• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.290-291
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• 2002

• Korean Aquaculture
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• v.16 no.2
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• pp.4-11
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• 2004

• Proceedings of the Korean Aquaculture Society Conference
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• 2002.08a
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• pp.179-180
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• 2002

• Journal of Aquaculture
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• v.18 no.1
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• pp.19-25
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• 2005

This study was performed to investigate the optimum density for the intensive mass production of cyclopoid copepod, Paracyclopina nana in terms of nauplii and adults production. Effect of three development stages on the fecundity of adult female for nauplii production, survival rate of P. nana nauplii with different initial nauplii culture densities for adults production and cannibalistic feeding behavior of P. nana was examined, respectively. The fecundity of adult female by different female, copepodite ana nauplii density in 2 ml water volume decreased with the density of adult female, but was not affected by the density of either copepodite or nauplii. The average daily nauplii production for a adult female in 8 L water volume was $2.3{\times}10^5$ individuals with the incubation density of 7 adult females/ml, and this average value was significantly higher than those values of 0.6 to $1.7\times10^5$ individuals with the incubation density of 1,3,5, 10 adult females/ml (P<0.05). Survival rate of P. nana nauplil with different initial nauplii culture densities in 5 L vessels for 15 days were 32.7, 30.7, 28.9 and $23.0\%$ with the culture density of 50, 100, 150 and 200 inds./ml, respectively, but these were significantly higher than those of values 19.7 and $18.4\%$ with the culture density of 250 and 300 inds./ml (P<0.05). Cannibalistic behavior of P. nana adults on their offspring was observed, but the behavior decreased when phytoplankton was supplemented though there was no statistical difference (P>0.05). These results may indicate that P. nana is adaptable to the hatchery conditions and this species is cultured at the high densities. Optimum culture density for nauplii and adults production of P. nana were 7 adult females/ml and 200 nauplii/ml, respectively.

• Proceedings of the Korean Aquaculture Society Conference
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• 2005.05a
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• pp.32-33
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• 2005

• Proceedings of the Korean Aquaculture Society Conference
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• 2004.05a
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• pp.224-225
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• 2004

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.1
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• pp.12-19
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• 2005

This study investigated the productivity and growth of copepods, Sinocalanus tenellus 2 strains, Paracyclopina nana 3 strains, Apocyclops royi 2 strains, Tachidius triangularis 1 strain and Tigriopus sp. 1 strain at different temperatures $(24,\;28\;and\;32^{\circ}C)$ under 15 psu and various salinities (10, 20, 30 psu) at $28^{\circ}C$ for an individual culture. And the mass culture was carried out to evaluate the production of these copepods in the 500 mL vessel. For an individual culture of copepod, survival period of a brood female tended to increase with the decrease of temperature, but was not significantly influenced by salinity. With an increase of temperature and a decrease of salinity, maturation period of nauplii in all species tended to decrease. Total nauglii production from a broodo female at $24^{\circ}C$ was higoher than that from a brood .female at either 28 or $32^{\circ}C$ for S. tenellus and at $32^{\circ}C$ than either 24 or $32^{\circ}C$ for A. royi Haenam stram, but was not influenced by temperature for another copepods. And total nauplii production from a brood female at 10 and 20 psu tended to be higher than that from a brood female at 30 psu, expect for Tigriopus sp. and P. nana Hwajinpo strain. Total nauplii production from a brood female was the highest in Tigriopus sp. (350 nauplii) at $28^{\circ}C$ under 20 psu, followed by A. royi Haenam strain (187 nauplii) at $32^{\circ}C$ under 15 psu and P. nana Hwajinpo strain (152 nauplii) at $24^{\circ}C$ under 10 psu. In the mass culture of each copepod, P. nana was the most productive (26.6 mg dry weight) and this value was two and four times higher than productivity of Tigriopus sp. and A. royi, respectively.

• Ocean and Polar Research
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• v.36 no.2
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• pp.199-208
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• 2014

Copepods are a major food source for marine fish larvae in nature. Many studies on copepods culture have been conducted to develop a new live food for the seedling production of marine fish larvae. But fish farmers still depend on rotifer and Artemia nauplii. This study was carried out to find suitable copepods as live food for the larvae in hatchery. Eight species of copepods (1 calanoid, 2 cyclpoid, 5 harpacticoid) that were fed Isochrysis galbana were examined in terms of the size of nauplii, fecundity, amino acids, and fatty acids contents. These species were divided into small (nauplii length 46-86 ${\mu}m$) and large (nauplii length 120-188 ${\mu}m$) size group. Nitokra spinipes in the small group and Tigriopus japonicus in the large group showed the highest fecundity with 151.1 and 139.6 nauplii production per gravid female, respectively. With regard to nutrients, essential amino acids were the highest with 21.2% in cyclopoid Paracyclopina nana in the small group and n-3 HUFA were the highest in calanoid Pseudodiaptomus inopinus (8.5 ${\mu}g/mg$) in the large group and P. nana (8.8 ${\mu}g/mg$). In terms of the size, fecundity, and nutritional value of copepods examined in this study, N. spinipes and P. nana seem to be suitable copepod species to develop as a new live food for small mouth fish larvae.

• Journal of Environmental Impact Assessment
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• v.26 no.3
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• pp.207-216
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• 2017

Several bioassays have been performed for assessment of the impact of polluted sediments. The direct exposure method using sediments is limited by difficulty controlling feeding and its effects on organisms. Furthermore, only macro-organisms and benthic organisms are used. To evaluate the potential application of sediment elutriate as a complementary strategy for impact assessment, copepods, small organisms with a short life cycle, were exposed to sediment elutriates, and several end-points were measured. As a result, sediment elutriates prepared from polluted sites caused growth retardation in marine copepods. In terms of molecular biomarkers, antioxidant-related and chaperone protein gene expression levels were increased in a dose- and time-dependent manner. Thus, we suggest that sediment elutriate tests can provide an effective alternative for toxicity assessment using whole sediment samples. Further studies are required to obtain sufficient data for future applications.