• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.271-276
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• 1997

The study was attempted to detemine the ratio of stomach and intestine to viscera gathered on catching vessels, the critical level of VBN content as a freshness quality of viscera of Alaska pollack for raw materials of Changran-jeotgal. It also examined the changes of VBN values, pH and viable tell counts during the fermentation. Then sensory evaluation of the fermented products, Changran-jeotgal, was done according to the freshness of raw materials used. The ratio of stomach and intestine to the gathered viscera on the vessel was about $72\%$, while that of round state of Alaska pollack was about $18\%$. There was no significant relationship in VBN content between fish muscle and viscera. It suggests that VBN content is not a reasonable freshness criteria in viscera but in fish muscle. However, if we use the VBN content as a freshness criteria of viscera for raw materials of Changran-jeotgal, less than $70mg\%$ of VBN value could be recommended. According to the experimental results, the product yields and sensory evaluation scores were no good not only for economical evaluation but also for consumption.

• Journal of Aquaculture
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• v.21 no.4
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• pp.278-284
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• 2008

Artificially-produced juvenile black sea bream Acanthopagrus schlegeli (total length $8.3{\pm}1.0\;cm$, body weight $11.2{\pm}4.2\;g$) were released in eelgrass, Zostera marina bed and their initial food organism and changes of body compositions were investigated for one month after release. Predation rates in fish sampled on 1st and 3rd days were 79%, increased up to 100% on 7th and 10th days, and then decreased on 30th days as 75%. Major prey organisms was composed of mainly Amphipoda and Gastropoda. Ratio of Amphipoda and Gastropoda in stomach were highest in fish sampled on 15th and 1st days after release, respectively. Crustacea and Algae were maintained about 20% during a sampling period. Visceral weight index (VWI) offish sampled 20th and 30th after release were significantly higher than that of initial. Carcass crude protein and lipid contents of released fish were showed significantly decreasing; however carcass n-3 HUFA composition was showed increasing tendency with the passage of time after release. Eelgrass bed was supposed to be helpful for the released fish to adjust their feeding habits and biochemical metabolism to the natural environment within a short period after release.

• Korean Journal of Ecology and Environment
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• v.55 no.4
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• pp.368-375
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• 2022

Gut contents analysis is essential to predict the impact of organisms on food source changes due to variations of the habitat environment. Previous studies of gut content analysis have been conducted using traditional methods, such as visual observation. However, these studies are limited in analyzing food sources because of the digestive process in gut organ. DNA metabarcoding analysis is a useful method to analyze food sources by supplementing these limitations. We sampled marine fish of Pennahia argentata, Larimichthys polyactis, Crangon affinis, Loligo beka and Sepia officinalis from Gwangyang Bay and Yeosu fisheries market for analyzing gut contents by applying DNA metabarcoding analysis. 18S rRNA v9 primer was used for analyzing food source by DNA metabarcoding. Network and two-way clustering analyses characterized the relationship between organisms and food sources. As a result of comparing metabarcoding of gut contents for P. argentata between sampled from Gwangyang Bay and the fisheries market, fish and Copepoda were analyzed as common food sources. In addition, Decapoda and Copepoda were analyzed as common food sources for L. polyactis and C. affinis, respectively. Copepoda was analyzed as the primary food source for L. beka and S. officinalis. These study results demonstrated that gut contents analysis using DNA metabarcoding reflects diverse and detailed information of biological food sources in the aquatic environment. In addition, it will be possible to provide biological information in the gut to identify key food sources by applying it to the research on the food web in the ecosystem.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.411-422
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• 1986

Diets of the rock trout, Agrammus agrammus, in the shore area of Tongbaeksom, Pusan over the period of July 1981 to June 1982 were studied. Specimens were sampled by angling. Stomach analysis showed that the rock trout fed mainly on epibenthic food in the littoral zone along the coast of Tongbaeksom. The food organisms of the enviornment were studied by means of underwater sampling around the angling area for this study. Although the food items of the fish changed slightly with season and age-group, main food items were Amphipoda (Gammaridae, Caprellidae) and Isopoda (Sphaeromidae, Idotheidae). This suggests that the diets of A. agrammus mainly comprised epibenthic food. Food diversity increased with age. The fish almost consummed on smaller food in size, but had selective predation according to food size, i. e. on larger food as age increases. These data provide additional support for the importance of the detritus-benthos-consummer type food chain.

• The Journal of the Convergence on Culture Technology
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• v.2 no.4
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• pp.1-21
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• 2016

This article examined the different types of Jeonuhwa as recorded in 16 royal palace studies from the Joseon dynasty (1392-1909). The ingredients used in Jeonuhwa during the Joseon dynasty were categorized as follows: 16.0% for gray mullet(秀魚) and fish(生鮮), 14.2% each for liver and cow stomach, 12.3% for sea cucumber(海蔘), 4.7% each for crab(蟹), clam(生蛤), and chunyup(千葉), 3.9% each for pork meat(豬肉), octopus, 2.8% each for oyster(石花), pheasant(生雉), and chicken(鷄), 2.0% each for croaker(民魚), and brain (骨), 0.9% each for duck(鴨子), pigeon(山鳩), dobi(都飛), snapper, white fish(白魚), mussel(紅蛤), haeran(蟹卵), quail(鶉鳥), egg(鷄卵), and sesame(實荏子). This observation may be associated with commercial industrial development that prevailed during the late Joseon dynasty. Further studies will be conducted on recipes and ingredients recorded in Euigwe in order to develop a standardized recipe for Jeonuhwa.

• Korean Journal of Ichthyology
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• v.20 no.2
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• pp.117-122
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• 2008

The feeding habits of Scorpaena neglecta were studied based on an examination of the stomach contents of 478 specimens collected between January and December 2006 in the Coastal Waters off Busan. The specimens ranged from 9.0 to 23.5 cm in Standard length (SL). S. neglecta is a piscivore and consumes mainly teleosts such as Acropoma japonicum, Coelorinchus multispinulosus, Chaeturichthys stigmatias. Its diet also includes crabs, shrimps, cephalopod and stomatopod. Smaller individuals (<16 cm SL) consume mainly crabs and shrimps. The proportion of these prey items (crabs and shrimps) decreases with increasing fish size, and this decrease parallels the increased consumption of fish. The mean prey size sharply increases between 12 and 20 cm SL of S. neglecta size.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.2
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• pp.160-167
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• 2014

The feeding habits of Tridentiger bifasciatus were studied using 733 individuals collected in the tidal creek at Sangnae-ri, Suncheon, Korea, using a push net, monthly, from April 2011 to March 2012. The standard length (SL) of the specimens ranged from 1.5 to 8.2 cm. The stomach content analysis indicated that T. bifasciatus consumed mainly amphipods, such as Corophium sp., while copepods, polychaetes, and shrimps were other important prey species. In addition T. bifasciatus ate small quantities of crab larvae, fish, gastropod larvae, and insects. T. bifasciatus is a generalist that feeds on various zoobenthos, including fish. T. bifasciatus underwent an ontogenetic dietary shift. Smaller individuals (1-2 cm SL) fed mainly on amphipods. The proportion of amphipods decreased as body size increased, whereas the consumption of polychaetes increased gradually. The seasonal variation in the diet composition of T. bifasciatus was significant. Insects were common prey during summer, while the amounts of other prey, including polychaetes, were similar during spring, autumn, and winter.

• Development and Reproduction
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• v.18 no.4
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• pp.251-258
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• 2014

Serine-arginine-rich nuclear protein LUC7L plays an important role in the regulation of myogenesis in mice. In the present study, we isolated and characterized the Korean rose bitterling Rhodeus uyekii Luc7l cDNA, designated RuLuc7l. The RuLuc7l cDNA is 1,688 bp long and encodes a 364-amino-acid polypeptide containing serine/arginine-rich region at the C-terminus. The deduced RuLuc7l protein has high amino acid identity (71-97%) with those of other species including human. Phylogenetic analysis revealed that RuLUC7L clustered with fish LUC7L proteins. The expression of RuLuc7l mRNA was high in the brain, kidney, and stomach of Korean rose bitterling. Expression of the RuLuc7l mRNA was detected from 1 day post-fertilization (dpf) and moderately increased until 21 dpf during the early development. Further investigations are required to elucidate the functional role of RuLUC7L in myogenesis in R. uyekii.

• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.303-309
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• 2014

Feeding ecology of Collichthys lucidus was determined by analysis of stomach contents of 926 specimens ranged from 3.5 to 18.5 cm in the Han River estuary. This fish actively fed on benthic crustaceans, mainly decapods, Palaemon carinicauda and Acetes chinensis, and they can be defined as the benthivorous predator. The percentage of empty stomachs was 23.8%. The vacuity index (VI) did not vary with the size classes, but showed significant monthly variations. Monthly variation of feeding activity appears to be related to the reproduction cycle of the fish, and to the temporal abundance of the prey organisms. Collichthys lucidus in Han River estuary fed on a wide array of prey items and could be considered as a non-selective predator.

• Korean Journal of Ichthyology
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• v.21 no.1
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• pp.23-27
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• 2009

The feeding habits of Lateolabrax japonicus were studied based on an examination of the stomach contents of 344 specimens collected monthly from January to December, 2005 in coastal waters off Dolsan-do, Yeosu. The standard length (SL) of specimens ranged in 8.7~52.8 cm. L. japonicus is a piscivore that consumes mainly teleosts such as Engraulis japonicus, Trachurus japonicus, and Acanthogobius flavimanus. Its diet also includes Macrura, Amphipoda, Cephalopoda, Polychaeta, Mysidacea, and Branchyura. Small individuals (<25 cm SL) consume mainly Amphipoda and Macrura. The proportion of these prey items decreases with increasing fish size, and this decrease paralleled the increased fish consumption.