• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.411-416
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• 2009

Proximate compositions and fatty acid profiles of cultured and wild mackerel (Scomber japonicus) muscles were compared. Protein content ranged from approximately 16% to 18% and was higher in wild fish than in cultured ones. Lipid content was between two to four times higher in large and small cultured fish (20.1-20.5%) compared with same sized wild fish. The prominent non-polar lipid (NL) class in fish muscles was triglyceride, and additionally, free sterol was among the prominent NL classes in wild fish muscles. Prominent phospholipid (PL) classes in cultured and wild fish muscles were phosphatidylethanolamine and phosphatidylcholine, with the former being higher in cultured fish and the latter higher in wild fish. Prominent fatty acids of total lipid were 16:0, 18:1n-9, 22:6n-3 (docosahexaenoic acid, DHA), 20:5n-3 (eicosapentaenoic acid, EPA), 16:1n-7, 18:0 and 14:0, while 18:2n-6 was among the prominent fatty acids in cultured fish. The n-3 polyunsaturated fatty acids (PUFA, DHA+EPA) content (in mg/100 g of muscle tissue) was higher in cultured fish (2,711 mg in large fish and 2,572 mg in small fish) than in wild fish (2,431 mg in large fish and 1,398 mg in small fish). In conclusion, we have been able to demonstrate that cultured mackerel could also be a good sources of n-3 PUFA, such as DHA and EPA.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.2
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• pp.141-147
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• 2008

Acoustic telemetry technique is one of useful tools to get behavioral information of the free-swimming fish. In this study, we conducted acoustic telemetry using coded acoustic transmitters to compare behavior characteristics between wild and cultured black seabream Acanthopagrus schlegeli, one of target species to promote resource in the marine ranching area. Two wild fish and five cultured fish were released in the marine ranching area after tagging surgically. Three of cultured fish were domesticated using the remote acoustic conditioning system for 3 weeks before being released. Two wild fish stayed at the released point for 2 hours and 9 days, respectively. One of wild fish was found about 10.8km away from the released point after 5 months. Two cultured fish stayed at the released point for 6 days and 75 days, respectively. One of acoustic conditioned fish stayed at the released point for 131 days and then was found about 10.1km away from the released point after 25 days. Others stayed at the released point during this study period(159 days).

• Journal of fish pathology
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• v.25 no.2
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• pp.77-84
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• 2012

Various antibiotics, that could induce the appearance of resistant microorganisms, have been used for treatment or prevention of bacterial diseases in marine and ornamental fish. We determined and characterized the level of antibiotic-resistant bacteria and proportion of multi-drug resistant bacteria in intestinal microflora of both marine fish cultured in Korea and imported ornamental freshwater fish. For this the bacterial species and resistance to antibiotics were investigated in intestine of rock bream Oplegnathus fasciatus cultured in Korea and pearl gourami Trichogaster leeri imported from Singapore to characterise. Although the bacterial species were different, proportions of resistant bacteria to single antibiotics or multi-drug were higher in intestinal microflora of pearl gourami Trichogaster leeri imported from Singapore than in rock bream Oplegnathus fasciatus cultured in Korea. These results indicate that various antibiotics have been being used before trading without measures in the market of asian ornamental fishes, providing high risks for the emergence of multi-drug resistant bacteria.

• Fisheries and Aquatic Sciences
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• v.3 no.2
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• pp.118-125
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• 2000

Lipid classes and fatty acid compositions of eight species of wild and cultured seawater fish in Korea were investigated. Total lipid (TL) contents of wild and cultured fish were $2.64\pm1.88\%$ and $5.42\pm1.76\%$, respectively, except for rockfish and striped beakperch. Non-polar lipids (NL) in all fish samples comprised approximately $84\%$ of the TL content. The proportion equation of NL content to TL content was y=0.9296x-0.4468 $(R^2=0.98l2, p<0.001)$. The most abundant NL class was triglyceride. The prominent fatty acids in all fish samples were 16: 0, 18: 1(n-9), 22 : 6(n-3) (docosahexaenoic acid, DHA), 16: 1(n-7), 20 : 5 (n-3) (eicosapentaenoic acid, EPA), 18 : 0 and 18 : 1(n-7). The polyunsaturated fatty acid (PUFA) group was the richest among the total fatty acids (TFA). DHA and EPA were comprised of approximately $85\%$ of n-3 PUFA. There was a positive correlation between TFA content and n-3 PUFA content; y=0.292x-0.0055 $(R^2=0.9349, p<0.001)$. The n-3 PUFA content of the cultured fish was approximately twice as much as that of the wild fish. Therefore, cultured fish were proven to provide better sources of n-3 PUFA if compared to wild fish.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.5
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• pp.539-546
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• 2019

The major cultured marine fishes in sea off the coast Gyeongsangnam-do Province, South Korea, were assessed and included 9.3% rockfish Sebastes schlegelii, 7.8% red seabream Pagrus major, and 2.1% rock bream Oplegnathus fasciatus. The number of insurance payments related to disease mortality in cultured fish in 2017 was fourfold that in 2016. Economic loss in aquaculture due to disease in cultured fish is high and represents an important inhibitory factor affecting marine fishery productivity. In 2018, diseases led to severe production losses in several aquaculture species: 40.0% in rockfish, 11.4% in olive flounder Paralichthys olivaceus, 10.0% in filefish Thamnaconus modestus, and 9.3% in red seabream. Fish-parasitic pathogens such as Microcotyle sebastis, Alella spp., and Dactylogyrus spp. enter mainly via the gills and skin surface. Among bacterial pathogens, Vibrio species were most common, with Vibrio harveyi being the dominant species causing infections in these fishes. The bacterium Lactococcus garvieae is thought to exhibit host specificity in fish. The fish species in the present study exhibited a higher tendency for infection by heterologous pathogens than by a single pathogen; therefore, it is necessary to devise new strategies for treating diseases in cultured fish.

• Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.234-240
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• 2023

Enteromyxum leei has been identified as the causative agent of emaciation disease in a wide range of marine fish hosts. In this study, we aimed to determine the effect of the parasitic infection of Enteromyxum species on starry flounder that were cultured in aquaculture farms of Jeju island in Korea. As the mortality of cultured olive flounder Paralichthys olivaceus because of E. leei infection increased, some fish farms on Jeju island attempted to culture the starry flounder Platichthys stellatus, as an alternative. Myxosporeans with a developmental stage similar to E. leei were found in the intestines of cultured starry flounders. The partial 18S rDNA of myxosporeans showed 100% similarity with E. leei. To reveal the effect of E. leei infection on starry flounder, the intensity of E. leei infection measured using quantitative polymerase chain reaction, and the condition factor (CF) of fish were measured and analyzed statistically. The results showed that high-intensity E. leei infection significantly decreased the CF of the starry flounder. However, the pathogenicity of E. leei to starry flounder is low, considering its mortality and clinical signs.

• Journal of fish pathology
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• v.12 no.1
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• pp.66-69
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• 1999

Occurrences of red sea bream iridovirus disease (RSIVD) in cultured marine fishes were investigated. The infection was detected by the polymerase chain reaction (PCR) used to amplify the red sea bream iridovirus (RSIV). The RSIV infection was widely distributed in fish culture farm around the south coastal area of the Korean peninsula.

• Fisheries and Aquatic Sciences
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• v.23 no.4
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• pp.14.1-14.14
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• 2020

We performed field measurements of the behavioral changes in cultured chub mackerel (Scomber japonicus) caused by tide-induced changes in the shapes of their small-sized tetragonal fish cages. The field measurements were conducted in two separate periods: neap tide, a period in which the shape of the fish cages was stable; and spring tide, a period in which the fish cages are significantly deformed, which was expected to have significant influences on fish behavior. In the spring tide, the cages were deformed greatly by the moving water, with different water velocities affecting the cages to different degrees; the volume loss was estimated at 4.9% and 7.3% for v = 0.114 m/s and v = 0.221 m/s, respectively. The fish exhibited significantly different behaviors between the neap tide and spring tide. During the neap tide, the fish remained in the lower part of the cage, but during the spring tide they made frequent upward and downward movements, and their horizontal distribution changed significantly due to the changes in the shape of the cage. The cage deformation during the spring tide greatly influenced the swimming behavior of fish.

• Journal of fish pathology
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• v.19 no.3
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• pp.215-225
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• 2006

Viral and bacterial pathogens of the wild marine fishes were monitored in 176 wild fish and 15 wild shrimp from 13 and 1 species, respectively, which were captured by a trawl net in the southern sea of Korea during June 2006. Viral pathogens that are common etiologically agents to cultured fish in Korea were not isolated. One and 5 bacterial strains were affiliated to the genus Proteus and Pseudomonas, respectively, but these bacteria do not seem to be associated with mortality of aquacultural fish. An extended monitoring on wild marine fishes were necessary for identification of agents responsible for the cultured fish infections.

• Journal of fish pathology
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• v.12 no.1
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• pp.49-55
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• 1999

To detect birnavirus from cultured marine fish, RT-PCR assay was developed. This method was specific for aquatic birnaviruses that include IPNV Sp., IPNV Ab, IPNV VR-299 and MBV Y6. The birnavirus gene was detected (birnavirus positive samples detected 46/50) from clinical samples signed with abdominal distension and overall darkening even though the samples gave negative results in virus isolation (birnavirus isolate with CHSE-214 cell showed 12/50).