• Korean Journal of Ichthyology
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• v.13 no.4
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• pp.223-229
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• 2001

Feeding habits of juvenile Sillago maculata, collected from the tropical seagrass beds in Cockle Bay, Queensland, were studied. S. maculata (0.5~9.5 cm SL) was a carnivore which consumed mainly gammarid amphipods, crabs and copepods. Its diets included small quantities of polychaetes, shrimps, fishes, isopods and cumacean. S. maculata showed ontogenetic changes in feeding habits. Small individuals preyed mainly on copepods, crab larvae and gammarid amphipods. While the portion of the stomach contents attributable to polychaetes, crabs and fishes increased with increasing fish size, consumption of copepods and crab larvae decreased progressively. Gammarid amphipods were the most selected prey item for all size classes.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.435-441
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• 2011

The feeding habits of yellow goosefish Lophius litulon and John Dory Zeus faber were studied by analyzing the stomach contents of specimens collected in the South Sea of Korea. In total, 132 hauls were taken during six experimental trawl survey (Tamgu 1) cruises conducted on a seasonal basis (March 2005-October 2007). The main prey items of the two species were similar. Fishes and crustaceans were the most important prey, with neither species showing ontogenetic changes in preferred species. Specifically, Pennahia argentata was the preferred prey item of L. litulon, whereas Trichiurus lepturus and Engraulis japonicus were preferred by Z. faber. Larger Z. faber (>24 cm) preferred bigger prey such as T. lepturus and Larimichthys polyactis, while smaller Z. faber preferred E. japonicus and Acropoma japonicum.

• Journal of Yeungnam Medical Science
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• v.4 no.1
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• pp.43-47
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• 1987

7 cases of Acute Gastric Anisakiasis have been reviewed at the Department of Internal Medicine. Yeungnam University Hospital from March, 1983 to December 1986. 1. Of 7 cases, the ratio of male and female was 3:4 and the age 30s occupied most (5 cases) the 50s' followed (2 cases). 2. Chief complains were in order of epigastric pain (6 cases), vomiting (3 cases), Nause (2 cases), Ulticaria (1 case) & epigastric fulling sensation (1 case). 3. In all 7 cases, the causative fish is Astroconcer myriaster. 4. The onset of symptoms was observed within 5 to 7 hours after eating the causative raw fish. 5. Gastrofiberscopic exam was undergo within 18 hours since onset of symptoms. 6. The gastrofiberscopic findings were gastric mucosal edema and redness in all 7 cases. One case also had mucosal erosion. The involved sites of the stomach were in frequency of order, the body (5 cases), the antrum (2 cases). 7. The symptoms of the patients relieved spontaneously without medical treatment after the extraction of the larva with biopsy forcep during gastrofiberscopy. 8. In Korea, many people take raw fish and there may be many patients of Anisakiasis so if much concern and careful observation are paid to whom, with severe cramping epigastric pain after taking of raw marine fish in about 10 hours, we could find out and confirm more patients suffering from Anisakiasis by immediate endoscopic gastrofiberscopy.

• Journal of fish pathology
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• v.27 no.2
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• pp.133-137
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• 2014

We examined the cause of a disease outbreak in rainbow trout Oncorhynchus mykiss, which were adapting to a seawater in an aquaculture farm in Jeju on April, 2013. Most of the diseased fish showed a severe ulcer on the skin, enlarged spleen, expanded stomach and hemorrhage of abdominal and pyloric region. Although no parasites, fungi or viruses were isolated from diseased fish, over 200 same bacterial colonies were isolated from liver, spleen and kidney. Nucleotide sequences of the 16S rDNA gene of the bacterium in this study showed 100% identity with Vibrio anguillarum. This study is the first report of V. anguillarum infection in rainbow trout during sea adaption in Korea.

• Journal of fish pathology
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• v.21 no.3
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• pp.247-257
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• 2008

To understand the activity of non-specific defence factors in cultured Sebastes, the antibacterial effect of the serum, skin mucus and homogenate of various organs from cultured oblong rockfish (Sebastes oblongus) and rockfish(Sebastes schlegeli) against pathogenic bacteria, Aeromonas hydrophila, Edwardsiella tarda, Vibrio anguillarum, and Streptococcus sp. was compared with that of flounder(Paralichthys olivaceus) and seabass(Leteolabrax japonicus). And the activities of proteolytic enzyme, chitinolytic enzyme and haemolycin as non-specific defence factor were investigated on the oblong rockfish and rockfish. Samples from oblong rockfish showed the highest antibacterial activity by lysoplate assay on agar plate mixed with pathogens, followed in descending order by rockfish, seabass, and flounder. Turbidimetric assay was carried to evaluate the lysozyme activity of fish samples against lyophilized cells of Micrococcus lysodeiktikus. The serum, kidney, liver, stomach, intestine and eyeball of oblong rockfish and the mucus and gill of rockfish appeared to have the highest lysozyme activity among the fish strains investigated. All samples except skin mucus, liver, and eyeball of oblong rockfish and rockfish showed proteolytic enzyme activity. Chitinolytic enzyme activity was showed in random sampling and haemolytic activity was remarkable in oblong rockfish. Therefore, Sebastes strain was proved to have effective defense mechanisms based on the antibacterial activities, and lysozyme, proteolytic enzyme, chitinolytic enzyme, and haemolycin were considered to act as the non-specific defence factor of Sebastes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.832-839
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• 2014

To evaluate the digestive characteristics and bioavailability of dietary soybean meal (SBM), the post-prandial changes in the gastric contents of rainbow trout Oncorhynchus mykiss were determined for 24 h after feeding of SBM diets. A curve estimation of regression diagnostics using a comparison of the adjusted $r^2$ and probability was performed to test the tendency of the post-prandial changes and gave a quadratic polynomial (exponential) regression for all experimental groups. The gastric evacuations rates (GER) for higher-SBM groups were slower than those for lower-SBM groups. The estimated GER (digestion time) for 75% gastric content for fish fed a 70% SBM diet was 1.63 times longer than that for fish fed the control diet. Despite the fact that the pH values in the gastric contents rose from 4.05 at 0 h to 5.12-5.38 at 1 h after feeding, then dropped to 4.57-4.83 at 9 h, with no significant differences among experimental groups, the gastric moisture contents increased significantly in the higher-SBM groups. This is most likely due to an increase in digestive juices in the higher-SBM groups, rather than water introduced externally. The percentage of soluble nitrogen in the gastric contents of fish fed the higher-SBM diets was higher than that in the fish fed the control diet, and the SBRs (stomach weight/body weight${\times}100$) in the higher-SBM groups (diets 4, 5, 6 and 7) were also significantly higher than the SBR of the control group (P<0.05). This may indicate that the protein in SBM can be digested slowly due to physiological digestive adaptation in rainbow trout.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.642-648
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• 1999

The digestive tract of the black sea bream, Acanthopagrus schlegeli is composed of esophagus, stomach, intestine, anus and four or five pyloric caeca. Pyloric caecum is a blind sac in shape and originated from pyloric portion of the stomach. Relative length of But (RLG), that is length of digestive tract to standard length, is 1.04 (n=10). Histological layer of the digestive tract is composed of serous membrane, muscular layer, undeveloped submucosal layer and mucosal layer. The mucosal folds of the esophagus are regular branched form, Esophageal muscularis mucosae is well-developed. Mucosal epithelial layer is composed of cuboidal or columnar epithelium and mucous secretory cell. Microvilli are absent in the free surface of mucosal epithelium. The mucosal folds of the stomach are regular unbranched form. The stomach has a well-developed muscular layer and muscularis mucosae. Microvilli are present in the free surface of mucosal surface epithelium. The fundic portion of the stomach have a well-developed gastric gland and more numerous secretory granules than the other parts. The mucosal folds of the pyloric caeca and the intestine are irregular branched form, Intestine is divided into the anterior, mid and posterior intestines with length of mucosal folds and histological features, Posterior intestine has a more developed striated border and goblet cells than the other parts. Mid intestine has a more abundant absorptive cells than the other parts in the intestine and pyloric caeca.

• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.318-323
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• 2007

The feeding habits of Pacific cod (Gadus macrocephalus) were studied based on the examination of stomach contents of 192 specimens collected from November, 2005 to January, 2006 in the coastal waters off Gadeok-do, Korea. The size of Pacific cod ranged from 35 to 82 cm in standard length (SL). Pacific cod mainly consumed shrimps such as Eualus spathulirostris, Crogon hakodatei and C. affinis and fishes. Its diet also included small quantities of cephalopods, amphipods, hermit crabs and crabs. Individuals between 35 cm and 45 cm SL mainly consumed shrimps. The portion of shrimps decreased with increasing fish size, and this decrease was paralleled with increased consumption of fishes and cephalopods. In this study we found Syngnathus schlegeli in the stomach contents of many Pacific cod specimens. S. schlegeli is a typical seagrass fish species which inhabits in seagrass beds, This fact means that Pacific cods stay in the seagrass beds during spawning period. Therefore migration of Pacific cod to coastal waters off Gadeok-do during spawning period seems to be a survival strategy for its larvae and small juveniles to stay in seagrass beds which provide with abundant foods and shelters to many commercial fish species.

• Journal of Ecology and Environment
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• v.44 no.1
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• pp.54-61
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• 2020

Background: Most fish undergo prey switch from juvenile to adult. It is thought that slightly different feeding habits occur among adult fishes due to growth, spawning, habitat change, and so on. Therefore, the diet of the John Dory Zeus faber (≥ 24 cm TL) was studied in the coastal waters of Korea by analysis of stomach contents, with comparison by season and size class of diet composition and prey diversity. Monthly samples were taken from February 2017 to January 2018. Results: The results showed that the John Dory was a piscivorous predator, and pisces had occupied 82.3% of IRI%. Trichiurus lepturus and Trachurus japonicus were important preys in all size classes and seasons. Diet composition differed among the size classes and seasons (Chi-square test, P < 0.05). As body size of Z. faber increased, the occurrence of benthic fish (Glyptocephalus stelleri) tended to increase. The seasonal prey composition also changed depending on the abundant species of each season. Conclusions: Z. faber is a piscivorous predator. The consumption habits of Z. faber appear to different results by their size and seasons. This study suggests that Z. faber could be considered an opportunistic predator.

• Korean Journal of Ichthyology
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• v.19 no.1
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• pp.51-56
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• 2007

The feeding habits of bluefin searobin (Chelidonichthys spinosus) were studied based on the examination of stomach contents of 646 specimens collected from January 2005 to December 2005 in the coastal waters off Busan, Korea. The size of C. spinosus ranged from 14.0 to 38.9 cm in standard length (SL). C. spinosus mainly consumed shrimps such as Solenocera melantho, Leptochela sydniesis and Trachysalambria curvirostris. Its diet also included crabs and fishes. Smaller individuals (15~25 cm SL) consumed small shrimps such as L. sydniesis, crabs and fishes. The portion of these prey items decreased with increasing fish size, and this decrease was paralleled with increased consumption of lager shrimps such as S. melantho and Trachysalambria curvirostris. The prey size increased with the increase of fish size.