• 한국양식학회지
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• 제16권2호
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• pp.99-103
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• 2003

Olive flounder (Paralichthys olivaceus) was exposed to water-borne phenanthrene for 4 weeks. After the exposure for 2-weeks, hepatic cytochrome P450 contents were significantly elevated. Induction of hepatic ethoxy resorufin-O-deethylase (PROD) activity was significantly increased in flounders treated with 1.0 and 2.0 $\mu$M phenanthrene, compared to untreated group and 0.5 $\mu$M treated group. However, there were no significant changes in pentoxyresorufin-O-deethylase (PROD) activity in hepatic microsome of all the phenanthrene-treated groups, compared to the untreated group. Phenanthrene has the potential to induce cytochrome P450 and EROD enzyme of the olive flounder.

• Ocean and Polar Research
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• 제32권4호
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• pp.483-488
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• 2010

Since 2000 fry releasing programs in Korea have significantly expanded in order to support the commercial fishing industry through recruitment enhancement of targeted species. Here we investigate the economic effectiveness of the Olive flounder (Paralichthys olivaceus) fry releasing program in Korean waters. The market survey method was used in our analyses. Results show that the B/C ratio, as an indicator of economic evaluation, is 2.56 in the East Sea region, 9.45 in the South Sea region, and 1.34 in the West Sea region, which indicates that the fry releasing program is economically feasible but the economic effectiveness varies from region to region.

• Fisheries and Aquatic Sciences
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• 제7권1호
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• pp.29-33
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• 2004

The potential of phenanthrene to induce xenobiotic responses was investigated. Olive flounder (Paralichthys olivaceus) was exposed to different levels of phenanthrene $(0.5,\;1\;and\;{\mu}M)$ for 4 weeks, Gill CYP450 content and EROD (ethoxyresorufin O-deethylation) activity were found to be significant in the flounders treated with the higher concentration of phenanthrene $(>1.0\;{\mu}M)$, however, there were no significant changes in gill PROD (penthoxyresorufin O-deethylation) activity in all treated group compared to the controls. This study demonstrated that phenanthrene has potential to induce gill cytochrome P450 and EROD enzyme in olive flounder.

• Fisheries and Aquatic Sciences
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• 제15권3호
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• pp.215-220
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• 2012

The effects of inorganic mercury on hematological parameters and hepatic oxidative stress enzyme activity were studied in olive flounder Paralichthys olivaceus. Fish were injected twice intraperitoneally with mercuric chloride (2, 4, or 8 mg Hg/kg BW). The major hematological findings were significant decreases in the red blood cell count, hematocrit value, and hemoglobin level in olive flounder exposed to 8 mg Hg/kg BW. Remarkably low levels of calcium and chloride, and reduced osmolality, were also observed at 8 mg Hg/kg BW. In hepatic tissue, significant increases in glutathione peroxidase and catalase activity were observed above 4 mg Hg/kg BW Inorganic mercury also increased glutathione S-transferase and glutathione reductase activity at 8 mg Hg/kg BW in hepatic tissue. The present findings suggest that exposure to a low concentration (${\geq}4$ mg Hg/kg BW) of inorganic mercury can cause significant changes in hematological and antioxidant parameters.

• 한국수산과학회지
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• 제56권2호
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• pp.243-252
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• 2023

Fluctuations in the price of aquaculture products have recently intensified. In particular, wholesale price fluctuations are adversely affecting consumers. Therefore, there is an emerging need for a study on forecasting the wholesale price of aquaculture products. The present study forecasted the wholesale price of olive flounder Paralichthys olivaceus, a representative farmed fish species in Korea, by constructing multivariate long-short term memory (LSTM) and gated recurrent unit (GRU) models. These deep learning models have recently been proven to be effective for forecasting in various fields. A total of 191 monthly data obtained for 17 variables were used to train and test the models. The results showed that the mean average percent error of LSTM and GRU models were 2.19% and 2.68%, respectively.

• 한국수산과학회지
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• 제47권4호
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• pp.406-412
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• 2014

To evaluate the influence of burrowing substrate on the rearing performance and ambicoloration of cultured flounder, Paralichthys olivaceus, we compared the daily food intake (DFI), feed efficiency (FE), survival, growth, proportion of pigmented skin on the blind side, and proportion of ambicolored fish. We reared juvenile flounders [total length (TL) $4.46{\pm}0.06cm$, body weight (BW) $0.77{\pm}0.03g$] in dark-green fiberglass-reinforced plastic (FRP) aquariums without (control) or with gravel substrate at a density of 200 fishes/ton for 120 days. While there was no difference in survival rate or growth, the DFI was lower and FE higher in the group raised with substrate than in the control. The proportions of pigmented area on the blind side and ambicolored fish were significantly higher in the control tank. Therefore, the supplement of substrate on the aquarium bottom positively affects the feeding efficiency, and inhibits abnormal pigmentation on the blind side in flounder farming at high density.

• 한국수산과학회지
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• 제49권1호
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• pp.45-52
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• 2016

This experiment investigated changes in metabolic rate (MO₂), critical oxygen saturation (S_crit), and blood chemistry of olive flounder Paralichthys olivaceus exposed to progressive hypoxia and returned to normoxic water at 20°C. The normoxic standard metabolic rate (SMR) and routine metabolic rate (RMR) were 69.5-83.9 and 70.2-156.4 mg O₂ kg^-1h^-1, respectively based on fish weight. S_crit was 31.0% dissolved oxygen (DO) at 20°C. After returning the fish to 70% DO following exposure to hypoxia (20% DO), MO₂ increased two-fold compared to the normoxic SMR and then decreased into the range of the RMR with time. Blood PO₂ and plasma lactate decreased significantly after exposure to hypoxia (20% DO) and then increased as ambient oxygen saturation decreased. Cortisol levels increased as ambient oxygen saturation decreased, but the levels decreased rapidly in the range of the normoxic control when the fish were returned to ambient water with 70% DO. Plasma glucose levels increased when the fish were returned to normoxic water after exposure to a progressively more hypoxic condition.

• 한국수산과학회지
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• 제53권5호
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• pp.740-751
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• 2020

In the aquaculture industry, few studies are analyzing big data for intrinsic meaning. Fishcare Laboratory (www.fishcare.kr) diagnostic data from 2016-2018 was analyzed for scuticociliatosis (caused by Miamiensis avidus) outbreak patterns in cultured olive flounder Paralichthys olivaceus in Jeju, Korea. The scuticociliatosis monthly occurrence ratio is reported in the summary table after preparing and filtering the basic dataset model. Nonparametric test results suggest differences in the water temperature, body length, and weight between groups with and without scuticociliatosis. Data distribution visualization revealed that shorter body length and lighter weight increased the occurrence of scuticociliatosis. The association rule mining technique was applied to determine the primary clinical signs of mixed scuticociliatosis and bacterial infections. Venn diagrams were used to report clinical signs and suggest commonalities. These results may help diagnose and treat fish and provide a decision-making reference.

• 한국어병학회지
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• 제15권1호
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• pp.37-42
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• 2002

Effect of mercury (Hg) toxicity on survival, growth, feed efficiency and oxygen consumption were examined in the juvenile olive flounder. Paralichthys olivaceus. Fishes were exposed to sublethal concentrations of Hg ranging from 0 to 0.13mg/L for 6 weeks. Hg reduced survival rate in a concentration and exposure period-dependent way and suddenly reduction occurred at Hg concentrations greater than 0.05mg/L after 6 weeks. Growth rate and feed efficiency also significantly decreased at greater than 0.028 and 0.05 mg/L respectively. Oxygen consumption rate was significantly decreased to 25 and 32% than that of the control at the Hg concentration of 0.05 and 0.13 mg/L respectively. These results suggest that Hg toxicity inhibit physiological function including growth, feed efficiency and oxygen consumption in the juvenile olive flounder, resulting in survival failure at high concentration.

• 한국해양생명과학회지
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• 제2권1호
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• pp.12-19
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• 2017

급격한 수온의 변화는 어류의 생리학적인 측면에서 스트레스를 유발한다. 본 연구에서는 넙치(Paralichthys olivaceus)로부터 각 수온별(9, 12, 15, 18 및 21℃) 조건에 따라 24 및 48시간 동안 노출시킨 후에, 혈액생리학적 분석, 스트레스 단백질로 알려진 Hsp70 mRNA 발현 및 산소 소비량을 조사하였다. 혈액학적 분석에서 hematocrit (Ht) 및 hemoglobin (Hb), 혈장 코티졸 및 글루코스의 변화, aspartate aminotransferase (AST) 및 alanine aminotransferase (ALT), NH₃, 삼투질농도(osmolality) 및 총단백질(total protein, TP)은 9℃ 및 12℃에서 다른 수온별 실험구에 비해 대부분의 항목에서 유의적인 차이를 보였다. Hsp70 mRNA 발현은 9℃ 및 12℃에서 다른 실험구에 비해 높은 발현량을 확인하였고, 산소소비량은 9℃ 및 12℃에서 21℃에 비해 낮았다. 이러한 결과는 넙치 종자의 장거리 수송을 위한 수온자료로 활용할 수 있다.