aquaculture of hybrid grouper (Epinephleus bruneus♀ × Epinephleus lanceolatus♂) were evaluated in terms of their survival, growth, feed intake and physiological responses after 30 days of exposure to different salinities (0 psu, 3 psu, 5 psu, 10 psu, 15 psu, 20 psu, 25 psu, 30 psu). Hybrid grouper all died at 0 psu salinity on the 4th day of exposure but all hybrid survived at a salinity of 5 psu or higher during the exposure period. Body length and weight increased above 5 psu salinity and the growth rate was the highest at 30 psu. Hybrid exposed to 3 psu did not eat the feed pellet. Feed intake did not show a significant difference between salinity 20 psu, 25 psu and 30 psu. Plasma osmolality of the juvenile hybrids exposed to different salinities was 341~368 mg Osmol/kg above 5 psu. The oxygen consumption rate was the highest at 30 psu with 163.6±22.3 mg O₂/kg fish/h. SOD, CAT and GSH-PX were significantly higher at 15 psu. Therefore, the critical salinity for survive of the juvenile hybrid was 5 psu, and the proper salinity for optimal culture was analyzed with 20~30 psu.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.53-63
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• 2021

Age structure and growth of white croaker Pennahia argentata were estimated an analysis of otoliths. Fish specimens were collected from the Southern Sea of Korea from January to December 2018. A thin section method was used for age determination because otoliths of white croaker are oval in shape and large in size. Otoliths were cut vertically into 0.4-0.5 mm thick sections with an electric saw (Micracut 125). Monthly changes in the marginal index indicated that rings (opaque zone) were formed once a year in August. The estimated von Bertalanffy growth equation estimated by a non-linear regression were L∞=34.71 (1-e0.38(t+0.80)). In the present study, the oldest female was 8 years old and the male was 7 years old.

• Korean Journal of Environmental Biology
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• v.41 no.3
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• pp.298-307
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• 2023

The annual reproductive cycle of two species, Upogebia major (de Haan 1841) and Austinogebia wuhsienweni (Yu 1931), of the female mud shrimp from the west coast of Korea was investigated using histology. The collected samples were divided into adult and juvenile groups to understand the mature period of age class based on the carapace length(CL). Juvenile Upogebia(CL<25mm) were mostly inactive gonad with early (62%-100%) and late (10%-38%) development stages during the year, whereas the adult shrimp showed a seasonal pattern of gonad maturation(CL≥25 mm). The early and late developmental stages of oocytes were observed in adult Upogebia from November to March and mature eggs appeared from April to October. In adult Ausitnogebia (CL≥15 mm), fully grown oocytes were consistently observed during the study period, in which the ripe stage was found between January and June. On the other hand, most juvenile Austinogebia (CL<15 mm) maintained an immature state in the gonad. Both species of the mud shrimp reproduced from ovigerous females in the adult population and their egg-bearing period was distinguished from January to April for U. major and from July to September for A. wuhsienweni.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.2
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• pp.224-228
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• 2022

The feeding habits of the Pacific herring Clupea pallasii were examined based on 333 specimens collected from the coastal waters of the East Sea of Korea. Sampling was conducted in April, June, and September 2019 and February 2020. The total length of the C. pallasii ranged from 11.9 cm to 37.7 cm. Euphausiids (93.0%, index of relative importance, IRI), especially Euphausia, comprised the primary diet of the pacific herring, in addition to amphipods, copepods, and fishes. The dietary composition of C. pallasii showed non-significant differences by size. As body size of C. pallasii increased, the mean number of preys per stomach (mN/ST) and the mean weight of preys per stomach (mW/ST) tended to increase.

• The Science & Technology
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• v.11 no.1 s.104
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• pp.38-40
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• 1978

일본은 1979년에 완공을 목표로 차성현에 자성현에 축파연구학원도시를 건설중에 있다. 이미 과학기술청 산하의 무기재질연구소 국립방재과학기술센터 환경청 산하의 국립공해연구소(본지1977년 6월호에 소개) 문부성 산하 고에너지 연구소 축파대학등이 이전신설을 완료하여 새로운 연구원도시로서 활기를 대기 시작하고 있는데 시년에는 농림성 관계 연구기관의 이전이 본격화 되고 있다. 즉 열대농업기술연구센터,식물바이러스연구소의 개소에 이어 과수실험장,농업토목연구소,임업실험장이 가까운 시일내에 전시설의 정비를 끝내고 개소할 예정이며 금년도에는 식품종합연구소, 가축위생실험소가 그리고 내년도에는 농업기술연구소,축산기술연구소,단사실험장, 농사실험장의 일부가 이전할 예정이다. 이 이외에도 농림성의 과수화목과 축파분실(가칭)과 농림수산기술회의 사무국의 일부도 입주할 것이라 한다. 용지 총면적은 474.5핵터, 건물용지는 227.4핵터에 이르고 있다. 이들 농림성 산하 연구기관이 집중된 지역을 흔히 농림단지라고 부르고 있다. 이번에는 최근 식물 바이러스 연구소를 중심으로 농업단지를 소개한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.849-860
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• 2021

This study investigated the preparation of seasoned anchovy sauce (SAS) and its functional characteristics by using aminopeptidase active fractions (AAFs) derived from squid Todarodes pacificus hepatopancreas as a bitter taste improver. As the base of the SAS, a hydrolysate (AAAH) prepared by continuously treating raw anchovies with Alcalase-AAF was used. The high-performance liquid chromatography profile of the AAAH suggested that the action of AAFs decreased the hydrophobicity of the N-terminal peptide related to bitterness in the protein hydrolysates. SAS was prepared by blending with the AAAH and other ingredients. The crude protein (2.5%), carbohydrates (18.4%), amino acid-nitrogen (1,325.1 mg/100 mL), and total free and released amino acids (FRAAs, 700.2 mg/100 mL) of SAS were higher than those of commercial anchovy sauce (CAS). Sensory evaluation revealed that SAS was superior to CAS in flavor, color, and taste. The main FRAAs of SAS were glycine (16.8%), alanine (13.2%), glutamic acid (7.8%), and leucine (7.3%). The amino acids that had a major influence on the taste according to the SAS taste values were glutamic acid, aspartic acid, alanine, and histidine. The angiotensin-converting enzyme inhibitory (2.21 mg/mL) and antioxidant activities (3.58 mg/mL) of SAS were superior to those of CAS.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.518-527
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• 2020

The aim of this study was to define the toxic effects of diuron and irgarol, which are new-antifouling agents, on the fertilization rate and normal embryogenesis rate in the sea urchin, Hemicentrotus pulcherrimus. In addition, the study was intended to confirm the hindrance of development in sea urchins. The fertilization rate of H. pulcherrimus was not decreased by the tested concentrations. However, the normal embryogenesis rate was decreased in a concentration-dependent manner. The 50% effective concentrations (EC₅₀) of normal embryogenesis rate were 7.12 mg L^-1 and 2.31 mg L^-1, respectively. As the embryos developed into pluteus larvae, after 18 h of exposure to diuron and irgarol at EC₅₀, development of the early gastrula stage was delayed, and significant developmental delays were observed after 24 h. After this, continuous developmental delays were observed in the process leading to the early gastrular, gastrular, early pluteus, and pluteus stages. Therefore, the toxic effects of diuron and irgarol on sea urchins were attributed to the delay in the developmental processes in the early life stages. Diuron and irgarol are highly persistent in the environment and have known-well toxic effects on various marine organisms including invertebrates, as shown in this study. Therefore, it is urgent to establish an environmental protection strategy to prevent the pollution of and preserve the marine environment.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.11 no.3
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• pp.124-132
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• 2006

We have investigated morphological development with growth and survival rates of juvenile for 158 days after parturition to get a basis data in the way of establishment of breeding techniques in the common seahorse species of Barbour's seahorse, Hippocampus barbouri. At 1 day after parturition, seahorse larvae were $8.82\sim10.36mm(mean\;9.48{\pm}0.69mm,\;n=4)$ in standard length (SL) with 17 dorsal fm rays, 14 pectoral fin rays and 4 anal fin rays. At 20 days after parturition, the size of seahorse larvae were $14.37\sim15.79mm(14.97{\pm}0.62mm,\;n=4)$ in SL, snout of seahorse larvae became slender was long, and body was coloration to the full as adult seahorse. At 41 days after parturition, seahorse larvae were grew $20.14\sim24.89mm(22.89{\pm}2.22mm,\;n=4)$ in SL with development of several spines in coronet, and their have 11 trunk rings and 35 tail rings. At 158 days after parturition, seahorse were grew to $59.07\sim63.76mm(61.42{\pm}3.32mm\;n=2)$, and head length (HL), trunk length (TrL) and tail length (TaL) were composed respectively $19.1{\pm}0.3%,\;25.2{\pm}0.7%$ and $55.8{\pm}0.3%$ of SL. In this time, survival rate is 15.6%.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.321-327
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• 2019

This study aimed to compare on sensory and nutritional characteristics between seasoned Laver Pyropia yezoensis with concentrates of octopus Octopus vulgaris cooking effluent (SL-COCE) and commercial seasoned laver (C-SL). Proximate composition of SL-COCE was significantly higher in moisture and ash, lower in lipid than those of C-SL. However, there was no differences in protein between seasoned lavers (P<0.05). The SL-COCE was stronger in sensory appearance, taste, flavor and texture than the C-SL. The SL-COCE was higher in mineral (Ca, P, K, Fe and Zn) than the C-SL. Total amino acid content of SL-COCE was slightly higher than that of C-SL. The major amino acids of SL-COCE were aspartic acid, glutamic acid and alanine. Mineral content based on the 100 g of SL-COCE was 272.3 mg in calcium, 392.2 mg in phosphorus, 1,025.8 mg in potassium, 10.6 mg in iron, 4.4 mg in zinc, which was higher than C-SL. Total content of fatty acid per the 100 g of SL-COCE was 35,098 mg, which was lower than C-SL (39,679 mg). The major fatty acids of SL-COCE were 16:0, 18:1n-9 and 18:2n-6.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.3
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• pp.239-248
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• 2022

This study was conducted to compare sensory and nutritional and digestive properties of the Israeli carp Cyprinus carpio muscle (ICM) by size [normal large (NLF) and small (NSF) fish], part [ventral (VM) and dorsal (DM) muscle], and commercial value [NLF, recessive (RF) or deformed (DF) fish]. In NLF, the major amino acids were lysine, aspartic acid, and glutamic acid, whereas aspartic acid and glutamic acid were predominant in NSF, DM, VM, DF, and RF. Taurine content increased with fish size, and was higher in DM than in VM, and higher in NLF than in DF but lower than that in RF. Regardless of ICM size, part, and commercial value, potassium and iron were expected in the health function, but calcium and zinc were not expected. The major fatty acids present in ICM were 16:0, 18:1n-9, and 18:2n-6, regardless of size, part, and commercial value. The digestion rate of ICM by digestive organ was lower in NLF than in NSF, and lower in VM with a high lipid content than in DM, and lower in DF than in RF.