• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.4
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• pp.352-358
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• 2011

The presence of ISKNV-like viruses in various freshwater ornamental fish species imported from Asia was confirmed by polymerase chain reaction(PCR) amplification of the ATPase(adenosine triphosphatase) gene. Interestingly, molecular analyses of the Open Reading Frame 25(ORF25) region of these isolates based on the ISKNV(Infectious spleen and kidney necrosis virus) genome revealed the presence of various repetitive sequences. ORF25 repeat sequence length had no effect on cumulative mortality of rock bream Oplegnathus fasciatus challenged with tissue homogenates of infected pearl gourami, Trichogaster leeri; silver gourami, Trichogaster microlepis; blue gourami, or Trichogaster trichopterus. All isolates induce cumulative mortalities after 12 days of infection, confirming that ORF25 polymorphism did not affect the pathogenicity of ornamental fish megalocytiviruses that cross infect rock bream, a seawater fish. Also, no statistically significant differences in spleen index or viral copy number in infected tissues was detected between isolates with varying ORF25 repeat sequence lengths. However, further studies are necessary to fully characterize the functional characteristics of these polymorphisms in megalocytivirus disease in ornamental fishes.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.4
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• pp.302-312
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• 2010

In order to describe the performance of a wedge type jellyfish excluder device, a series of fishing experiments was carried out in the coastal areas of Yokji Island, southern Korea in 2009, using a trawl net with a cover net. The body size and weight of each individual (fish or jellyfish) caught in the experimental fishing were measured. In the case of giant jellyfish the bell diameter and weight were measured. The catch species was composed of giant jellyfish (Nemopilema nomurai), silver croaker (Pennahia argentata), yellow croaker (Larimichthys polyactics), finespotted flounder (Pleuronichthys cornutus), largehead hairtail (Trichiuruslepturus), melon seed (Psenopsisanomala) and so on. The weight ratio and individual ratio of total fish escaped through the outlet of the excluder device were 0.322 and 0.320, respectively. The weight ratios of giant jellyfish excluded from the trawl net ranged from 0.740 to 0.921 (average 0.852/haul). It means that the wedge type jellyfish excluder device performed well and allowed the most of the giant jellyfish to exclude through the trawl net. The approximately 70% of fish entered in trawl net was caught. The wedge type excluder device needs some improvements to minimize the fish escape from the trawl nets in the future.

• Journal of Environmental Health Sciences
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• v.39 no.4
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• pp.369-375
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• 2013

Objectives: This study was conducted to identify factors determining the toxicity of manufactured silver nano-particles (AgNPs) on aquatic organisms. Methods: For this purpose, we prepared several AgNPs with varied characteristics, including hydrodynamic size (nano-$^{ABC}Ag^{Cit}\;vs$-sized-$^{ABC}Ag^{Cit}$), impurities ($^{ABC}Ag$ stock vs $^{ABC}Ag$), and citrate capping ($^{ABC}Ag^{Cit}$), using a commercially available manufactured AgNP ($^{ABC}Ag$ stock). Acute tests were conducted using larval zebrafish (Danio rerioI). In addition, in order to determine the ecotoxicological potentials of various capping agents, toxicity tests were conducted with microbes, waterfleas, and fish for eight different capping agents that are used for NPs. Results: The toxicity of AgNPs in terms of 96 h fish $LC_{50}$ increased in the following order: $^{ABC}Ag$ stock < $^{ABC}Ag=^{ABC}Ag^{Cit}=nano-^{ABC}Ag^{Cit}$ < ${\mu}$-sized-$^{ABC}Ag^{Cit}$ < $AgNO_3$. After removing impurities by dialysis, 96 h $LC_{50}$ value decreased significantly from $126.6{\mu}g/L$ (95% confidence intervals [CI]: 107.0-146.2) ($^{ABC}Ag$ stock) to $78.6{\mu}g/L$ (CI: 72.7-84.8) ($^{ABC}Ag$). For ${\mu}$-sized-$^{ABC}Ag^{Cit}$ (ranging between 3.9 and 40.6 nm) and $^{ABC}Ag^{Cit}$ (40.6 nm and $9.1{\mu}m$), the 96 h $LC_{50}$ of the former ($43.9{\mu}g/L$, CI: 36.0-51.7) was approximately two-fold lower than that of the latter ($87.0{\mu}g/L$, CI: 73.5-100.3). Conclusions: In this study, we found that for acute lethality, the contribution of impurities and particle size was significant, but that of citrate was negligible.

• Journal of Veterinary Clinics
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• v.31 no.6
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• pp.502-506
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• 2014

Recently nano particles have proven for wide array of bioactive properties. In the present study, antibacterial properties of chitosan silver nano composites (CAgNCs) were investigated against fish pathogenic Edwardsiella tarda. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of CAgNCs against E. tarda were $25{\mu}g/mL$ and $125{\mu}g/mL$, respectively. The field emission scanning electron microscope (FE-SEM) image of CAgNCs treated E. tarda showed the strongly damaged bacteria cells than non-treated bacteria. Furthermore, treatment of CAgNCs induced the level of intracellular reactive oxygen species (ROS) in E. tarda cells in concentration and time dependent manner suggesting that it may generate oxidative stress leading to bacterial cell death. In addition, MTT assay results showed that the lowest cell viability at $100{\mu}g/mL$ of CAgNCs treated E. tarda. Overall results of this study suggest that CAgNCs is a potential antibacterial agent to control pathogenic bacteria.

• Development and Reproduction
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• v.19 no.1
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• pp.25-31
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• 2015

We have launched an investigation for Embryonic Development, Larvae and Juvenile Morphology, of Buenos aires tetra in order to build basic data of Characidae and fish seeding production. We brought 50 couples of Characidae from Bizidduck aquarium in Yeosu-si, Jeollanamdo, from Korea on March of 2015. We put them in the tetragonal glass aquarium ($50{\times}50{\times}30cm$). Breeding water temperature was $27.5{\sim}28.5^{\circ}C$ (mean $28.0{\pm}0.05^{\circ}C$) and being maintained. The shape of fertilized egg was round shape, and it was adhesive demersal egg. The egg size was 0.63~0.91 mm (mean $0.74{\pm}0.07mm$, n=20). After getting fertilized egg, the developmental stage was gastrula stage, and embryo covered almost two-thirds of Yolk. Incubation was happened after 16 hours 13 minutes from gastrula stage, and the tail of juvenile came out first with tearing egg capsule. Immediately after the incubation, prelarvae had 3.78~3.88 mm length (mean $3.84{\pm}0.04mm$, n=5), and it had no mouth and anus yet. 34 days after hatching from the incubation, juvenile had 8.63~13.1 mm (mean $10.9{\pm}1.66mm$), and it had similar silver-colored body shape with its mother.

• Journal of the Korean Society of Food Culture
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• v.18 no.6
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• pp.491-505
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• 2003

Yeolgujatang is traditional casserole with meat, fish and vegetables in special pot. Name of Yeolgujatang was in 1800s, as yeolgujatang, yeolgujatangbang, yeolguja, in 1900s, Yeolgujatang, royal feast food in Yi Dynasty was yeolgujatang, Meon-sinseolro, tangsinseolro. Yeolgujatang frame has legs and a lid, and a cylinder that can contain charcoal at the center of its rounded pot. with this charcoal, food can be cooked. Its material has changed from brazier to brassware, stainless steel, and silver. Nowdays electric sinseolro was also launched, which uses electric power instead of charcoal. Materials in yeolgujatang are beef, intestines, pork, chicken, pheasant, fish, sea bream, abalone, shrimps, vegetables, mushroom, ddock, guksu, cooked rice, seasening and garnish. Nutrition of Yeolgujatang per capita contains 221.5kal of calory, 17.3g of protein, 16.5g of fat, 6.1g of carbobydrates, 2g of fiber, 57.6mg of calcium, 208mg of phosphorus, 4.3mg of ferrum, $2177{\mu}gRE$ of vitaminA, 1.58mg of vitamin $B_1$, 0.3mg vitamin $B_2$, 6.6mg of vitaminC and 5.26mgNE of niacin. Yeolgujatang is excellent in nutrition, except for calcium and vitaminC.

• Journal of Veterinary Clinics
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• v.24 no.1
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• pp.56-58
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• 2007

This study was attempted to find appropriate surgery for gill cover curling disorder in arowana. Gill cover curling is a usual clinical findings in arowana, which often lead to death of the fish by dyspnea. Two different surgical methods were implemented in this study for gill cover by using cutting and incising fm-like fer two silver arowana. The surgery was identified to be successful since the fish healthily recovered. This experiment demonstrated that gill cover curling can be cured by using surgery.

• Animal cells and systems
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• v.13 no.3
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• pp.323-329
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• 2009

We analyzed partial sequences of cytochrome b (cyt-b), a mitochondrial DNA (mtDNA) gene, to determine the genetic relationships between six horsehead fish species: Branchiostegus japonicus, Branchiostegus albus, Branchiostegus auratus, Branchiostegus argentatus, Branchiostegus wardi, and an unidentified Branchiostegus species. The specimens were collected in Korea, China, Japan, and Vietnam. We compared their molecular phylogenetic relationships inferred from mtDNA cyt-b sequences with an osteological analysis. The unidentified species, B. sp., was similar to B. albus in terms of the lack of triangular silver-white dot at the posterior region of eyes (vs. large one present in B. japonicus), but was also similar to B. japonicus in terms of the presence of a straight-shaped first hemal spine (vs. a curve-shaped hemal spine in B. albus). Analysis of the mtDNA cyt-b sequences indicated that the smallest estimated sequence divergence was between the B. japonicus and B. sp. (0.70-0.94%), whereas the largest difference was between B. auratus and B. argentatus (23.06-23.36%). Both the maximum parsimony and maximum likelihood trees showed that the B. sp. was closely clustered with B. japonicus, and that B. auratus was most distant from the other species. When comparing the osteological characters, UPGMA tree showed that the B. japonicus and B. sp. were the most closely clustered species, and B. auratus was the most distantly clustered fish relative to the other species. The shape of the nasal, otolith and first hemal spine was informative for distinguishing B. auratus from the other species. These osteological differences were consistent with the differences in mtDNA.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1457-1464
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• 2008

For the effective use of under-utilized resources, silver-stripe round herring (SSRH), the plain-dried SSRH was investigated and compared with boiled-dried SSRH and boiled-dried anchovy on the food component and sensual characterization. Moisture content and salinity of the plain-dried SSRH were 31.9% and 7.6%, respectively. Moisture content of the plain-dried SSRH was higher, while the salinity was lower than those of boiled-dried SSRH and anchovy. According to the results of peroxide value, fatty acid composition, Hunter b value, and browning index, the rancidity was higher in plain-dried SSRH than in boiled-dried SSRH and anchovy. When compared to the boiled-dried SSRH and anchovy, the plain-dried SSRH was higher in calcium and phosphorus contents, while lower in total content of amino acid. According to the results of hot-water soluble-N, trichloroacetic acid-N, free amino acid, and taste value, the taste of plain-dried SSRH was superior to those of the boiled-dried SSRH and anchovy. The results of chemical components and sensory evaluation indicated that the plained-dried SSRH could be substituted for boiled-dried anchovy classified into special grade, if fish odor of SSRH can be improved.

• Journal of the Korean Applied Science and Technology
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• v.10 no.1
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• pp.1-8
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• 1993

The possibilities for HPLC analysis of lipids have been revolutionised by the availability of evaporative light-scattering detectors, with which the response is independent of the nature of the mobile phase and does not depend On the presence of specific chromophores in the lipids. It was thus possible to develop an HPLC procedure, involving ternary gradient elution, for separating all the lipid classes in animal tissues in a single step. Although reversed-phase HPLC has been widely used for the analysis of molecular species of lipids, sliver ion chromatography can be a valuable alternative. For example, a stable silver ion column for HPLC was developed which permitted resolution of molecular species of triacylglycerols, even from such complex samples as fish oils, again With light-scattering detection and gradient elution. The capacity for HPLC resolution of diastereomeric diacyl-sn-glycerol derivatives, prepared from triacylglycerols. has lead to a new simple method for stereospecific analysis of the latter.