• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.1
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• pp.39-54
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• 2005

Seasonal variation in species composition of fish in the Geum River estuary was determined using monthly samples collected with a bag net from February to December 2003. Of a total of seventy-three species collected, four groups of fishes were distinguished. Estuarine fishes such as Chelon haematocheilus and Synechogobius hasta were collected almost all the seasons and predominated in abundance during cold months. Coastal fish species such as Sardinella zunasi, Konosirus punctatus, Engraulis japonicus, Johnius grypotus and Thryssa kammalensis were dominated from late spring to autumn. Their adults entered into the estuary in spring and a large number of their juveniles were collected in summer and autumn till moving out to deeper waters for over-wintering. A few freshwater fishes were collected when the freshwater was discharged during the rainy season. Anguilla japonica elvers (diadromous fish) and Coilia nasus (amphidromous fish) were collected in spring during their upstream migration. The principal component analysis revealed that the seasonal variation in species composition of fishes was principally determined by water temperature and/or water temperature related factors.

• Journal of Veterinary Clinics
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• v.17 no.2
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• pp.502-504
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• 2000

Epitheliocystis in cultured rock firth was examined Epitheliocystis infected gill epithelial cells resulted in the cells enlarging to 20 to 400${\mu}{\textrm}{m}$ in diameter. Key diagnostic feature is a large, granular, basophilic inclusion. filled with coccoid bodies, which occupies virtually the entire cell.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.917-922
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• 2013

Changes in fishing ground of the large pair trawler were investigated by year, month and species off Korean waters. We used catch data by sea-block lat.${\times}$long.:$30^{\prime}{\times}30$) of the National Fisheries Research and Development Institute (NFRDI) and monthly fishing production statistics of Korean statistic information service from 1990 to 2007. In the 1990s, the demersal fish like Larimichthys polyactis, Collichthys sp, Portunus trituberculatus and Muraenesox cinereus were the dominant species, and in the 2000s, they were changed from demersal fish into pelagic fish like Scomberomorus niphonius, Scomber japonicus, Engraulis japonicus and Todarodes pacificus. Species composition of catch showed temporal variation by cluster analysis deviding into 4 period, 1990-1994, 1995-2000, 2001-2003 and 2004-2007. Fishing ground in the 2000s was decreased up to 2/3 in the 1990s, while the density of catch in the fishing ground in 2000s was higher than the 1990s.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.3
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• pp.197-201
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• 2004

Juveniles of parrot fish (Oplegnathus fasciatus) were graded and divided into three groups (mean initial size): Small group $(32.9\pm3.2\;g),$ Large group $(130.1\pm12.3\;g)$ and Ungraded group $(74.8\pm29.8\;g).$ Growth and sex ratio were monitored over 3 years. It was concluded that no production advantage was gained by weight grading. There were no differences when the pooled data from the two graded groups were compared with the ungraded group, although mean weight and survival of the large group were continuously higher than those of other groups until the end of rearing period. The highest percentage of males was found in the large group. These results show that males start growing faster than females long before the size grading.

• Journal of fish pathology
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• v.25 no.3
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• pp.243-247
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• 2012

Histopathological observations on a epidermal papilloma of wild red halibut (Hippogossoides dubius) caught at the area around Echung Island and Gogunsan Islands were done. The papilloma formed on the dorsal fin was the same color with the body on the ocular side but black on the non-ocular side. Under light microscopy, the tumor on the skin was very similar to epithelial papilloma supported by connective tissue. X-cell-like cells in the tumors were large and eosinophilic with a centrally-located, large nucleus. But the characteristic large nucleolus in the nucleus of the x-like cells was indistinct clear in this specimen because about 6-9 hours have passed after catching the fish and autolysis have occurred.

• The Journal of Fisheries Business Administration
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• v.31 no.1
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• pp.33-54
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• 2000

This study intends to examine the distribution channel of the most popular ten species caught in Korean coastal and off-shore fisheries with the aid of interviewing fish brokers and cooperative staffs in fish landing markets. This paper finds and emphasizes the following three suggestions, in order to improve the present scheme of fish distribution system. Firstly, annual catch of 10 kinds of fishes is successively decreasing in quantity from 1994 to 1998. Moreover annual catch shows larger variations than fish price and cooperative sales quantity. Except sea eel and sole, cooperative sales accommodates more than 90% of the fish landed, accounting for the small variation in cooperative sales, which invalidates the effectiveness of the free distribution system adopted by the government. Secondly, diversified distribution channels are exposed according to the nature of the fish, the method to harvest, and the quantity caught. Large retailers such as discount stores, super chains and home shopping institutions are actively involving themselves in direct purchase in fish landing markets. Through the analysis of distribution routes, the general distribution channel of fresh fish has been found such as producers longrightarrow fish brokers in landing markets longrightarrow fish brokers in central wholesale markets longrightarrow wholesalers longrightarrow retailers longrightarrow consumers. In order to reduce distribution margin through the analysis of distribution function and distribution margin, this paper presents a new distribution channel such as producers longrightarrow fish brokers in landing markets longrightarrow wholesalers longrightarrow retailers longrightarrow consumers. Thirdly, to improve the fish landing markets, this paper suggests the M&A of uneconomical fish landing markets or renovating toward wholesalers, introduction of processing services and improvement of processing facilities, subsidizing fish brokers in landing markets, revitalization of marketing divisions in cooperatives and improvement in fish auction system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.37-42
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• 1981

Ichthyophonus disease broke out among rainbow trout (Salmon gairdneri) fry in November 1979, and after that a fish group containing diseased fish was kept for one year. The authors examined histopathologically the diseased fish 3 times, at 6 momths intervals. Diseased fish showed markedly stunted growth and darkish coloration, and anatomically the liver with small white nodules, the heart with red nodules, the spleen with granular nodules and the markedly tumefied kidney. Ichthyophonus invaded various tissues in the host and took the shape of multinucleate spherical or hyphal body. The multinucleate-spherical bodies contained many nuclei with a large nucleolus and granular cytoplasm. Histopathologically systemic dissemination and systemic proliferation by Ichthyophonus sp. wire indentified. In addition to a single multinucleate-spherical body appeared in the various tissue, large granulomas containing two to several generations of Ichthyophonus sp. were formed especially in the liver, kidey and spleen. The inflammatory response against Ichthyophonus was characterized by mononuclear-celluar proliferation with giant cell formation and fibrobasts proliferation.

• The Journal of Fisheries Business Administration
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• v.46 no.3
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• pp.73-82
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• 2015

This study aimed to evaluate the effectiveness of closed season policy using an integer linear programming, targeting the large purse seine fishery in Korea. In the analysis, based on Cheng and Townsend(1993), fishing effort (fishing days by month) was assumed to be distributed for profit maximization of vessels and catch of immature fish was estimated. The analytical results showed that the effects of closed season policy would vary in accordance with the monthly closures in terms of fishing profits and catch of immature fish. A closed season policy by month had different effects on fishing profits and catch of immature fish by species. It implies the importance of considering seasonal changes of fish species when limiting fishing efforts with the closed season policy.

• Proceedings of the Korean Society of Life Science Conference
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• 2003.10a
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• pp.14-27
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• 2003

The genomes of Arabidopsis and rice have been fully sequenced. Genomic sequencing provides global information about genome structure and organization. A comprehensive research account of our recent studies conducted on genome painting, comparative genomics and genome fusion is provided in order to project the prospects of plant cytogenetic research in post-genomics era. Genome analysis by GISH using genome painting is demonstrated as an excellent means suitable for visualization of a whole genome, since total genomic DNA representing the overall molecular composition of the genome is used as a probe. FISH on extended DNA fibers has been developed for high-resolution FISH and has contributed to determining the copy number and order of genes. We have also mapped a number of genes involving starch synthesis on wheat chromosomes by FISH and compared the position of these genes on linkage map of rice. Macro synteny between wheat and rice can be observed by comparing the location of these genes in spite of the fact that the size of DNA per chromosome differs by 20 fold in two. Moreover, to approach our goal towards making bread and udon noodles from rice flour in future by incorporating bread making and the noodle qualifies in rice, we have been successful in introducing large genomic DNA fragments containing agronomically important genes of wheat into a rice by successive introduction of large insert BAC clones, there by expanding genetic variability in rice. We call this method genome fusion.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.546-552
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• 2007

The objectives of this study were to analyze fish compositions, based on trophic guilds and tolerance guilds and determine community characteristics structure at five sampling sites of Yeongsan Lake during July 2006-May 2007. Total number of species sampled was 30 species and the number was 1350. Cyprinidae (77%) and Centrarchidae (15.7%) dominated the community and then followed by Cobitidae(2.7%), Gobiidae(2.4%), Mugilidae (0.5%), and others (0.1%). The relative abundance of tolerant and omnivore species at all sites was 63% and 77% of the total, respectively, suggesting an ecological degradations in the Lake. Exotics species such as large mouth bass (Micropterus salmoides), which is a top-carnivore in the water distributed at all sampling sites, implying that ecological disturbance was severe based on previous reference of US EPA (1991). Also, we found external anomalies such as external deformities, bleeding and tumors and not found migratory fish. Analysis of fish community structure showed that species diversity index and richness index was the highest in Site 1 and the dominance index was the highest in Site 2. In this study, high proportions of tolerant species and omnivore species, widespread exotic species, and frequent observations of abnormal fish. Such problems may be directly or indirectly associated with high nutrient enrichments and the reduced flow velocity by the dam construction. The ecosystem restoration by dam removal or removal of exotic top-carnivore fish may be one of the best strategies for better lak management.