• 한국수산과학회지
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• 제41권4호
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• pp.282-288
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• 2008

Feeding ecology of the white-spotted conger eel Conger myriaster in the Southern Sea of Korea was examined. Specimens were caught monthly from January 2004 to December 2006. Primary prey items of C. myriaster included fish, shrimp, and crabs. C. myriaster exhibited a nocturnal feeding strategy and preyed upon a wide range of pelagic fish groups(e.g., Engraulis japonicus, Glossanodon semifasciatus, and Maurolicus muelleri). This species was also an opportunistic feeder that exploited the available prey in each area(i.e., fish in the A area and shrimp in the B area). The composition of the diet of C. myriaster exhibited seasonal fluctuations that were related to food availability during each season. The observed ontogenetic shifts in diet were relatively clear, despite substantial overlap between the 10 cm and 20 cm groups of C. myriaster.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.76-77
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• 2003

Olive flounder Paralichthys olivaceus larvae and early juveniles were reared for 43 days after hatching in order to observe the effects of starvation during development and metamorphosis. Morphological, histological and biochemical measurements were made to assess the nutritional condition during growth and starvation from pre-matamorphic through post-metamorphic phases. Two groups of fish were compared ; one with sufficient food supply and one under continuous starvation until death. Among morphometric analyses, both ratios of body height at anus/head height and pre-/post-anal lengths appeared to be sensitive to starvation during which substantial reduction was observed within a day of food deprivation. Histological variables as intestinal and rectal epithelial heights and gall bladder volume changed significantly with onset of starvation. The gut epithelial heights of starving fish decreased with advances in starvation, although they fluctuated during mid-metamorphic phase. In contrast, gall bladder volume increased remarkably soon after starvation. Ontogenetic changes in both gut epithelial height and gall bladder volume were evident, those associated with settlement and/or completion of metamorphosis. Abrupt decrease in the RNA/DNA ratios of starving fish were found right after onset of starvation. Even in the fed fish marked fluctuations in its ratios during metamorphosis were observed, evident by decreasing from late-metamorphic to post-metamorphic stages. These findings suggest that a combination of morphologically and histologically sensitive characteristics, and biochemical measurement could be utilized as a measure to evaluate nutritional condition related to starvation in wild olive flounder larvae and juveniles.

• Animal cells and systems
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• 제15권4호
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• pp.325-336
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• 2011

Feeding ecology was compared among the three tonguefishes Cynoglossus abbreviatus, C. joyneri and C. robustus, collected from Seto Inland Sea, Japan, from June 2000 to May 2001. They are benthivores, consuming mainly gammarid amphipods, shrimps, crabs, gastropods, bivalves and ophiuroids. C. abbreviatus consumed greater proportions of ophiuroids whereas C. joyneri and C. robustus ate more amphipods and shrimps. While C. abbreviatus consumed mostly ophiuroids in all size classes, the diets of C. joyneri and C. robustus showed ontogenetic changes in feeding habits; smaller individuals of C. joyneri and C. robustus consumed gammarid amphipods, whereas larger C. joyneri ate shrimps and gastropods, and larger C. robustus fed mainly on gastropods, crabs, bivalves and polychaetes. Cluster analysis based on diet similarities emphasized that the three Cynoglossus species could be categorized on a size-related basis into three feeding groups: smaller C. joyneri and C. rubustus (<25 cm TL) could be classified as group A, and the larger of them (>25 cm TL) as group B, whereas C. abbreviatus was categorized as group C. This means that some degree of resource partitioning can occur among the three Cynoglossus species. The seasonal changes in the diets were also significant for the three Cynoglossus species.

• Fisheries and Aquatic Sciences
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• 제18권3호
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• pp.301-309
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• 2015

Chub mackerel, Scomber japonicus, larvae and juveniles were reared from hatching to 35 days after hatching (DAH), and the development of their digestive systems was histologically investigated. The larvae were initially fed on rotifers and Artemia nauplii starting around 19 DAH, and thereafter on Artemia nauplii, fish eggs, and a formulated feed mixture. The primitive digestive system differentiated at 3 DAH; the digestive tract was distinctively divided into the buccopharyngeal cavity, esophagus, stomach, air bladder, intestines, and rectum. The gastric gland and pyloric caeca first appeared at 5 and 7 DAH, respectively. The stomach was divided into cardiac, fundic, and pyloric regions in the preflexion phase. The number of gastric glands and pyloric caeca, as well as the volume of the gastric blind sac increased markedly, with development continuing into the juvenile stage. The precocious development of the digestive system during the larval period might be related to the early appearance of piscivory, which is able to support high growth potential. The organogenesis results obtained for this precocial species represent a useful tool to aid our understanding of the physiological requirements of larvae and juveniles to ensure optimal welfare and growth under aquaculture conditions, which will improve current rearing practices of this scombrid species.

• 한국수산과학회지
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• 제44권4호
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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.

• 한국어류학회지
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• 제9권2호
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• pp.221-227
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• 1997

1994년 1월부터 1994년 12월까지 광양만 대도주변 잘피밭에서 채집된 주둥치의 식성을 조사하였다. 주둥치는 주로 요각류와 게의 유생을 먹었으며, 그 외 갯지렁이류, 단각류, 곤쟁이류, 새우류 등을 소량씩 먹었다 주둥치가 성장함에 따라 먹이생물의 조성 및 크기가 점차 변하였다. 체장이 작은 크기에서는 요각류를 상당히 많이 먹었으나, 체장이 증가하면서 위내용물 중 요각류가 차지하는 비율이 점차 낮아진 반면, 갯지렁이류의 비율은 점차 증가하였다. 한편, 게의 유생은 전 크기군에 걸쳐 지속적으로 많이 섭이되었다. 대체적으로 계절에 관계없이 게 유생의 섭이 비율은 거의 일정하였으나, 요각류와 갯지렁이류의 비율은 뚜렷한 계절 변동을 보였는데, 이는 출현하는 주둥치의 크기 조성이 계절에 따라 달라졌기 때문이다.

• 수산해양기술연구
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• 제53권1호
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• pp.107-113
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• 2017

The feeding habits of larval (5.0~27.0 mm SL) Clupea pallasii were examined and 1,523 individuals were collected from November 2010 to March 2011 in the coastal water of Eastern Jinhae Bay, Korea. Larval C. pallasii were fed mainly on copepods that constituted 55.2% in IRI. Monogeneans were the second largest prey component, another prey items tintinnids, cladocerans and ostracoda. The results of analysis in ontogenetic changes exhibit high during the daytime, two small size classes (${\leq}10mm$, 10~15 mm) mainly fed copepods. while the percentage of coperpods decreased, monogeneans ratio increased in 15~20 mm size class. Feeding rate in diel difference of larval C. pallasii were high during the daytime.

• 한국수산과학회지
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• 제45권1호
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• pp.76-81
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• 2012

The feeding habits of daggertooth pike conger Muraenesox cinereus were studied using 380 specimens collected in the coastal waters off Goseong, Korea, from June to September, 2011. The M. cinereus ranged from 10.0-23.7 cm in anal length (AL). M. cinereus is a piscivore that consumes mainly fish. Engraulis japonicus was the preferred prey, but its diet also included small numbers of crabs, shrimps, cephalopods, and bivalves. The feeding strategy graphical method revealed that M. cinereus is a specialized feeder with a narrow niche width. All size classes of M. cinereus consumed fish and M. cinereus did not show significant ontogenetic changes in feeding habits. The diet overlap index between size classes was >0.96, indicating high diet similarities. The prey size increased significantly with M. cinereus size.

• 한국수산과학회지
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• 제50권5호
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• pp.616-620
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• 2017

The feeding habits of post-larval Yatabe blenny Parablennius yatabei (2.0-9.8 mm SL) were examined on the basis of 158 individuals collected from June to October in the coastal waters of eastern Jinhae Bay, South Korea. Based on the index of relative importance (IRI), post-larval P. yatabei fed 94.4% on copepods and 5.6% on tintinnids. The preference of post-larval P. yatabei for copepods to other prey items results from ontogenetic changes. The dietary percentage of copepods increased as fish size increased and tintinnids became less important. The feeding rate of post-larval P. yatabei was consistent at all times of day.

• 한국어류학회지
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• 제13권4호
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• pp.230-236
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• 2001

강원도 홍천군 서면 반곡리에서 2000년 1월부터 12월까지 Gobiobotia brevibarva를 대상으로 식성을 조사 연구하였다. G. brevibarba의 주요 먹이 생물은 Ephemeroptera, Trichoptera 그리고 Diptera였으며 그 밖에 Plecoptera와 Coleoptera 등이 검출되었다. 성장함에 따라 먹이 조성에 있어 변화를 보이는데 작은 체장 (21~50 mm)에서는 Diptera, Ephemeroptera를 주로 먹었으나 성장하면서 다양한 먹이와 비교적 크기가 큰 Trichoptera로 먹이 전환이 일어났다. Ephemeroptera는 봄 과 여름 그리고 가을에 양의 선택성을 겨울에는 음의 선택성을 나타낸 반면 Diptera는 3월과 10월 그리고 11월에 양의 선택성을 나타내었다.