• Title/Summary/Keyword: Live prey

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Effect on Enrichment with Schizochytrium sp. and Squid Todarodes pacificus Liver Oil on Fatty Acid Content of Live Feed (오징어(Todarodes pacificus) 간유와 광합성세균을 주원료로 한 동물먹이생물 영양강화제의 지질 영양강화 효과)

  • Park, Jin-Chul;Lee, Bae-Ik;Kwon, O-Nam
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.4
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    • pp.339-344
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    • 2011
  • We investigated the effects of enrichment with oil or bacteria on the fatty acid composition of rotifers and Artemia as live prey. One enrichment(oil source) was mainly composed of squid Todarodes pacificus liver oil; the other(photosynthetic-bacterial source) was primarily made up of Schizochytrium sp. The enrichments were intended to enhance the nutritional value of the live prey, such as their EPA, DHA and n-3 HUFA contents. The lipid content as EPA and DHA of rotifers was higher when enriched with the oil source rather than the photosynthetic-bacterial source. The DHA content of Artemia nauplii after enrichment differed significantly, depending on the type of enrichment used(P<0.05). When the Artemia nauplii were enriched with the oil source, the DHA content was increased to 16.8%, whereas it increased only to 1.1% when enriched with the photosynthetic-bacterial source. These results indicate that selection of the enrichment is important for Artemia nauplii but not for rotifers.

Growth, survival and pigmentation of turbot(Scophthalmus maximus) larvae fed live-prey enrichment

  • Liang Mengqing;Chang Qing;Wang Jialin;Park, Byeong-Dae;Kim, Kwang-Yang
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2003.05a
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    • pp.199-200
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    • 2003
  • After more than 5 years of turbot culture in China, low percent survival and high occurrences of abnormally pigmented juveniles are still major problems for fish farmer. Much research has been directed toward determining the optimal feeding strategies and nutritional requirements for marine flatfish larvae, and considerable advances have been made. The most common live feeds include :Artemia, rotifer and copepods. (omitted)

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Applicability of a Photosynthetic Ciliate, Mesodinium rubrum MR-MAL01 -Usefulness as a Live Prey Species for the Marine Aquaculture of Bivalves- (광합성 섬모류 Mesodinium rubrum MR-MAL01의 응용성(1) 이매패류 종묘생산을 위한 먹이생물 유용성)

  • 김형섭;명금옥;조수근;이원호
    • Journal of Aquaculture
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    • v.17 no.2
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    • pp.115-121
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    • 2004
  • In a series of feeding experiments using the newly established the first laboratory strain of a temperate photosynthetic ciliate, Mesodinium rubrum MR-MAL01, direct evidence was obtained for ingestion of the cultured M. rubrum cells by the bivalves like the Korean scallop, Chlamys farreri and Manila clam. Ruditapes phil-ippinarum. Each experimental Korean scallop and Manila clam removed up to 9,590 and 23,200 cells min-1, respectively. Small particles almost identical to the ruptured cells of MR-MAL01 culture were observed in the gut of the experimental bivalves, although no intact M. rubrum cell was found. In a 28 days rearing experiment, Isoshrysis galbana (KMCC H-2), a microalga, supported better growth of small Manila clam spat (0.46 mm in shell length) than MR-MAL01 strain. For the large Manila clam spat (0.84 mm in shell length), however. MR-MAL01 strain was a better prey item. Mass culture methods for this photosynthetic marine ciliate may be developed for use as live feed in aquaculture of the spat and broodstock of bivalve and small-mouthed fish larvae.

Cannibalism in the Korean Salamander (Hynobius leechii: Hynobiidae, Caudata, Amphibia) Larvae

  • Park, Shi-Ryong;Jeong, Ji-Young;Park, Dae-Sik
    • Animal cells and systems
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    • v.9 no.1
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    • pp.13-18
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    • 2005
  • Cannibalism plays important roles at the levels of both individual and population. To enhance overall rate of successful survival and reproduction, salamander larvae may have evolved to consume both conspecifics and heterospecifics. Consuming conspecifics could result in decreased inclusive fitness possibly by killing relatives. In several salamander species, discrimination of salamander larval siblings from non-siblings and heterospecifics to avoid such a risk has been reported. To determine whether the Korean salamander larvae consume non-siblings more often than siblings and to analyze prey preferences of the salamander larvae in several different experimental conditions, a series of foraging experiments was conducted in the laboratory. We found that 1) large cannibal larvae preyed on small sibling more often than small non-sibling in a mixed group of sibling and non-sibling, 2) cannibal larvae prefered to consume live, weak, and small larvae to dead, healthy, and large larvae, and 3) cannibal larvae consumed heterospecific tadpoles more often than conspecific nonsibling larvae in a mixed group. In addition, the larval density was positively correlated with the occurrence of spacing behavior, one of the agonistic predator behaviors among salamander larvae.

City Beautification and Art: Some Critical Reflections on "Art on the Street" (도시미화와 예술: '길 위의 예술'에 대한 비판적 소고)

  • Lim, Seong-Hoon
    • The Journal of Art Theory & Practice
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    • no.10
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    • pp.47-61
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    • 2010
  • What is Art on the street? Is it a series of artworks or activities performed on the street? In other words, does "art on the street" refer to "Street Art" such as street performance, happening, graffiti, or wall-painting, or does it refer to "Street Furniture" which is related to "City Design" or "Environmental Design"? In a formal sense, they all belong to Art on the street. However, in this paper, I would like to use Art on the street in an even broader sense. To me, " the street" is a metaphor of "environment." Thus Art on the street is the art related to environment; it is an environment art. Art on the street attests the expansion of the concept of art and shows a new possibility of contemporary art. It is a promising new concept of art, but we cannot ignore the misapplication of the concept that we can find at the crossroad of Art on the street and "city beautification." Of course, Art on the street can and sometimes needs to beautify the city. However we still need to ask how to contribute to the city beautification with Art on the street and how to validate such a practice. City space is, most of all, a space that people live in. It sounds a cliche, but it is worth repeating to better understand Art on the street. When we consider the city space in terms of its system or organization, we often overlook that it is the space in which people live, and which people create. Art on the street concerns not the city itself, but the space in which people live and make relations for each other. Without taking this into account, Art on the street becomes a mere means to' embellish' the city and falls prey to the logic of capital. In this paper, I critically reviewed the problems such as City Development, Spectacularization, City Environmental Design, Public Interest and City Museum. I intended to emphasize that Art on the street is produced in the cultural space of city, but it also tends to break the mold of the cultural space and seeks a new possibility. Some might argue that my claims are unrealistic because Art on the street is not an idea but a practice. While humbly accepting the objection, I hope my critical suggestions guide a more productive direction to continue our discussions of Art on the street.

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The Rotifer Brachionus calyciflorus and Water Flea Moina macrocopa as Alternative Foods for Production of the Fighting Fish Betta splendens (베타(Betta splendens)의 부화 후 로티퍼(Brachionus calyciflor)와 물벼룩(Moina macrocopa)의 섭취, 소화속도 및 성장)

  • Kwon, O-Nam;Park, Kie Young;Park, Heum-Gi
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.4
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    • pp.393-398
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    • 2013
  • The purpose of this study was to determine how an ornamental fish, such as the fighting fish, Betta splendens would respond to the use of freshwater live-prey, such as rotifers Brachionus calyciflorus and water fleas Moina macrocopa. Ingested quantity, digestive velocity and somatic growth were compared between larvae fed a freshwater rotifer and those fed boiled yolk. Food efficiency and somatic growth were compared between larvae that were fed freshwater water fleas and those fed a micro-diet developed for flounder ($250{\mu}m$, I-hwa Ltd.). The number of rotifers ingested by larvae reached a maximum of 191 per day. However, based on the number ingested per hour and the digestive velocity of consumed rotifers, the maximum ingestible and digestible number of rotifers was calculated to be 272 per day. A maximum of 67 individuals (mean, 49.8 individuals) could be completely digested within the 1-h period from 90 to 180 min after feeding. Somatic growth was enhanced in larvae that were fed rotifers compared to those fed boiled yolk. Larvae exhibited greater growth at rotifer densities of 30 and 40 per mL than at lower densities. Among the water-flea (M. macrocopa and Bosmina sp.) and micro-particle diets, feeding with M. macrocopa resulted in the greatest somatic growth of larvae during the water-flea feeding stage.

Diel Changes in the Diet of Rudarius ercodes: A Diurnal Omnivore and Nocturnal Carnivore (그물코쥐치의 먹이습성의 일별 변화: 낮은 잡식성, 밤은 육식성)

  • Kwak, Seok Nam;Huh, Sung-Hoi;Choi, Chang Geun
    • Korean Journal of Ichthyology
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    • v.18 no.3
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    • pp.178-183
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    • 2006
  • Diel changes in the feeding habits of Rudarius ercodes were investigated in an eelgrass bed of Jindong Bay, Korea. The main food components for R. ercodes (1.6~ 4.3 cm SL) were gammarid amphipods, eelgrass, polychaetes and urochordates. Most dietary items were inhabitants of an eelgrass bed. Diel variations in diet and feeding activity occurred. The diet of R. ercodes underwent changes from eelgrass and gammarid amphipods (omnivore) at day to mainly gammarid amphipods, polychaetes, and urochordates (carnivore) at night. Rudarius ercodes probably took detached eelgrass leaves and grazed live eelgrass during day, whereas feeding on gammarid amphipods, polychaetes, urochordates, and bivalves were facilitated by nocturnal movement and activity of these prey during night. The feeding activity of R. ercodes was also correlated with periods of high tides.

Studies on the Feeding Habits of Korean aucha perch, Coreoperca herzi in the Geum River, Korea (금강에 서식하는 꺽지(Coreoperca herzi)의 식성)

  • Byeon, Hwa-Keun
    • Korean Journal of Environment and Ecology
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    • v.31 no.5
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    • pp.472-478
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    • 2017
  • The feeding habits of Coreoperca herzi were investigated from specimens collected in the Geum River, from March to December 2016. The specimens were separated into groups of 38~70 mm, 71~109 mm, and over 110 mm in total length. The live foods of C. herzi included Ephemeroptera, Odonata, Plecoptera, Coleoptera, Diptera, Trichoptera, and fishes. The Korean aucha perches fed mostly on aquatic insects which took up 98.8% of food regarding the number, 55.8% regarding the biomass, and 97.1% in terms of iregarding the index of relative importance. They were carnivorous in diet and predators (stalker) in food intake characteristics and forms when applying Keenleyside's classification. The main food sources of C. herzi were Ephemeroptera, Diptera, and Trichoptera while Odonata, Plecoptera, Coleoptera, and fishes were rare. A food migration was observed since less Ephemeroptera was found and more Trichoptera and fishes were found in the biomass of the feed consumed by larger species. The amount of Coleoptera and Diptera did not change much with the size of the species. The overall composition of live food was not seasonal. The result of the study indicates that, when restoring the streams to be the habitat for the natural population increase of Coreoperca herzi, the environment should be inhabitable to Ephemeroptera, Diptera, and Trichoptera which are the main foods.

Mass culture of the brackish water cyclopoid copepod Paracyclopina nana Smirnov (기수산 요각류 Paracyclopina nana의 대량배양)

  • Lee, Kyun-Woo;Choi, Young-Ung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.8
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    • pp.262-266
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    • 2016
  • Marine copepods are ideal live prey for fish larvae, and many studies on the mass culture of the organism have been reported. This study performed a mass culture of the brackish copepod Paracyclopina nana containing nauplius and C4-adult production methods. In nauplius production, the harvested nauplii over 95% were comprised of N1 and N2. Daily mean nauplius production of two trials for 15 days were $6.9{\times}10^6$ and $7.2{\times}10^6$ individuals, respectively. The densities of the adult females were maintained at a similar level of the initiation during production. In C4-adult production, the proportion of harvested copepods containing C4-adult males, females and ovigerus females were 49%, 28%, and 18%, respectively. The daily mean nauplius production of the two trials for 16 days were $8.2{\times}10^5$ and $9.0{\times}10^5$ individuals, respectively. As a result, the continuous production of P. nana using the mass production system was successful. Therefore, the continuous and stable feeding for fish larvae in aquaculture would be possible by the selection of the copepod culture method depending on the mouth size of the fish.

Shadows and Evil in Inferno of Divine Comedy (신곡의 지옥편에 나타난 그림자와 악)

  • Dukkyu Kim
    • Sim-seong Yeon-gu
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    • v.37 no.2
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    • pp.49-76
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    • 2022
  • This study is to illuminate the problem of shadows and evil appearing in contemporary events in the midst of a period of upheaval through Inferno of Divine Comedy. First, the concept of shadow and evil were briefly summarized in analytical psychology and discussed the importance of considering the concepts with the empirical aspect of relativity and ethics in the field of psychotherapy. The 14th century, the age of Dante, was the embryonic period of the Renaissance beyond the end of the Middle Ages. It was when Dante, who was writing Divine Comedy, had to take off his persona forcibly and live in exile. In a nutshell, it was a transition period for both the individual and the collective. The dark forest is a nigredo, darkness and chaos we face in this transition, but it can be a place of transformation and rebirth. The three beasts (leopard, lion, and she-wolf) encountered in the forest can be considered as the instinctual images that Dante ignored and alienated, which the medieval Christian world had suppressed and eliminated. Especially at the collective level, as destructive instincts, ferocious beasts roam throughout society when a crisis breaks dominant laws of values. The three beasts of Inferno appear as phenomena of shadows and evil. The aspect of leopard was explored Cerberus and Chiaco(pig) as a symbol of greed, and the lion, Farinata as the form of violent passion. The aspect of the she-wolf was examined as Geryon, a deceitful monster with a beast nature hidden behind goodness, the giants in the frozen lake of Cocytus, and Branca D'Oria, who betrayed and murdered the country and family. Inferno reveals the "state" of being trapped when one yields to the evil hidden within oneself and falls into prey.