• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1445-1451
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• 2007

A sensitive optical waveguide lightmode spectroscopy-based immunosensor was developed to detect vitellogenin in seawater flatfish (Paralichthys olivaceus). For this purpose, anion-exchange column chromatography with DE-52 resin was used to purify flatfish vitellogenin from flatfish serum containing vitellogenin that had been induced using an intraperitoneal $17{\beta}$-estradiol injection. The anti-flatfish vitellogenin antibody used as the biological component of the above immunosensor was prepared using the purified flatfish vitellogenin. The change in the incoupling angle according to the complexation between the flatfish vitellogenin and its antibody, immobilized over an optical grating coupler sensor chip, was measured to calculate the sensor response. The immunosensor was quite specific to flatfish vitellogenin binding, based on no sensor response in the case of bovine serum albumin immobilization. When plotted using double-logarithmic scales, the sensor responses increased linearly in flatfish vitellogenin concentrations of 0.00675-67.5 nM, with a detection limit of 0.0675 nM. The reusability during seven repetitive measurements was reasonably fair for the preliminary screening of flatfish vitellogenin.

• 한국어병학회지
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• 제22권3호
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• pp.219-228
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• 2009

The genomic and subgenomic RNAs of fish nodavirus encode the four proteins, protein A, capsid protein, non-structural protein B1 and B2. In this study, we describe the immune response of olive flounder Paralichthys olivaceus immunized with live fish nodavirus or recombinant capsid protein, non-structural protein B1 and B2 expressed in E. coli. Nodavirus-infected flounder produced antibodies to capsid protein, B1 and B2 and nodavirus-neutralizing activities were detected in the serum of the nodavirus-infected flounder. The flounder were immunized against the three recombinant proteins of fish nodavirus and the sera from these immunized fishes were assayed for nodavirus-specific antibody by ELISA and a neutralization test. In the immunized flounder, all three recombinant proteins induced the production of similar levels of antibody, but only the antibody to capsid protein significantly neutralized nodavirus. These results indicate that all three nodaviral proteins are immunogenic in flounder, but only the capsid protein can induce neutralizing antibody against nodavirus.

• 한국어병학회지
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• 제22권3호
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• pp.383-389
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• 2009

Analysis of expressed sequence tags (ESTs) is an efficient approach for gene discovery, expression profiling, and development of resources useful for functional genomics studies. As part of studies on the immune system of olive flounder, a total of 251 EST sequences from gill cDNA library were generated to identify and characterize important genes in the immune machanisms of olive flounder. Of the 251 clones, 126 clones (50.2%) were identified as orthologues of known genes from olive flounder and other organisms. Among the 126 EST clones, 16 clones (12.7%) were representing 9 unique genes identified as homologous to the previously reported olive flounder ESTs, 100 clones (79.4%) representing 103unique genes were identified as orthologs of known genes from other organisms. We also identified several kinds of immune associated proteins, indicating EST as a powerful method for identifying immune related genes of fish as well as identifying novel genes. Further studies using cDNA microarrays are needed to identify the differentially expressed transcripts after disease infection.

• 한국어병학회지
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• 제21권3호
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• pp.209-217
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• 2008

A disease with mass mortality characterized exophthalmia and abdominal distension by ascites occurred in farmed starry flounder, Platichthys stellatus in Pohang since October of 2007. Severe necrosis and infiltration of inflammatory cells were observed in tissue histopathological sections from liver, kidney, spleen and heart of the diseased fish. The catalase-negative and gram positive cocci with -hemolysis were isolated from moribund fish. Analysis of the API profiles and the multiplex PCR of the isolates showed that strains were identified as Streptococcus parauberis. In API profiles, S. parauberis isolated from starry flounder differed from those of olive flounder, Paralichthys olivaceus to the test of arginine dihydrolase, D-mannitol, D-sorbitol and α-lactose. And the strains, PH0710 and PH0711, were strongly lethal for starry flounder (LD50 ranging from 4.2×103~4.2×102 cfu/fish at 7 days after intraperitoneally inoculation). This is the first report on a S. parauberis infection in starry flounder.

• 한국수산과학회지
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• 제35권5호
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• pp.542-544
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• 2002

This study was carried out to evaluate the ciliates Euplotes sp. as a live food for marine fish larvae. The ciliates and the rotifers Brachionus plicatilis, which were cultured with the baker's yeast Saccharomyces cerevisiae and the $\omega$-yeast emulsified with cuttle fish liver oil, were supplied to the larvae of flounder Paralichthys olivaceus and grouper Epinephelus akaara. Considering the size difference between the ciliates 68 $\cdot$ 7 $\mu$n and the rotifers 160 $\cdot$ 20 $\mu$n, the rotifers and ciliates were supplied to the larvae tank with the density of 2 inds./mL and 20 inds./mL, respectively. The survival rate and growth in length of the flounder larvae fed on rotifer were significantly higher than those on Euplotes sp.. In grouper larvae which have a small mouth diameter, even the survival rate of the larvae fed on the ciliates was better than that on the rotifers, it was very low less than $20\%$. Therefore, Euplotes sp. seem to be incongruent as a live food for marine fish larvae.

• 한국양식학회지
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• 제13권1호
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• pp.21-27
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• 2000

The successful gene transfer and transient expression was demonstrated in olive flounder embryos using lipofected sperm. Olive flounder sperm interacted with foregn plasmid DNA encapsidated by positively charged liposome. The maximum plasmid copy number that associated with the sperm was 5 copies/sperm based on the examination of DNA blot assay. The foreign DNA was transferred into fertilized eggs without any adverse effect on fertilization and survival of embryos (P>0.05) and retained in embryos until at least 42 hours with successful expression. The maximal expression was detected in 18 hours after fertilization at 18$^{\cird}C$ and gradually decreased with development of embryo. Most of DNA transferred into embryos persisted extrachromosomally without significant sign of integration or replication.

• 대한수의학회지
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• 제37권1호
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• pp.203-212
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• 1997

Antibacterial efficacy and safety of copper sulfate pentahydrate (5% solution) was evaluated in laboratory and field studies for disinfection of some fish bacterial pathogens in cultured fish, flounder(Paralichthys olivaceus), mirror carp(Cyprinus carpio), gold fish(Carrassius auratus) and eel(Anguilla japonica). Dipping of fishes for acute toxicity was performed for a period of 48h, and the TLm value(median tolerance limit) were 4.0ppm in mirror carp and flounder, 4.4ppm in rainbow trout, and 10.0ppm in gold fish. After exposure below than TLm value for 1 month, no side effects and histopathological changes were observed. The test drug were shown high antibacterial activities against most bacterial pathogens by exposure in the laboratory and field trials. However, Aeromonas salmonicida showed a resistance to the dosage. We can prevent outbreaks of bacterial diseases of fish by the dosage of 1ppm for 6hr and the test drug is thought to be used effectively and widely as a disinfectant against most bacterial fish pathogens.

• Fisheries and Aquatic Sciences
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• 제15권3호
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• pp.233-239
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• 2012

Hematological analysis can provide crucial information for monitoring the health of fish. However, there is no current information available regarding hematological changes in olive flounder following infection by Vibrio scophthalmi. In this study, hematological and biochemical alterations were determined in olive flounder infected by the high virulence strain (HVS) and low virulence strain (LVS) of V. scophthalmi. Survival in serum, skin mucus, and macrophages of olive flounder was also compared between the HVS and LVS. The results demonstrated that the hematocrit value in infected fish declined from 23.4% at 0 h to 18.0% at 168 h post infection. The total protein concentration in fish infected with the HVS was significantly higher than in fish infected with the LVS and a non-infected control. Lysozyme activity was significantly different between infected and control fish. The HVS survived in serum and cell numbers increased substantially, while cell numbers of the LVS in serum decreased. These changes in hematological characteristics in fish infected by V. scophthalmi can be used as an effective and sensitive index to monitor the physiological and pathological conditions of fish. The survival and reproduction of V. scophthalmi in host serum, skin mucus, and macrophages play a major role in systemic infection and can serve as a virulence indicator for different strains.

• 한국수산과학회지
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• 제44권2호
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• pp.173-178
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• 2011

The species and size compositions of fishes in the coastal waters off Taean were determined using samples collected with a two-sided fyke net in 2008. A total of 22 species, 2,371 individuals and 1,351 kg of fish were collected during the study. Of the fish collected, semi-benthic fishes such as Sebastes schlegelii, Mugil cephalus and Chelon haematocheilus were the most abundant (77.5% and 76.4% for total number of individuals and biomass, respectively). Benthic fishes such as Pleuronectus yokohamae and Paralichthys olivaceus were collected in almost all seasons but were low in abundance (5.3% and 4.1% for total number of individuals and biomass, respectively). Seasonal migrants were plentiful; specifically, Seriola quinqueradiata was abundant in November while Konosirus punctaus was common in July. Seasonal migrants of small-sized fish have been known to be abundant in the coastal water of western Korea including the study area, but few fish less than 100 mm were collected due to the large mesh size (30 mm) of the net used.

• 한국어병학회지
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• 제13권2호
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• pp.143-146
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• 2000

본 연구에서는 bronopol과 bithionol을 이용하여 양식 넙치에 기생하는 Ichthyobodo sp.의 치료효과를 조사하였으며, 그 효과를 formalin과 비교하였다. formalin 200 ppm 혹은 bithionol 100 ppm에서 1 시간동안 약욕한 결과 모든 실험어에서 100% 치료효과를 나타내었으며, 이보다 더 낮은 농도(formalin 50 ppm, 100 ppm 및 bithionol 25 ppm, 50 ppm)에서의 약욕에 의해서도 Ichthyobodo sp.의 감염강도를 유의적으로 감소시켰다. 그러나 bronopol을 이용한 약욕 및 bithionol의 경구투여는 대조구에 비해 유의적인 치료효과를 나타내지 않았다.