• Journal of fish pathology
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• v.8 no.2
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• pp.91-98
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• 1995

During 1993 and 1994, some mortalities of flounder(Paralichthy olivaceus) fry were recorded in several fish farms and viruses were isolated from 3 of the farms. Electron microscopic examination revealed that the virus particles were hexagonal and unenveloped with an average diameter of 50 to 55nm. Serological and molecular properties of these isolates were examined. The viral RNA and polypeptides patterns on electrophoresis, as well as neutralization test results, showed that these isolates were birnaviruses and two were closely related to infectious pancreatic necrosis virus(IPNV) serotype AB and one was to IPNV serotype SP. This is the first isolation of birnaviruses from marine fish in Korea.

• Journal of Aquaculture
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• v.12 no.1
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• pp.31-38
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• 1999

The dietary value and fatty acids composition for the hatched neonates from the resting eggs of marine roofers, Brachionus plicatilis and B. rotundiformis were compared with that for mass-cultured rotifers (control) by feeding them to larvae of flounder (Paralichthy olivaceus) and parrot fish (Oplegnathus fasciatus). Resting eggs were mass-produced in $1~4m^3$tanks by feeding Chlorella sp. and baker's yeast. The B. plicatilis and B. rotundiformis eggs were preserved at $5^{\circ}C$ in darkness for 3 and 5 months, respectively, and hatched at $28^{\circ}C$ under continuous light. The hatched neonates from the resting eggs and mass-cultured rotifer, which was used as a rontrol were fed to fish larvaes. The growth and survival rates of parrot fish larvae fed on the neonates from the resting eggs of B. rotundiformis were similar to those of fish larvae fed on the control rotifer. And the growth and survival rates of the flounder larvae with neonates from the resting eggs of B. plicatilis were similar or higher than those fed the control rotifer. Also the fatty acids composition of the neonates from the resting eggs of B. plicatilis and B. rotundiformis were similar to those from the control rotifers. This results showed that the hatched neonates from resting eggs of rotifer could be used as an effective diet for flounder and parrot fish larvae.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.283-289
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• 2003

The effect on kidney, gill, and hepatopancreas of juvenile olive flounder, Paralichthys olivaceus were investigated by histological method under limit concentration of effulent of PCBs for 60 days. The free surface of epithelial cell layer in the renal tubules of kidney showed a strong positive reaction in alcian blue during all exposure period. There were also observed swelling of hemocyte in glomerulus and macrophage. At 60 days after exposure, epithelium of the renal tubules was fused and some of organism $(20\%)$ showed damage of glomerulus and eosinophlic cell in epithelium of the renal tubules. The phenomena such as the activation and increase of the chloride cell, and swelling of hemocyte in the capillary of gill were observed during all exposure period. At 60 days after exposure, swelling of the gill filament and mucous cell appeared in gill and some of organism $(30\%)$ showed swelling of the gill lamellar. Swelling of hemocyte in the capillary of hepatopancreas was observed and the free surface of epithelial layer of the bile duct showed positive reaction in alcian blue during all exposure period. Degenerated zymogen in the pancreas and swelling of the hepatocyte were occurred at 60 days after exposure.