• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.5
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• pp.315-326
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• 1991

This study was tried for a mathematical approaches related to daily fluctuations in the stomach fullness of Agrammus agrammus. The specimen was collected by angling and gill net from September 1984 to August 1985 off Shinsudo, Samchonpo. Fullness of the stomachs was increased in the early morning and the late afternoon, decreased in the late morning, at noon, and during the night. That is, feeding activity of the fish was more intense at sunrise and sunset. Daily feeding activity of the fish in a day was divided into the time period of gastric evacuation and both feeding and gastric evacuation. Stomach fullness with the lapse of time in the time period of gastric evacuation was geometrically decreased. Stomach fullness in the time period of both feeding and gastric evacuation was affected by gastric evacuation rates, feeding rates, and maximum fullness of the stomach. These parameters were able to estimate from the method estimating the regression coefficient in the relationship between the time(t) and the stomach fullness$(F_t)$, or between stomach fullness at the time t and $t+\Deltat$. The rates of feeding and gastric evacuation were the highest in spring and the lowest in winter. The relationships between time(t) and stomach fullness$(F_t)$ in the time period of gastric evacuation and both feeding and gastric evacuation induced from hypotheses were respectively as follows. $$F_t=F_{to}e^{-r(t-to)}$$, $$F_t=F\infty-(F\infty-F_{to})e^{-(p+r)(t-{to})}$$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.4
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• pp.357-362
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• 2006

The feeding habits of John Dory (Zeus faber) were studied by examining the stomach contents of 317 specimens collected from January 2004 to December 2005 in the coastal waters off Gori, Korea. The standard length (SL) of the specimens ranged from 12 to 42 cm. Z. faber is a piscivore and consumes mainly teleost fish such as Psenopsis anomala, Trichiurus lepturus and Conger myriaster. Its diet also includes shrimp and cephalopods. Smaller individuals (<25 cm SL) consume shrimp and small fish such as Glossanodon semifasciatus. The proportion of these prey items decreases with increasing fish size, and this decrease is paralleled by increased consumption of lager fish such as Psenopsis anomala and Trichiurus lepturus. The prey size increases with Z. faber size.

• Korean Journal of Ichthyology
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• v.28 no.1
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• pp.9-18
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• 2016

Histological and morphological development of the digestive tract of sevenband grouper were observed from after hatching to 60 days. Fishes were fed with rotifer (Brachionus rotundiformis) and chlorella (Chlorella ellipsoidea) after hatching from 2 to 20 days rotifer and brine shrimp (Artemia salina) in after 20 days rotifer, brine shrimp and semi-dry artificial diet in after 23 days. Histological and morphological development of ten larvae was observed by paraffin embedding method after fixing in 10% neutral buffered formalin. Sevenband grouper RLG showed characteristics of carnivorous fish by average 0.87. Larvae after hatching can't open the mouth and anus digestive tract was observed in a straight line following yolk sac. Larvae was observed feeding activity by opening the mouth and anus. Metamorphosis started 8 days after hatching. Esophagus divided four layer, and goblet cell was observed in esophagus, mid intestine and rectum. Larvae started cannibalism and it was caused by difference of growth. The inside of stomach was differentiated to cardiac orifice, body of stomach, pyloric stomach, and pyloric caeca. Goblet cell was observed all intestine. Gastric gland differentiated after hatching 28 days in stomach. Secretion of gastric juice was found at stomach and mucosal fold pyloric caeca. Even thought the inside of stomach expended and the number of gastric gland increased consistently and goblet cell in intestine and mucosa became longer, histochemical changes follow couldn't be found during transforming juveniles 38 days after hatching.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8815-8822
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• 2014

Background: The incidence of stomach cancer in India is highest in the state of Mizoram. In this population based matched case-control study, we evaluated the relationship between CYP450 2E1 RsaI polymorphism and risk of stomach cancer taking into considering various important dietary habits along with tobacco, alcohol consumption and H. pylori infection status. Materials and Methods: A total of 105 histologically confirmed stomach cancer cases and 210 matched healthy population controls were recruited. CYP2E1 RsaI genotypes were determined by PCR-RFLP and H. pylori infection status by ELISA. Information on various dietary, tobacco and alcohol habits was recorded in a standard questionnaire. Results: Our study revealed no significant association between the CYP2E1 RsaI polymorphism and overall risk of stomach cancer in Mizoram. However, we observed a non-significant protective effect of the variant allele (A) of CYP2E1 against stomach cancer. Tobacco smokers carrying C/C genotype have three times more risk of stomach cancer, as compared to non-smokers carrying C/C genotype. Both Meiziol and cigarette current and past smokers who smoked for more than 10 times per day and carrying the (C/C) genotype are more prone to develop stomach cancer. Smoke dried fish and preserved meat (smoked/sun dried) consumers carrying C/C genotype possesses higher risk of stomach cancer. No significant association between H. pylori infection and CYP2E1 RsaI polymorphism in terms of stomach cancer was observed. Conclusions: Although no direct association between the CYP2E1 RsaI polymorphism and stomach cancer was observed, relations with different tobacco and dietary risk habits in terms of developing stomach cancer exist in this high risk population of north-eastern part of India. Further in-depth study recruiting larger population is required to shed more light on this important problem.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.843-850
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• 2013

The feeding habits of Lycodes tanakae Eelpout were studied with 722 specimens collected from March 2011 to December 2012 in the coastal waters of the middle East Sea. The main prey of L. tanakae were fish, molluscs and arthropods. Nevertheless annelida, echinodermata and others were found in small amounts in the stomach contents. The L. tanakae stomach was empty of contents in 50.9% of specimens. While smaller size specimens of L. tanakae (less than 40 cm) fed mainly on euphausiids and amphipods, the larger specimens (more than 40 cm) fed on the fish Allolepis hollandi and Icelus cataphractus, and the molluscs Berryteuthis magister and Watasenia scintillans. The main prey items of L. tanakae varied seasonally. The fish Lycodes nakamurai was the dominat prey from November to January during its spawning season. Euphausiids and amphipods of the arthropods were the dominant prey from February to April. The molluscs Berryteuthis magister and Watasenia scintillans were the dominant prey from May to September. The diversity index (H') of diets showed variations by length class and month; the highest values were 2.61 in the length class of 51-55 cm, and the monthly highest were 2.68 in September with 23 species and 2.65 in November with 18 species. The highest dominance index (D') of diets was 0.57 in the length class of 31-35 cm, and the monthly highest was 0.71 in February. Cluster analysis divided prey groups into four groups by length class and three groups by monthly prey items. The gonad index gradually increased during the process of maturation while, contrary, stomach content index decreased during this period.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.684-688
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• 2011

The feeding habits of Paralichthys olivaceus in the Uljin marine ranching area, located on the mid-eastern coast of Korea, were studied from January to November 2009. In total, 381 specimens were collected; fish ranged in size from 15.4 to 59.0 cm in total length. P. olivaceus is a carnivore, mainly consuming other fishes and crustaceans. The prey items of P. olivaceus changed ontogenetically. Small individuals fed on decapod crustaceans while large ones fed heavily on other fishes. The diet of P. olivaceus varied seasonally. Fish comprised the main prey items throughout the year. The stomach contents index (SCI) of each size class increased and the dietary breadth index (DBI) of each size class decreased as individuals grew.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.95-104
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• 1997

Stomach contents of 518 specimens of the yellow goosefish, Lophius litulon caught by the off-shore stownet in the southern waters of Korea were examined by means of the calculation of the frequency of occurrence number and weight percentages, and index of relative importance (IRI) in each prey organisms. Prey organisms of the yellow goosefish consist of fishes, crustaceans, cephalopods. Fishes were dominant prey group, and occupied $98.8\%$ in IRI of prey organisms. Four species of fish, Pseudosciaena manchurica Collichthys niveatus, Engraulis japonica, Trichiurus lepturus were dominant as to the IRI and occupied $87.2\%$ of the total IRI. P. manchurica was a dominant prey organism in predator's stomach through the year, and the other dominant prey organisms occurred intermittently with seasonal progress. P. manchurica was a dominant prey organism to all fish size, too. C. niveatus and E. japonica decreased in importance in the diet as the fish size increased concomitant with an increase in importance of T. lepturus. Mean species number and mean individual number of prey organisms increased with the fish size.

• Korean Journal of Veterinary Service
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• v.45 no.4
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• pp.331-335
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• 2022

A yellow-billed spoonbill kept at the zoo was found dead. As a result of the necropsy, the stomach (gizzard and proventriculus) and duodenum were full of undigested fish bones, and the undigested sharp fish bones were lodged in the gastric mucosa and clumped together, blocking the lumen. Thereafter, the intestinal wall was perforated and peritonitis occurred causing death. The cause of the fish spines becoming lodged in the gastrointestinal tract is unknown. It can only be assumed that there was a lack of a mechanism for the yellow-billed spoonbill in a zoo to go around and pick up grit or small stones and assist in mechanical crushing in the gizzard.

• Journal of fish pathology
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• v.31 no.2
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• pp.123-129
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• 2018

Parvicapsula anisocaudata, a myxosporean parasite, is presumably one of causative agents of emaciation in olive flounder Paralichthys olivaceus in Korea. In this study, we report a case of unusual abdominal distension due to exceptionally enlarged liver in farmed olive flounder. For the identification of the causative agent, bacteria and nucleic acids of virus that are possibly present were attempted to isolate from internal organs of five fish sampled from a fish farm in Jeju. Although a few bacterial colonies were isolated from some samples, there was no evidence that fish were primarily affected by virus and/or bacteria. From histopathological analysis, myxosporean were found in almost all internal organs, particularly in the stomach. The causative agent was identified as P. anisocaudata by sequencing a part of small subunit rRNA. This study contains a very unusual case of olive flounder heavily and systemically infected with P. anisocaudata, showing excessively enlarged liver with a small amount of ascitic fluid.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.47-62
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• 1969

A goby, Synechogobius hasta (Temminck et Schlegel) was studied to investigate the food consumed and the biological change of the food organisms, and the fish were sampled from the closed tributary and the lower Part of the Naktong River, near Pusan, during the period from November of 1967 to December of 1968. The fish were sampled from four stations (Fig. 1), the total number of fish being 1,295 and they were grouped and analysed monthly. The content of the alimentary canal was analysed in three categories according to modified Nilsson's method (Dahl 1962) with a slight alteration: 1) The number of each item of stomach contents was counted and the percentage of each item in proportion to the total number of food organisms is indicated by the letter 'N' representing numerical percentage in Table 2. 2) The percentage of fish which contained any items of food organisms in proportion to the total number of fish caught in a given season is indicated by the letter 'O' representing frequency of occurrence. 3) Dominant groups of food items were selected and the percentage of the number of each dominant item in proportion to the number of the food organisms belonging to the dominant groups is indicated by the letter 'D' representing dominance. All food organisms were classified in 50 food item categories and then they were grouped in 13 main groups (Fig. 2-1), and they were further divided into 1) obligatory bottom animals, 2) organic drifts and 3) actively swimming forms; according to the conditions of the animal communities within the habitat. Since the majority of its food was composed of the obligatory bottom animals ($94.6\%$), the fish appeard to be a typical bottom feeder. And the dominant food organisms of the fish is generally determined by the local composition of the benthic fauna within the fish habitat. And their seasonal rhythm occurs among the food organisms in the stomach by the biological interaction. Locality variation in the population of the same food organism occurs due to the difference of food organisms in the habitat of the fish at Seonam and Garak, and at Seongsan and Hadan the condition of the niche for the fish in the both regions seems to be the same since the composition and the seasonal variation of the organisms were the same. The results may be summarized as follows: 1) The goby mainly feed on the animals of bottom fauna, and the food organisms are deter-mined by the food compositions within the habitat. 2) Seasonal variation of the stomach content shows the seasonal rhythm due to the biological variation of the population and their interaction. 3) The goby shows no preference on specific food, and the food is composed of a variety of animals. 4) Major food items of the goby are Polychaeta, Palaemon modestus, Isopoda, Gammaridea, Insecta (nymphs and larvae), Ilyoplax deschampsi, and Paratye compressa. 5) Logitudinal succession oil the population of the food organisms is apparently recognized within the community of Seongsan, Garak and Seonam. 6) The goby begins to descend toward the estuary and sea around April when the water temperature reaches $20^{\circ}C$, and they begin to return to river waters in September.