• Journal of fish pathology
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• v.22 no.1
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• pp.9-14
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• 2009

Fifteen diseased rockfish (Sebastes schlegeli) were collected from 4 net-cage farms in Huksan island. Some round transparent nodules were observed on gill filaments in fish. Bacteriological and histopathological examinations on the diseased fish were performed. Any pathogenic bacteria could not be isolated from the internal tissues and histopathological alterations were not found in any of the tissues except the gills. Rock fish were infected with epitheliocystis, Microcotyle sebastes and unknown aetiology on the gills. Cysts of epitheliocystis measuring 44.1-68.9 $\mu{m}$ in diameter were mainly found in the distal portion of the gill filaments and sometimes in the middle portion. But host responses were moderate in spite of formation of the epithelial cysts. Some Microcotyle sebastes captured the secondary filaments with clamps on the opisthohaptor. Attachment of the parasites provoked epithelial proliferation and resulted in gill lamellar fusion.Cysts of unknown origins measuring 26-425 $\mu{m}$ in diameter were found in the cartilage of gill filaments. These cysts contained eosinophilic materials and proliferation of cartilage cells was confirmed around the cysts. But there was no significant pathological changes associated with the presence of the cysts except enlargement of the gill filament with the cysts.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.195-202
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• 2011

This study analyzed and modeled the relationships between the probabilities of two exotic species occurrence (i.e. largemouth bass and blue gill) and environmental factors such as climatic and geographical variables using Generalized Additive Models (GAM), Generalized Liner Models and Classification Tree Analysis (CTA). The most moderate occurrence probability of largemouth bass was predicted using GAM with an area under the curve (ADC) of 0.88 and Kappa of 0.42, while those of blue gill was suggested by using CTA with an AUC of 0.92 and Kappa of 0.44. The most significant environmental variable in terms of changes in deviance for both species was the annual air temperature for the occurrence probability. Dams had stronger effect on the occurrence of largemouth bass than blue gill. Model development and prediction for the occurrence probability of fish species and richness are necessary to prevent further spread of exotic fishes such as largemouth bass and blue gill because they can threaten habitats of native river ecosystem through various mechanisms.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.533-538
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• 2015

This study was conducted to examine the effect of salinity on the early embryonic development stage of boreal digging frogs (Kaloula borealis). An experiment was carried out with the eggs of K. borealis mating couples laid along the coastal zone of Jeju Island in June 2013. The salinity was set to 0, 1, 3, 5, and 7 ‰, respectively. The survival and growth of the larvae at various stages from the egg phase to the closing of their external gills phase were observed. In another experiment, tadpoles in internal gill stage were placed in solutions with salinity of 0, 1, 3, 5, and 7 ‰, respectively, and their survival rate and growth rate were observed, and then the results of the two experiments above were compared. The results showed that in egg and external gill stage, there was no significant difference in survival rate in 3 ‰ solution, though there was low survival rate in 5 ‰ solution. Further, all the eggs were dead in 7 ‰ solution, so it appeared that solutions with salinity of 5 ‰ or higher affect the survival of K. borealis in the early embryonic development. Larvae in the internal gill stage showed no significant difference in survival rate from the control group up to a salinity of 5 ‰, but when placed in a solution of over 7 ‰ salinity, the survival rate decreased. The growth rate also slowed down with the higher salinity. It appeared that in both the external gill stage and the internal gill stage in 5 ‰ solution, the growth rate decreased significantly compared to the control group. From this study it is concluded that higher salinity values have a significant impact on the survival and growth of the K. borealis larvae and this finding can be used to conserve K. borealis species that are decreasing in number due to the side effects of development in coastal areas.

• Proceedings of the KIEE Conference
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• 1979.08a
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• pp.53-55
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• 1979

• The Journal of Fisheries Business Administration
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• v.7 no.2
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• pp.23-61
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• 1976

• The Korean Journal of Air & Space Law and Policy
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• v.6
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• pp.43-83
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• 1994

• The Korean Journal of Pain
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• v.29 no.4
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• pp.215-216
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• 2016

• Kyungpook Mathematical Journal
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• v.12 no.1
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• pp.61-68
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• 1972

• The Korean Journal of Air & Space Law and Policy
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• no.spc
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• pp.201-223
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• 2007

• The Korean Journal of Pain
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• v.9 no.1
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• pp.14-25
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• 1996