• Title/Summary/Keyword: 위내용물 조성

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Feeding Habits of Hairtail, Trichiurus lepturus (갈치 (Trichiurus lepturus)의 식성)

  • Huh, Sung-Hoi
    • Korean Journal of Ichthyology
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    • v.11 no.2
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    • pp.191-197
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    • 1999
  • Stomach contents of hairtail, Trichiurus lepturus collected in the Nakdong River Estuary were examined quantitatively. T. lepturus was a carnivore which consumed mainly fishes, crustaceans (such as copepods, euphausiids and shrimps) and chaetognaths. Its diets included small quantities of small squids. T. lepturus showed ontogenetic progression of three feeding stages : an initial feeding stage was a planktivorous stage in which copepods were the major food item, followed by a mixed feeding stage in which euphausiids, mysids, shrimps, chaetognaths and fishes were the major food items, and finally a piscivorous stage in which fishes were the major food item. Especially anchovies were heavily selected by large T. lepturus.

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Feeding Habits of Acentrogobius pflaumii in the Eelgrass(Zostera marina) Bed in Kwangyang Bay (광양만 잘피밭에 서식하는 줄망둑(Acentrogobius pflaumii)의 식성)

  • Huh, Sung-Hoi;Kwak, Seok-Nam
    • Korean Journal of Ichthyology
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    • v.10 no.1
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    • pp.24-31
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    • 1998
  • Feeding habits of Acentrogobius pflaumii collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. Acentrogobius pflaumii was a carnivore which consumed mainly gammarid amphipods, polychaetes and gastropods. Its diets included minor quantities of cope pods, tanaids and crabs. It showed ontogenetic changes in feeding habits. Individuals of 1~2cm SL preyed heavily on gammarid amphipods. However, polychaetes and gastropods were selected with increasing fish size. Although gammarid amphipods, polychaetes, and gastropods were major prey organisms for all seasons, the relative proportion of these food items changed with season. Consumption of gammarid amphipods and polychaetes was relatively high in summer, and consumption of gastropods was relatively high in winter.

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Feeding Habits of Acanthogobius elongatus from the Kunsan Coast Intertidal Zone, Neacho-do in the West Coast of Korea (군산연안 내초도 조간대에 서식하는 왜풀망둑 Acanthogobius elongatus의 섭식생태)

  • KIM Jong-Yeong;NOH Yong-Tai
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.3
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    • pp.413-422
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    • 1997
  • To know the food chain of an intertidal community, feeding habits of Acanthogobius elongata were studied by analyzing stomach contents. A. elongata were monthly collected and the environment conditions of the habitat were investigated in the intertidal zone of Naecho-do, Kunsan from July 1993 to June 1994. Ratio of stomach contents to weight of A. elongata was $1.78\%$, and fullness of stomach showed a similar value to ratio of stomach contents to weight. Fullness of stomach was increased twice a day in the morning and the afternoon. The most important food item was copepods amounting to $54\%$ of the total stomach contents. Of these, Paracalanus parvus was most abundant in spring, Calanus sinicus in summer, Acartia sp. in autumn, and Calanus sinicus in winter. Degree of overlapping for the food items between seasons was not very high, except between spring and summer. There were little differences in feeding habits among the size groups. For all size groups of A. elongata, the occurrence rates of copepods, decapods, molluscs and cirriped larvae were high. As the fish grows, those of amphipods, polychaete larvae, isopods, cumaceans and stomatopods increased gradually. The importance index of the major food items was in the order of Calanus sinicus, Corycaeus affinis and Acartia sp..

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Effect of Length of Maternal Diet Intake on Production of Newborn Rats with Brain n-3 Fatty Acid Deficiency: Pre-pregnancy Method vs. Use of Time-pregnant Animals (엄마 쥐의 식이 섭취기간이 뇌의 오메가 3 지방산 결핍 동물 생성에 미치는 영향: 임신전 단계 실험식이 섭취 방법 vs 임신동물을 이용하는 방법)

  • Lim, Sun-Young
    • Journal of Life Science
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    • v.16 no.6
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    • pp.942-948
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    • 2006
  • This study was performed to determine whether the length of the feeding of the controlled experimental diet to the dam resulted in changes to the dam milk or pup brain fatty acid composition. As a first method, females have been obtained at 3 weeks of age and fed the experimental diet throughout their growth to adulthood including mating, pregnancy, and lactational periods. As a second method, in order to shorten this long and expensive process, time-pregnant dams were obtained as early as possible from a commercial supplier, on day 3 of gestation, and immediately switched to the experimental diet. At birth, the milk of dams prepared by these two different methods was compared by collecting the stomach contents of the pups. This showed a slight increase in docosahexaenoic acid (DHA) and arachidonic acid (AA) in the pup stomach contents from the time-pregnant dams. There were no significant changes in the brain fatty acid composition of pups between the two different lengths of the experimental diet intake. By the 10 days of age, there were only minor differences in the milk fatty acid composition of pup stomach contents from the two sets of dams. However, the pup brains of the time-pregnant groups at 10 days showed increased AA and DHA due to intake of the chow diet including AA, DHA and eicosapentaenoic acid (EPA). Thus, the history of the maternal feeding could affect the results under these particular circumstances, but the differences were minimal.

Comparison of Stomach Contents of Pacific Cod (Gadus macrocephalus) in Korean Coastal Waters (우리나라 연안에 서식하는 대구(Gadus macrocephalus)의 위 내용물 비교)

  • Park, Chung Youl;Gwak, Woo Seok
    • Korean Journal of Ichthyology
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    • v.21 no.1
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    • pp.28-37
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    • 2009
  • The diet of Pacific cod (Gadus macrocephalus) in the East Sea, Yellow Sea and Jinhae Bay was studied by analysis of stomach contents. In total, 518 individuals ranging from 15.5 to 77.0 cm standard length SL were analyzed. Prey organisms of the Pacific cod in the East Sea consistedof Caridea, Cephalopoda and Pisces, whereas In the Yellow Sea, the main food items of Pacific cod were similar to those of East Sea Pacific cod except for Cephalopoda. Interestingly, the stomach contents of Pacific cod in Jinhae Bay is mainly Pisces, which is in contrast to those of the two different coastal areas, the East Sea and the Yellow Sea. Although various species of food were eaten by smaller Pacific cod, both Caridea and Pisces were mainly taken by larger Pacific cod. Consequently, the diet of Pacific cod within acertain size is mainly influenced by prey abundance and prey-size spectrum in its habitat. Higher stomach emptiness of Pacific cod in Jinhae Bay might indicate that fully matured Pacific cod temporally stop feeding during their spawning period.

Diet Composition of Spot Nape Ponyfish, Leiognathus nuchalis in the Coastal Waters of Gadeok-do (가덕도 주변해역에 출현하는 주둥치의 위내용물 조성)

  • Jeong, Jae Mook;Park, Joo Myun;Huh, Sung-Hoi;Kim, Hyeon Ji;Baeck, Gun Wook
    • Korean Journal of Ichthyology
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    • v.27 no.1
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    • pp.33-38
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    • 2015
  • The diet composition of Leiognathus nuchalis were studied using 350 specimens collected from October 2010 to September 2011 in the coastal waters of Gadeok-do, Korea. L. nuchalis was carnivorous feeder that consumed mainly copepods, crab larvae, and shrimp larvae. Its diet also included small quantities of polychaetes, amphipods, euphausiids, bivalve larvae, and gastropod larvae. The size of L. nuchalis ranged from 3.0 to 9.8 cm in body length (BL). L. nuchalis underwent an ontogenetic dietary shift. 3~5 cm size individuals fed mainly on copepods. 5~7 cm size individuals fed mainly crab larvae and shrimp larvae. 8~10 cm size individuals fed mainly polychaetes. The size increases, the weight of food organisms are constantly increased.

The Gut Content Analysis of Polypedilum scalaenum in the Large-scale Weirs of 4 Major River Ecosystems (4대강 보에 서식하는 삼지창무늬깔따구(Polypedilum scalaenum) 위 내용물 분석)

  • Na, Young-Kwon;Jo, Hyunbin;Park, Jae-Won;Chang, Kwang-Hyeon;Kwak, Ihn-Sil
    • Korean Journal of Ecology and Environment
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    • v.53 no.1
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    • pp.55-62
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    • 2020
  • Chironomidae widely utilize as a biological indicator that has various types of feeding pattern such as omnivorous, herbivorous and carnivorous. Polypedilum scalaenum is known as omnivorous, it plays an important role in the food chain of freshwater ecosystems in Korea. Nevertheless, detailed information about diet items of P. scalaenum is still lacking. The purpose of this study is to identify the gut and intestine contents of items on P. scalaenum inhabiting the large-scale weirs of the four major river ecosystems(Ipoh Weir, Sejong Weir, Juksan Weir, Gangjeong-Goryeong Weir, and Dalseong Weir). Phytoplankton was dominant diet items among the study sites. However, zooplankton (i.e. appendages, setae) only found in Ipoh Weir. The phytoplankton species composition in the study sites was correspond to the diet items in the gut and intestine contents of P. scalaenum. In summary, analysis of P. scalaenum gut and intestine contents in this study was able to identify the feeding characteristics of omnivorous Chironomidae, and in particular, it was possible to study the species composition of basic producers in the surrounding aquatic environment by analyzing the contents of the digestive tracts.

Feeding Habits of the Sandfish, Arctoscopus japonicus in the East Sea, Korea (한국 동해에서 채집된 도루묵(Arctoscopus japonicus)의 식성)

  • Lee, Hae Won;Kang, Yong Joo;Huh, Sung-Hoi;Baeck, Gun Wook
    • Korean Journal of Ichthyology
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    • v.19 no.1
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    • pp.44-50
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    • 2007
  • The feeding habits of sandfish, Arctoscopus japonicus were studied by examining the stomach contents of 2,115 specimens collected between April 2003 and March 2004 in the East Sea of Korea. The standard length (SL) of the specimens ranged from 9.8 to 22.9 cm. The main prey items of A. japonicus were amphipods, mysids, cephalopods and fishes. They showed ontogenetic changes in feeding habits. Individuals of small size (9~16 cm, SL) fed mainly on small prey organisms such as mysids and amphipods. However, more cephalopods and fishes were consumed with increasing fish size (16~23 cm, SL).

Diet Composition of John Dory Zeus faber in the Coastal Waters of the South Sea, Korea (한국 남해 연안에 출현하는 달고기(Zeus faber)의 위내용물 조성)

  • Choi, Yu Jeong;Kim, Yeonghye;Lee, Jeong Hoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.54 no.4
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    • pp.526-531
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    • 2021
  • The diet composition of john dory Zeus faber, was investigated using 266 specimens collected in the coastal waters of the South Sea, Korea. The specimens ranged in total length (TL) from 12.5 to 43.2 cm. The Z. faber fed mainly on Pisces and less often on Macrura. We further analyzed the data by dividing the specimens into five classes (<15.0 cm, 15.0-20.0 cm, 20.0-25.0 cm, 25.0-30.0 cm, ≥30.0 cm). The Z. faber diet shifted with size class from predominantly consuming Macrura to Pisces. The proportion of Macrura consumed decreased with increasing body size, whereas the consumption of Pisces increased gradually.

Diet Composition of Oriental Bonito (Sarda orientalis) in Coatal Waters of Jeju Island, Korea (제주도 주변 해역에서 채집된 줄삼치(Sarda orientalis)의 위내용물 조성)

  • Kim, Hyeon Ji;Jeong, Jae Mook
    • Korean Journal of Ichthyology
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    • v.32 no.1
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    • pp.8-13
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    • 2020
  • The feeding habits of oriental bonito (Sarda orientalis) were studied using 288 specimens collected in the coastal waters of Jeju Island, Korea from January to December 2015. Oriental bonito is pelagic piscivore that consumes mainly fishes especially Engraulis japonicus and Scomber japonicus. Its diet also includes small quantities euphausiids, amphipods and cephalopods. Oriental bonito showed ontogenetic changes in feeding habits. Although fishes were the primary food consumed by all size groups, the ratio of fishes was slightly increased as body size increase. There also was a significant relationships between mean prey number and weight according to size class and season.