• Fisheries and Aquatic Sciences
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• 제6권4호
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• pp.225-227
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• 2003

Acetylcholinesterase (AChE) activity is a potential biomarker for phenanthrene exposure in aquatic organisms. Olive flounder (Paralichthys olivaceus) were exposed to three different concentrations (0.5, 1.0 and 2.0, uM) of phenanthrene for four weeks. AChE activities in the brain, heart and eyes were documented. Inhibition of AChE activity was found significant in flounder treated with a concentration greater than $1.0 {\mu}M$ of phenanthrene. This indicates that a chronic exposure to phenanthrene induces damage in various organs (brain, heart and eyes) and changes of AChE activities might be a useful biomarker to assess the impacts induced by polycyclic aromatic hydrocarbon (PAH). Evidence from this study confirms that the measurement of AChE in the brain and eyes of flounder is a valuable tool that along with other biomarkers can maximize an ecotoxicologists' confidence in assessing the impacts of oil and PAH pollution in the aquatic environment.

• Animal cells and systems
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• 제8권4호
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• pp.329-333
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• 2004

Japanese flounder (Paralichthys olivaceus) head kidney (HK) leukocytes were incubated with $10^3$ to $10^{-3}$ ng levamisole/ml for 4, 24 or 48 h and then assayed for their natural cytotoxic activity against xenogeneic tumor cells. This activity was slightly increased after 24 h of incubation. In a second experiment, fish were fed 0, 75, 150 or 300 mg levamisole/kg diet for 10 consecutive days. The fish were then fed a commercial non-supplemented diet and sampled 0, 1, 2, 3, 4 or 6 weeks post-administration of levamisole. The cytotoxic activity was found to be increased with increasing levamisole dose and remained greatly enhanced until the end of the experiment. In conclusion, levamisole enhanced flounder natural cytotoxic cell activity both in vitro and in vivo and had a great lasting action when administered by feeding.

• 한국어류학회지
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• 제19권2호
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• pp.88-92
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• 2007

Marine birnavirus (MABV)에 무증상적으로 감염된 넙치 (Paralichthys olivaceus) 치어에 면역억제제의 일종인 Dexamathasone을 투여하였을 때 MABV의 감염강도에 영향을 미치는가를 조사하였다. Real time PCR 분석결과 dexamethasone을 투여한 그룹이 생리식염수를 주사한 그룹 및 no handling 그룹에 비해 유의적으로 낮은 Ct 값을 나타냈으며, 또한 semi-quantitative RT-PCR 분석결과에 있어서도 dexamethasone을 주사한 그룹이 대조구 그룹들에 비해 MABV 유전자가 유의적으로 높게 증폭되는 것으로 나타났다. 이러한 결과로부터 dexamethasone 투여가 넙치 치어에 감염된 MABV의 복제를 증가시킴을 확인하였다.

• 한국수산과학회지
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• 제36권2호
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• pp.107-112
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• 2003

Effect of PCBs on the skin and gill development of olive flounder, Paralichthys olivaceus were investigated by histological methodology and morphometric data. The olive flounder were exposed to limit concentration of effulent of PCBs (3.0 ${\mu}g/L$) for 60 days. Skin development can be classified into four stages: SSEL (simple squamous epithelial layer), MCA (mucous cell appearance) & CCA (club cell appearance) DLA (dermal layer appearance), and SEL (startification of epidermal layer) stages. Gill development had five stages: GFA (gill filament appearance), IGFE (identification of early gill filament epithelial cell) MCA (mucous cell appearance), PCA (pillar cell appearance), and FGL (formation of gill lamella) stages. The periods of structural completion of skin and gill were 22-30 days and 23-30 days after hatching in the exposure group respectively. The process of development of skin and gill of the exposure group was very similar to that of the control group. Therefore, PCBs (3 ${\mu}g/L$) have no influence on the development of skin and gill in the larval stage of olive flounder.

• 한국수산과학회지
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• 제36권6호
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• pp.614-618
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• 2003

This study was conducted to evaluate the effects of dietary medicinal herb residues (MHR) on the growth and body composition of olive flounder (Paralichthys olivaceus). Two replicate groups of olive flounder with initial mean body weight of $18.7\pm0.3\;g$ were fed 8:2 (raw fish and commercial compound meal ratio)MP diet containing $0\%,\;50\%,\;10\%,\;15\%\;and\;20\%$ MHR for 7 weeks. Weight gain and feed efficiency increased in the $5\%\;and\;10\%$ group as compared to the control group, whereas they decreased in the $15\%\;and\;20\%$ groups. Moisture, crude protein, and crude ash content of the whole body were not significantly different between experimental groups, whereas crude lipid content of the $5\%\;and\;10\%$ groups were significantly higher than that of the $10\%\;and\;20\%$ groups. The results indicate that the addition of $5\%\;and\;10\%$ MHR in 8:2 MP diet can improve growth and feed efficiency, but addition of more than $15\%$ were not effective.

• 한국어병학회지
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• 제6권2호
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• pp.191-195
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• 1993

With the rapid progress in seed production techniques, aquaculture production of economically important species of marine fish has been accelerated in Japan. Howecer, mass mortalities due to viral infections as well as other microbial infections have often occurred during the seed production and grow-out stages. Among these diseases, four viral diseases have been known in cultured Japanese flounder (Paralichthys olivaceus) since around 1980. In this paper, viral diseases of cultured flounder in Japan are briefly reviewed, with special attention to two viral diseases. viral epidermal hyperplasia and rhabdovirus infection which are relatively important because of their frequent occurrence. Viral epidermal hyperplasia is characterized by fin opacity and associated with high mortality in larval flounder Electron microscopy of affected epidermal cells and transmission experiments with tissue filtrates demonstrated that the disease was caused by a herpesvirus but the agent has not been isolated in fish cell lines. On the other hand, rhabdovires infection occurrs in juvenile and production size fish with hemorrhage in the skeltal muscle and fins, congestion of the gonads, and ascites. A rhabdovirys was isolated in RTG-2 cells from the diseased flounder as a causative agent, which was designated hirame rhabdovirus (HRV) or Rahbdovirus olivaceus. HRV is serologically distinguishable from other known fish rhabdoviruses. Intensive researches on these viral diseases started in 1980th. but properties of the causative agents and infection mechanisms have not been fully investigated. This results in difficulty in controlling these diseases.

• 한국수산과학회지
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• 제53권4호
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• pp.628-636
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• 2020

Streptococcosis in the olive flounder Paralichthys olivaceus can be caused by Streptococcus parauberis. We compared three routes of administration for experimental injections of the S. parauberis 19FBSPa0003 strain in the olive flounder. Pathological changes were observed during the experimental infection. Inflammation of the serous membrane in the liver, intestine, spleen and heart was the major pathological change found in the infected olive flounder. No mortality was observed in fish that received intraperitoneal (IP) injection at less than 1×10⁴ colony-forming unit (CFU)/fish. The lethal dose 50 for olive flounder, given an intravenous (IV) injection, was 7.94×10⁴ CFU/fish. Fish with a higher concentration of IV injected S. parauberis (1×10⁸ CFU/fish) died within a maximum of two days. However, serious necrosis and bacterial proliferation in ellipsoidal cells of the spleen and heart tissues were found in moribund or dead fish, 1-2 days after IV injection. Similar histopathological signs were observed in olive flounder inoculated by subcutaneous (SC) infected and naturally infected. In addition, SC was also strongly associated with bacteria concentration and cumulative mortality rate. Based on these results, SC is the recommended method for artificial infection by S. parauberis in the olive flounder.

• 환경생물
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• 제21권2호
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• pp.114-119
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• 2003

$PCB_{s}$ 농도 3.0${\mu}g \; L^{-1}$ 노출에 따른 넙치의 혈액학적 변동을 조사하기 위하며 60일간 침지실험을 실시하였다. PCBs에 노출된 넙치의 무기성분 중에 혈장 magnesium과 inorganic phosphorus는 유의적 변동이 없었으나, calcium은 대조구에 비해 유의한 감소를 보였다. 또 한 유기성분 중에 total protein과 albumin은 노출 20일 째부터 유의한 감소를 보여 실험 종료시가지 이러한 감소는 지속되었고, glucose는 노출 40일 이후 유의한 증가를 나타내었다. 혈장 ALP와 GPT의 활성도는 노출 20 일 이후부터 대조구에 비해 유의한 증가를 나타내었고, GOT는 노출 40일 이후 유의한 증가를 나타내었다. 이상의 결과는 해양에 3.0${\mu}g \; L^{-1}$의 PCBs농도가 존재할 경우 넙치의 혈액학적 변동을 야기할 수 있음을 의미한다.

• 한국수산과학회지
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• 제47권5호
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• pp.630-636
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• 2014

To investigate the characteristics of hybrid eggs and larva produced by olive flounder Paralichthys olivaceus females and starry flounder Platichthys stellatus males, we examined the developmental speed of hybrid eggs at different water temperatures. The developmental speed of hybrid eggs tended to increase with increasing water temperature. Specifically, the hatching times were 91 hrs, 62 hrs and 43 hrs at $10^{\circ}C$, $15^{\circ}C$ and $20^{\circ}C$, respectively. The mean biological minimum temperature of the hybrid was $1.3^{\circ}C$, which is in between that of the olive flounder and the starry flounder. In high water temperatureseasons, slower growth was observed in hybrids of the starry flounder which is a coldwater fish.

• 한국어병학회지
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• 제23권3호
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• pp.379-388
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• 2010

This paper presents a computer program for easy and rapid disease diagnosis of olive flounder diseases. To design the program, standard diagnosis process of the 14 olive flounder diseases was first setup, then implemented four-steps diagnosis program. To run program, first input fundamental information such as water temperature, size of the diseased fish. Then sequentially, three categories of key factors for disease diagnosis which include external clinical signs, internal clinical signs and microscopic observations are selected. When a user selects the observed signs of olive flounder from the listed options, the program provides maximum 5 presumed disease candidates in order. The disease information, treatment and prevention methods are provided by connected web server through internet. The program would support fish doctors and farmers by providing easy and rapid diagnosis of diseased olive flounder.