• Journal of Food Hygiene and Safety
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• v.7 no.2
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• pp.101-105
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• 1992

There is increasing awareness of the devastating socio-economic cost of cardiovascular disease. As a result there have been a lot of extensive researches both on basic mechanisms involved and on the areas of epidemiology and clinical trials. Now it is being generally accepted that dietary n-3 fatty acids abundant in marine products, may reduce the incidence of cadiovascular disease. Fish oil . with its complement of n-3 fatty acids, has been shown the have diverse and sometimes potent actions on cells of the blood and vasculature, which may explain some of its positive effects on vascular disease. However, the appropriate intake of n-3 fatty acids has not been established. This may vary with desired effects, the duration of ingestion, the type of seafood or fish oil and amount of other fatty acids, especially n-6 fatty acid being consumed in the diet. Although the beneficial effects have been extensively studied, little is known about potential adverse effects with excessive intake of n-3 fatty acids. Thus, it is needed to study on the possible unfavorable effects including genetic effects.

• 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.

• 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.21 no.6
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• pp.17.1-17.7
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• 2018

This study investigated the trend in emaciation infection outbreak in olive flounder (Paralichthys olivaceus) of Jeju island, South Korea, during 2014-2015. A total of 900 fish were systematically examined by PCR method using the EM-F/EM-R primer set in April, May, September, November, and December 2014, and the infection rate was recorded. In 2015, the same examination was conducted in March, May, July, and October but with 660 fish. It was found that the infection rate was 18.3~71.6% in 2014, which increased to 16.3~90.3% in 2015. Furthermore, September and December in 2014 and March, July, and October in 2015 showed a relatively higher infection rate. According to the infection trend analysis, which depended on the sample size, the infection occurred in all of fish sizes in this study and 11~30 cm fish group showed the highest infection rate. Histological examination confirmed that the kidney areas of the emaciating infected olive flounder contained several spores of $4{\sim}9{\mu}m$, and in severe cases, the elimination and destruction of tissue were confirmed by PCR. Thus, an important portion of farmed olive flounders in the Jeju region suffers from emaciation disease. This epidemiological survey serves as a useful reference on the emaciation disease of cultured olive flounders in Jeju

• Korean Journal of Ecology and Environment
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• v.52 no.4
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• pp.306-315
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• 2019

The estuary of the Han River constantly suffers from pollutants and pathogenic microorganisms which could cause serious damage to aquatic organisms living there. Despite of this potential risk, it is hard to find any reliable scientific reports on the status of reportable disease infection to the organisms living in this area. In this study, cyprinid fish and crustaceans in Jeonryu-ri, a region of the Han River estuary, were investigated for the infection by representative reportable communicable diseases(SVC, spring viraemia of carp; KHVD, koi herpesvirus disease; EUS, epizootic ulcerative syndrome; WSD, white spot disease) and parasites. Peripheral fish and primary freshwater fish were observed in Jeonryu-ri with cyprinid caught most frequently. Crustaceans were mostly marine species. No positive bands to any of the reportable diseases were produced in any of the fish and crustacean examined in this study by PCR. No trace of Clonorchis sinensis, a liver fluke potential threat to human health, was detected in any of fish samples. However, many fish were infected by metacecaria of other flukes, and other various parasites such as nematode, cestode, copepod, monosite and acanthocephalan. These results suggest that important aquatic organisms in the Han River estuary is not seriously polluted yet. However, it is important to keep monitoring the diseases since the water quality in this region is constantly changing, and devastating influence of infectious diseases is unpredictable. Further, it is required to expand monitoring area toward upstream and increase the number of fish for examination.

• Journal of fish pathology
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• v.23 no.2
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• pp.155-163
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• 2010

The epidemiological study was performed to survey the prevalence of fish pathogens in cultured olive flounder, Paralichthys olivaceus from 2005 to 2007. In this study, the fish pathogens were detected from 1,528 among 2,238 fish samples collected yearly in 5 sites from February, May, August and November. Annual incidences for three years show a yearly increase and there were 60.6% in 2005, 66.7% in 2006 and 72.3% in 2007, respectively. Seasonal prevalence was 63.5% in February, 67.4% in May, 75.1% in August and 64.4% in November for three years. The detection rates of 6 viral pathogens were 35.6% in 2005, 44.6% in 2006 and 24.4% in 2007 and the peak rate was 55.4% at adult size group (above 41cm). Viral nervous necrosis virus (24.7%) has been the most predominant virus in this investigation, while much lower rates were noted in viral haemorrhagic septicemia virus (10.6%) and red sea bream iridovirus (0.9%).

• Journal of fish pathology
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• v.23 no.3
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• pp.369-377
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• 2010

The epidemiological study was performed to survey the prevalence of fish pathogens of cultured olive flounder, Paralichthys olivaceus collected in Pohang, Ulsan.Gijang, Keoje and Wando area of Korea from 2005 to 2007. In this study, the fish pathogens were detected from 1,528 among 2,238 fish samples and annual incidences were 60.6% in 2005, 66.7% in 2006 and 72.3% in 2007, respectively. Seasonal prevalence was 63.5% in February, 67.3% in May, 75.1% in August and 64.2% in November for three years. The detection rates of parasites, bacteria or viruses were 36.7%, 32.8% and 31.4%, respectively. 775 cases (34.6%) among 2,238 fish samples showed mixed infection with a different pathogens. The distribution of specific diseases showed that detection rates of diseases occurring the most frequently during the study period were Trichodina spp., (28.2%), viral nervous necrosis virus (24.3%), Vibrio (11.6%), viral hemorrhagic septicaemia virus (10.5%).

• 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.7 no.2
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• pp.105-112
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• 1994

A new bacterial infection occurred among the cultured Korean catfish, Silurus asotus, in Chunbuk prefecture, Korea, 1993. This disease produced about 30% mortality in the fish for 4 months. The diseased fish was swimming listless at the water surface with head up and tail down, sometimes spinnig in circles. The most outstanding clinical sign was ulceration on the skull and at the base of the pectoral fins. The causative organism was isolated from the brain, kidney, spleen and liver of diseased fish, and identified as Edwardsiella icaluri by the biochemical and biophysical characteristics. After intraperitoneal innoculaton of the isolate, the pathogenicity was proved positive for Korean catfish, S. asotus, and channel catfish, Ictalurus punctatus, but negative for carp, Cyprinus carpio.

• Journal of fish pathology
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• v.31 no.2
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• pp.87-92
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• 2018

A case of disease was occurred in tiger puffer, Takifugu rubripes, reared in circulated system (water temperature was about $20^{\circ}C$) on land in Korea. Diseased fish showed a unique external sign, the cloudy skin ulcer in various sizes. We investigated the cause of disease, and isolated one pure cultured bacterium, TP01. This had 99.7% homology with Vibrio atlanticus by sequence analysis of the 16S rRNA and rpoA genes. TP01 showed some differences with other reported V. atlanticus strains in the biochemical characteristics as like Voges-Proskauer test and gelatin hydrolysis.