• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.3
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• pp.303-307
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• 2006

The effects of starvation on histological changes in hepatocytes and the intestinal epithelium in the olive flounder, Paralichthys olivaceus were examined. The starved group was not fed for 12 weeks, whereas the fed group was given food. Food deprivation resulted in a significant decrease in hepatocyte nucleus size and nuclear height in the intestinal epithelium (P<0.05). In the starved group, pronounced degenerative changes were seen in the histology of hepatocytes and the intestinal epithelium; the tissue morphology was irregular and the nuclei were stained basophillic, shrunk irregularly, and very compact. These results suggest that histological changes in hepatocytes and the intestinal epithelium can be used as an indicator of starvation in the olive flounder. In addition, the data are interpreted in detail and some biologically important relationships are discussed.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.116-117
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• 2002

Olive flounder and Black rockfish comprises around 90％ of the total fish culture in Korea. Most of the olive flounder is consumed as raw fish meat “saengseonhoe”, as like a sashimi in Japan. Also, texture is particularly a important factor which determine the quality of raw fish meat in Korea. Many works have attempted to improve of texture such as arai, electrical stimulation and compulsory exercise of fishes. (omitted)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.253-254
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• 2001

Aquaculture production of Hounder has been increased in the last decade in Korea. However, moist pellet primarily made of raw fish has been used as feed for flounder. Therefore, for further expansion of flounder farming, it is essential to employ practical formulated feeds which can support reasonable growth. Several studies on nutrition (Lee et al., 2000) and utilization of some plant protein source as a substitute for fish meal (Kikuchi, 1999) have been conducted for flounder diets. (omitted)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.869-873
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• 2014

Cardiorespiratory variables were measured in flounder Paralicthys olivaceus exposed to acidified seawater equilibrated with a gas mixture containing 5% $CO_2$ gas for 72 h at $20^{\circ}C$. It was found that $CO_2$ produced a significant increase in arterial $PCO_2$ ($PaCO_2$) and significant decreases in arterial pH (pHa). $CO_2$ transiently increased heart rate within 30 min of exposure. After cardiac output was elevated by the increase in heart rate within 30 min, was then reduced by the decrease in both stroke volume and heart rate. The heart responses of flounder differ from those of yellowtail to high $CO_2$ environment.

• Food Science and Preservation
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• v.18 no.5
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• pp.746-754
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• 2011

This study analyzed the taste components of dorsal muscle and fin muscle collected from olive flounder cultured with extruded pellet (EP) compared with those of olive flounder cultured with raw fish moist pellet (MP) as a control. The olive flounder in this study were cultured for 10 months with either the formulated extrude pellets (FEP), commercial extruded pellets (CEP) or the MP feed, and the average weight was 1.15 kg. The major nucleotides and related compounds in the dorsal muscles of the fish fed with MP, CEP and FEP diets were AMP and IMP. The fin muscle of the olive flounder contained the largest amounts of IMP($5.91{\mu}mol/g$). The K value of the dorsal muscle in olive flounder fed with MP, CEP and FEP showed 9.63%, 9.83% and 5.84%, respectively. The free amino acids in the dorsal muscle of olive flounder showed significantly differences in the composition depending on the feed, but the distribution of free amino acids showed similar patterns. Among free amino acids, taurine showed the highest content in all the experimental groups, and the asparagine and citrulline contents were significantly higher in the groups fed with CEP and FEP than in the group fed with MP. The significant differences were observed in the contents of specific free amino acids in dorsal muscle and fin flesh depending on the feed for cultured olive flounder.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.551-553
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• 2005

Carbonic anhydrase III was found in liver of flounder, Limanda yokohamae. Protein was isolated from cytosolic extracts and identified using SDS-PAGE and isolectric focusing. Specific protein bands with molecular weight of 30 kDa and pIs of 7.0 and 6.5 were detected by Western blotting. This is the first report of identification of carbonic anhydrase III from L. yokohamae.

• Journal of fish pathology
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• v.20 no.3
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• pp.257-267
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• 2007

The hypo-salinity effects on fertilized eggs, embryos and larvae were investigated in olive flounder (Paralichthys olivaceus) obtained from hatcheries in Cheju-Island, Yeosu and Chungnam. Those were treated to eight concentration; 0, 3.4, 6.7, 10.1, 13.4, 20.2, 27.4 and 33.6 ‰. It was not discrepancy in the survival rate and hatching success rate of fertilized embryos obtained from different regions. Also, in the larvae, the regional difference was not appeared. The survival rate and hatching ability of embryos significantly diminished in the lower groups than 13.4 ‰ compared to 33.6 ‰. After fertilization, namely embryos are tolerant of a wide range of salinity (13.4 - 33.6 ‰). Reduced salinity induced an increase of the malformed embryo and larvae including various deformities; irregular embryos membrane (or yolk sac depression), fin erosion and swim bladder inflation in the flounder embryo. The hatching success of embryos was significantly reduced in lower salinity than 13.4 ‰. Notably, the reduction of larval survival rate significantly was observed in ≤10.1 ‰ treated groups with the same manner of survival rates of the embryos. Additionally, olive flounder was found to be adequate model for measuring external impulses because there are no the regional differences.

• Journal of fish pathology
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• v.6 no.2
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• pp.197-204
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• 1993

Flounder culture has been developed mainly in the western parts of japan, and, to date, following six bacterial diseases have been reported. Bacterial white enteritis occurs in 16 to 30-day-old flounder larvae and often causes mass mortality in seed production. Bacterium named Vibrio sp. INFL invades and multiplies in the mucosae of posterier part of intestine, and causes desquamative enteritis. Gliding bacterial disease occurs mostly in juvenile stage and in spring to summer. Diseased signs are partial discoloration and erosion of skin and fins. Histologically, epidermis are removed, and the causative bacterium, Flexibacter maritimus, multiplies on the surface of demis and invades into the muscular tissue. Vibriosis caused by Vibrio anguillarum and related organisum is one of the well-known diseases among marine fish. Outbreaks of the disease in flounder culture are relatively few, but mass mortalities in fingerlings due to the disease were reported. An outbreak of nocardiosis in the autumn of 1984 has been reported, but since then the disease scarcely occurred. The disease is characterized by formation of abscesses under the skin and white nodes in the gill, heart, spleen and kidney. Streptococcicosis occurs frequently in recent years. Beta-hemolytic streptococcus is the causative bacterium, which possesses the same biochemical and serological characteristics as $\beta$-streptococci isolated from some marine and freshwater fish, and is seemed to related to Streptococcus iniae. Edwardsiellosis is the disease that causes most damage in flounder culture in Japan. Characteristic symptoms are swelling of abdomen and intestinal protrusion from the anus due to accumulation of ascites. Edwardsiella tarda, a well-known pathogen of freshwater fish, is the causative bacterium of the disease.

• Journal of fish pathology
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• v.6 no.2
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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.

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.161-166
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• 1999

The rigor-mortis progress of cultured olive flounder spiked at the brain started much faster than that of wild one. They attained full rigor state after 30 hrs at $0^{\circ}C$, 36 hrs at $5^{\circ}C$ and 50 hrs at $10^{\circ}C$ in the cultured flounder, while after 36 hrs at $0^{\circ}C$, 50 hrs at $5^{\circ}C$, and 60 hrs at $10^{\circ}C$ in the wild. ATP concentration in the muscle was around $5.9\mu mol/g$ for wild and $6.2\mu mol/g$ for cultured flounder. ATP breakdown progressed rapidly in $0^{\circ}C$ samples, followed by $5^{\circ}C$ and $10^{\circ}C$ samples. $Mg^{2+}$-ATPase activity of myofibrillar protein in the presence of 0.25mM CaCb was higher in cultured myofibri1lar protein than in wild one. $Mg^{2+}$-ATPase activities of myofibrillar protein increased during storage in samples stored at $0^{\circ}C$ and $5^{\circ}C$ while decreased in samples stored at $10^{\circ}C$. The level of breaking strength of muscle immediately after death was higher in the wild muscle than in the cultured muscle. The breaking strength reached maximum level at 10 hrs after death in both samples.