• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.4
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• pp.344-348
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• 2009

This study was conducted to investigate effects of dietary lipid level on growth and body composition of juvenile red sea bream in low temperatures. Duplicate groups of fish (initial body weight of 79 g) were fed one of three isonitronic diets (47% crude protein) containing different lipid levels (10%, 17% and 22%) for 25 weeks during the winter season. Weight gain and survival of fish fed 17% lipid diet were significantly (P<0.05) higher than those fish fed the 10% or 22% lipid diet. Protein efficiency ratio, daily feed intake, condition factor, hepatosomatic index and viscerasomatic index were not affected by dietary lipid level, but feed efficiency of fish fed 10% lipid diet was significantly (P<0.05) lower than those fish fed the 17% or 22% lipid diet. Proximate composition of the whole body, liver, viscera and dorsal muscle were not significantly different among all groups except for crude protein content of dorsal muscle. The contents of 16:0, 18:0, 20:4n-3 and 20:5n-3 of the whole body were significantly (P<0.05) affected by dietary lipid level. The results of this study suggest that an increased dietary lipid level from 10% to 17% can improve growth of juvenile red sea bream in low temperature periods.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.5
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• pp.353-361
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• 2015

The area of red tides occurences, which brings enormous damages every year, have been expanded to the coastal waters across the nation. Regarding to this trend, the development of red tide detection technology by using the GOCI (Geostationary Ocean Color Imager) of COMS lauched in 2010 has been drawn attentions of researchers. This study purposed on analyzing the frequency and density of red tides occurence by using the GOCI for detecting the southern sea, whereas targeted area. The observation has brought over the last three years (2012, 2013, and 2014) before the analysis was conducted. Followingly, the study could be resulted in extracting and revealing the hot spots of the red tides from two of analysis in the overlay and density. The distribution patterns of red tide occurrences according to those observed years has been shown in irregular characteristics and various changes. However, the analysis of hot spots, based on the frequency of the red tide occurrence, has revealed that the frequency of red tide occurences is continuously increased in the specific sea area. Therefore, it is concluded in that the continuous monitoring can contribute to predict accurate movements of red tides, so as establish systematic plans for preventing disasters.

• Journal of fish pathology
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• v.20 no.3
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• pp.211-220
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• 2007

Red sea bream iridovirus disease (RSIVD) cause massive economic losses in marine aquaculture industry in Korea. The causative agent of this disease (RSIV) infects a wide range of fish species. The aims of this study were to monitor RSIV in wild marine fishes and to give critical information for controling the disease through prophylactic methods. Prevalence of the viral disease, geological distribution and reservoir of the virus were investigated using wild marine fishes captured in southern coast and east china sea for two years. (Polymerase Chain Reaction) PCR results showed that RSIV were detected in 39 (24.3%) out of 160 fish. MCP gene sequences of viral strains isolated in this study were closely related to that of a reference strain, red seabream-K, belonging to Megalocytivirus subgroup Ⅲ. The results suggest that some of wild marine fishes are RSIV carriers and may spread the pathogen directly to fish farmed in coastal area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.2
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• pp.49-62
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• 2001

Hydrographic surveys were carried out seven times during May 31, 1998 and September 24, 1998 in order to study the physical environments of the coastal area between Narodo Is. and Sorido Is. in the southern sea of Korea (the South Sea) where the occurrence of Cochlodinium polykrikoides red tide is frequently observed in summer. Temperature and salinity of the water column from the surface to the depth of 30 m exhibit large seasonal variations. Mean temperature of the water column increased by 6 and mean salinity of the water column decreased by 2.71 psu during the observation period. Both the freshwater supplied from the adjacent land and the precipitation over the study area cannot account for the observed salinity variations. The influx of the low salinity water from the offshore area is considered to be the main cause for the observed salinity changes. Surface salinity in the study area shows different spatial distribution in the period of outbreaking, mid-stage and disappearance of the red tide. Especially, salinity was abruptly lowered at the stage of disappearance of red tide as compared to salinity of the previous observation period. Vertical structure of water properties also became vertically homogeneous at the disappearance stage, while it was highly stratified in the previous observation. Such changes can only be explained by the inflow of low salinity water from the offshore, which is considered as the most possible cause for the disappearance of the red tide in the study area. This study suggests that exchanges of water, and chemical and biological factors between coastal areas and of shore area in the South Sea need to be studied in association with the general circulation of the South Sea in order for the better understanding of the occurrence and disappearance of the red tide in the coastal area of the South Sea.

• Journal of Environmental Science International
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• v.16 no.6
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• pp.745-750
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• 2007

Large scale of loess has been applied on the south - sea shore of the Korean peninsula to treat red tides, due to many fishery's devastation by red tides every year. However, coastal ecosystem is ruined by the huge amount of loess applied every year. Almost all creatures, living under water such as sea weeds, clams, and fishes, where loess was applied, are disappearing. In this paper, alternative methods of the loess application are investigated. The amount of loess could be reduced by the alternative methods, Especially, loess mixed with calcium oxide has excellent effects to reduce Cochlodinium polykrikoides numbers. It was found that when loess is used with calcium oxide(CaO), removal efficiency of red tides is highly increased. Moreover, the amount of loess could be reduced dramatically.

• Journal of Life Science
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• v.10 no.5
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• pp.447-455
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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 red sea bream (Pagrus major). The content of DMPT extracted from Ulva pertusa by auroclaving was 32.5mg%. Body weight gain, feed efficiency and feed intake 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.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2008.11a
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• pp.282-285
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• 2008

At least 15% of the C polykrikoides cells that precipitated to the bottom layer either by the addition of loess or no addition survived for 1 week at all growth phases, rather than disappearing immediately after precipitating. However, no live cells were observed after 20 days, regardless of phase or loess addition. In the exponential phase, the number of C polykrikoides cells increased to >2886 cells/ml after loess was added. However, in the stationary phase, the number of cells did not increase until 18 days. In the exponential phase, those C polykrikoides that survived precipitation caused by scattering loess on cultures did not appear to have the ability to cause red tides again because of the short red tide periods in the field, long lag time after loess addition, and low survival rate after loess addition.

• Journal of Nutrition and Health
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• v.29 no.3
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• pp.278-285
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• 1996

Contents of insoluble(IDF), soluble dietary fiber (SDF), and total dietary fiber(TDF) of 30 foods which are consumed commonly by 80 Koeran male college students were determined by Prosky and colleagues' enzymatic-gravimentric method. Foods with highest intake frequency were rice, Kimch'i, and red pepper powder. TDF, IDF, and SDF contents of rice were 0.96, 0.59 and 0.37g/100g wet wt., respectively and tose of Kimch'i were 3.07, 2.19 and 0.88g/100g wet wt., respectively. Red pepper powder contained high amount of TDF(39.37) and IDF (33.13g/100g wet wt.). The TDF content of the 30 foods ranged from 0.70 to 39.37g/100g wet wt. Red pepper (39.37), dried laver(31.36), and dried sea mustard (37.77g/100g wet wt.) contained high amounts of TDF. The IDF content of the 30 foods ranged from 0.13 to 33.13g/100g wet wt. Red pepper powder (33.13), dried laver(15.55) and sesame(15.43g/100g wet wt.) contained high amounts of IDF. SDF of the 30 foods ranged from 0.01 to 25.66g/100g wet wt. Dried sea mustard(25.66), dried laver(15.81), coffee powder (13.17), and garlic(8.72g/100g wet wt.) were good sources of SDF. % ratio of SDF to TDF of the 30 foods was lower than 50% except soybean curd(94.27%), coffee powder (88.93%), garlic(86.17%), dried sea mustard(67.94%), and dried laver(50.41%). It is recommended to increase intake of seaweeds in order to supply TDF adn SDF properly.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.620-627
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• 2016

A 60-day experiment was conducted to determine the effect of feeding and starvation on the survival, growth, and blood parameters of red sea bream Pagrus major. The starved group was not fed during the first 32 days of the experiment and was then fed for 28 days. The growth rate of the starved fish group was significantly lower than that of the fed fish group. Starvation resulted in growth retardation and reductions in final body weight, growth rate, specific growth rate, and condition factor, whereas the fed fish group grew well and maintained a good condition. The growth rate of the starved group that was refed was higher than that of the fed group. Red blood cells, hematocrit, and hemoglobin showed no significant differences between the fed and starved groups. The cortisol and glucose levels of the fed group of juveniles were higher than those of the starved group. The cortisol levels of the starved group of adults were higher than those of the fed group, whereas the glucose levels of the starved group were lower than those of the fed group. These results suggest that the survival, growth, and hematological parameters used to reflect starvation and feeding in this study provide a useful index of physiological response and survival rate in red sea bream.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.3
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• pp.559-572
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• 2019

In the southeast sea of Korea, the cold water is concentrated in every summer, showing in abnormal oceanic conditions. Cold water occurred in the southeast sea is dominantly influenced by wind, which occurs when the south wind is continuously blowing for 3 to 7 days more. In this study, water temperature, wind speed and direction data of KMA, KHOA and KHNP, Chlorophyll-a of COMS/GOCI, GHRSST Level 4 SST of NASA, and red tide alert data of the National Institute of Fisheries Science were used to analyze the correlation between occurrence and change of the cold water and the red tide of Cochlodinium polykrikoides. The upwelling cold water mass showed a characteristic of moving northward along the current and occurrence a high concentration of chlorophyll along the water mass. Also, when the warm current were strong, the characteristic of red tide showed a northward moving.