• Title/Summary/Keyword: length of feeding

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Feeding habits of Acentrogobius pellidebilis in an eelgrass(Zostera marina) bed (해초지에서 서식하는 점줄망둑(Acentrogobius pellidebilis)의 먹이습성)

  • Kwak, Seok-Nam;Huh, Sung-Hoi;Kim, Ha-Won
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.4
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    • pp.358-367
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    • 2010
  • Feeding habits of Acentrogobius pellidebilis collected from in an eelgrass(Zostera marina) bed from January to December 2006 were studied. A. pellidebilis ranged form 1.6 to 6.9 cm in standard length were determined. A. pellidebilis was a carnivore which consumed mainly copepods, polychaetes, and amphipods. Its diets included small quantities of isopods, seaweeds, nematods, and gastropods. It showed ontogenetic changes in feeding habits. Smaller individuals (<2.0cm SL) fed mainly on copepods. While the consumption of copepods decreased with increasing fish size, the consumption of polychaetes and amphipods were increased. Dietary breadth index was varied with fish size.

Feeding Habits of Sebastes thompsoni in the Coastal Waters off Busan, Korea (부산 주변 해역에서 채집된 불볼락(Sebastes thompsoni)의 식성)

  • Huh, Sung-Hoi;Nam, Ki-Mun;Choo, Hyun-Gi;Baeck, Gun-Wook
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.1
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    • pp.32-38
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    • 2008
  • We studied the feeding habits of Sebastes thompsoni based on 421 specimens obtained in monthly collections between January and December 2005 in the coastal waters off Busan, Korea. S. thompsoni was a crustacean feeder, and consumed mainly shrimp and euphausiids. Its diet also included small quantities of amphipods, cephalopods, and fish. It showed distinct ontogenetic changes in feeding habits. Smaller individuals (14-17 cm standard length (SL)), mainly consumed euphausiids. The portion of these prey items decreased with increasing fish size, and larger individuals (>20 cm SL) consumed mainly shrimp such as Leptochela sydniensis.

Feeding Habits of Hexagrammos otakii off the Yoesu Coast of Korea (여수 연안에서 서식하는 쥐노래미(Hexagrammos otakii)의 식성)

  • Jung, Jin Ho;Kim, Heeyong;Moon, Seong Yong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.5
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    • pp.705-713
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    • 2022
  • The feeding habits of Hexagrammos otakii were studied by analyzing the stomach contents of 508 specimens collected from July 2009 to December 2010 off the Yeosu coast of Korea. The total length of the H. otakii specimens ranged from 10.7 to 41.5 cm. H. otakii was found to be a bottom-feeding carnivore that mainly consumed brachyura, amphipoda, but also sonsumed cephalopoda, pisces, anomura, polychaeta, and gastropoda. It was shown through relative importance analysis that the benthic share was 58.1% for brachyura, 24.5% for amphipoda, 7.5% for caridea, and 7.3% for pisces. Brachyura was the main prey item for H. otakii, occupying 35% of the stomach contents. The proportion of brachyura and amphipoda decreased with the growth of H. otakii, and their decrease paralleled the increased consumption of pisces. The shift in feeding habits to larger prey organisms with increasing fish size seems to be one of survival strategies to maximize net energy gain.

Feeding Habits of the Redbanded Searobin Lepidotrigla guentheri in the Coastal Waters off Gori, Korea (고리 주변해역에서 출현하는 꼬마달재 (Lepidotrigla guentheri)의 식성)

  • Baeck, Gun-Wook;Huh, Sung-Hoi;Choi, Hee-Chan;Park, Joo-Myun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.4
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    • pp.372-377
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    • 2011
  • The feeding habits of the redbanded searobin Lepidotrigla guentheri were studied using 186 specimens collected from September to November, 2006, in the coastal waters off Gori, Korea. The sizes of L. guentheri ranged from 7.1 to 16.7 cm total length(TL). L. guentheri is a bottom-feeding carnivore that consumes mainly shrimp, especially Leptochela sydniensis, amphipods, and crabs. Its diet also includes small quantities of stomatopods, mysids, cumaceans, euphausiids, polychaetes, and copepods. Our feeding-strategy graphical method reveled that L. guentheri is a specialized feeder, with a narrow niche width. L. guentheri mainly consumed shrimp of all size classes and did not show significant ontogenetic changes in feeding habits. Smaller individuals(7-11 cm TL) secondly consumed amphipods, with the portion of amphipods in the total diet decreasing as body size increased. Prey size increased significantly as the fish grew in size.

Feeding Habits of Larval Konosirus punctatus from the Nakdong River Estuary, Korea (낙동강 하구역에 출현하는 전어(Konosirus punctatus) 자치어의 식성)

  • Choi, Hee Chan;Han, In Seong;Suh, Young Sang;Huh, Sung Hoi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.5
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    • pp.752-759
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    • 2015
  • We examined the feeding habits of larval Konosirus punctatus using 165 specimens collected from May to August 2011 in the Nakdong River estuary, Korea. We found that larval K. punctatus [3.9-8.4 mm notochord length (NL)] are carnivorous, consuming mainly rotifers. Their diet also included small numbers of rhizopods, tintinnids, euglenoids, copepods, larval bivalves, dinoflagellates, diatoms, and unidentified materials. To evaluate ontogenetic changes in dietary composition, we split the larvae into three size groups: < 5 mm, 5-6 mm, and > 6 mm NL. The smallest size group frequently preyed on rhizopods. As NL increased, the number of rotifers increased relative to those of rhizopods. Larvae also showed bimodal feeding for feeding incidence, with peaks in the midafternoon and at midnight, while the mean number of prey per individual peaked at 18:00-19:00 h.

Influence of care practices on nutritional status of Ghanaian children

  • Nti, Christina Antwiwaa;Lartey, Anna
    • Nutrition Research and Practice
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    • v.2 no.2
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    • pp.93-99
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    • 2008
  • A community-based longitudinal study was conducted in the Manya Krobo District of the Eastern Region of Ghana with the objective of assessing how caregiving practices influence nutritional status of young children in Ghana. The study subjects were one hundred mothers with infants between the ages of 6 and 12 months. Each child was visited at home monthly for a period of six months. On each visit, information was collected on caregiver household and personal hygiene, child's immunization status, child's dietary diversity, caregiver responsiveness during feeding, caregiver hygienic practices related to feeding and child's weight and length. At the end of the study, summary scores were generated for each variable and quality of care practice determined based on their distribution. Classification of child nutritional status was based on z-scores for both weight-for-age and length-for-age. The results revealed that caregivers who exhibited better quality of care practice had well-nourished children. Such caregivers were more likely to practice good household and personal hygiene than those of poorly nourished children (97.1% vs 31.8%, p<0.001). They were also more likely to complete their children's immunization schedules (88.2% vs 62.2%, p<0.001), provide good quality diets from highly diversified sources (79% vs 23%, p<0.001), exhibit high responsiveness during feeding (100% vs 22.7%, p<0.001) and feed under hygienic conditions (100% vs 22.7%, p<0.001). Based on the findings it was concluded that good caregiving practices are associated with improved child nutritional status.

Feeding Habits of Larval Liparis tanakae from the Nakdong River Estuary, Korea (낙동강 하구역에 출현하는 꼼치(Liparis tanakae) 자치어의 식성)

  • Choi, Hee Chan;Huh, Sung Hoi;Park, Joo Myun;Baeck, Gun Wook;Suh, Young Sang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.3
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    • pp.368-376
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    • 2015
  • The Feeding habits of larval Liparis tanakae collected from the Nakdong River estuary were studied. L. tanakae [3.8-10.6 mm notochord length(NL)] was a carnivore thatconsumed mainly copepods. Its diet also included small numbers of free-living flatworms (Macrostomida), tintinnids, cladocerans, and polychaetes larvae. To evaluate ontogenetic changes in dietary composition, three size groups were designated: 3-5, 5-7, and >7 mm. Copepods were the most important prey items for all size groups. The smallest size group frequently preyed on polychaete and bivalve larvae, along with copepods. As notochord length increased, the numbers of cladocerans and Macrostomida increased relative to those of polychaete and bivalve larvae.

Feeding Habits of the Marbled Flounder Pseudopleuronectes yokohamae in the West Sea in Korea (한국 서해에 출현하는 문치가자미(Pseudopleuronectes yokohamae)의 식성)

  • Roh, Tae Hyoung;Choi, Dong Hyuk;Lee, Seung Hwan;Kwon, Dea Hyeon;Han, Kyeong Ho;Kim, Maeng Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.5
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    • pp.583-589
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    • 2022
  • The feeding habits of the marbled flounder Pseudopleuronectes yokohamae were studied using 384 specimens (10.7-52.3 cm in total length) collected from the West Sea, Korea between January and December 2021. P. yokohamae ate mainly polychaeta and gastropoda, incuding teleostei, caridea, euphausiacea, amphipoda and brachyura. The mean number of preys per stomach (mN/ST) showed a statistically significant difference, and the mean weight of prey per stomach (mW/ST) increased as the total length increased. P. yokohamae ate mainly teleostei in spring and winter. P. yokohamae ate mainly euphausiacea in summer and mainly polychaeta in autumn.

Vertical Distribution and Feeding Ecology of the Mirror Dory Zenopsis nebulosa in the Southern Sea of Korea (우리나라 남해안에 서식하는 민달고기(Zenopsis nebulosa)의 수직분포와 식성)

  • Kim, Hye Rim;Kim, Jung Yun;Kim, Hee Yong;Choi, Gwang Ho;Choi, Jung Hwa
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.6
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    • pp.973-976
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    • 2013
  • We observed the vertical distribution and feeding ecology of the Mirror dory, Zenopsis nebulosa, in the Southern Sea of Korea from 2009 to 2013 using an otter trawl. The total length of captured individuals ranged from 11 to 48 cm. Individuals captured at greater depths were significantly larger than those from shallower sites. Fish abundance was significantly related to depth and temperature. We found that 89% of the total catch was obtained at depths between 80 and 140 meters. Prey organisms, including fish, crustaceans, and cephalopods, were found in Z. nebulosa stomachs. Fishes were the main prey items for all size groups. Cephalopods were consumed by individuals > 25 cm in length. Our findings suggested that the vertical distribution of Z. nebulosa varied with depth and temperature, and that the fish are carnivores.

Numerical Flow Analysis for Anti-Vortex Device (AVD) in Oxidizer Tank (산화제 탱크의 와류방지장치 유동해석)

  • Jang, Je-Sun;Han, Sang-Yeop;Kil, Gyoung-Sub;Cho, In-Hyun
    • Aerospace Engineering and Technology
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    • v.9 no.2
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    • pp.168-175
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    • 2010
  • During feeding oxidizer to the engine, vortices are occurred at lower dome of oxidizer tank inside by various working environments and external forces for liquid propellant feeding system of space launch vehicle. To eliminate the vortices or swirls Anti-Vortex Devices(AVD) shall be installed at inside lower oxidizer tank. Using the numerical analysis, we have confirmed the performance of AVD and analyzed the mass flow rate by feeding time and magnitudes of swirls on the free surface of oxidizer or exit surface according to the AVD number and length. Then we could derive the optimal design of the AVD number and length.