• 수산해양기술연구
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• 제51권2호
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• pp.221-226
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• 2015

During the study periods, total 143 individuals of Lateolabrax japonicus were collected. Body length (BL) range was 2.0-11.8 cm. Empty stomach occurred in 8.4%. The most abundant prey was copepods. Among copepods, Tigriopus japonicus was the most abundant prey appeared 32.1 in %F. Next important prey was shrimps and mysids. The results of analysis in ontogenetic changes, main prey of two small size classes (2.0-3.9 cm, 4.0-5.9 cm) were copepods. Thereafter, copepods percentage was decreased, but shrimps, mysids, fishes percentage was increased by increasing body length from 8.0 cm< size class.

• Ocean and Polar Research
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• 제36권2호
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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.

• 한국환경과학회지
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• 제20권11호
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• pp.1383-1394
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• 2011

Environmental impacts of suspended solids (SS) released in coastal area by dredging, reclamation and construction can cause serious damages to coastal habitats and benthic organisms. Acute toxicity tests (4-7 days) were conducted to identify the relationship between SS concentration and mortality of three marine benthic species; benthic copepod (Tigriopus japonicus) adult, Pacific abalone (Haliotis discus hannai) spat, and olive flounder (Paralichthys olivaceus) fry. Benthic copepod was the most sensitive to SS followed by olive flounder fry and Pacific abalone spat, with an $LC_{50}$ (lethal concentration of 50% mortality) value of 61.0 mg/L and LOEC (lowest observed effective concentration) value of 31.3 mg/L for benthic copepod. LOEC and 7 day-$LC_{50}$ for Pacific abalone spat were 500.0 mg/L and 1887.7 mg/L, and those for olive flounder fry were 125.0 mg/L and 156.9 mg/L, respectively. The tolerance limits of the test species to SS revealed the various concentration ranges of SS, which reflects the physiology and ecology of the test species. These results are very valuable for the determination of SS concentration of effluents released into the coastal area by dredging, reclamation and construction etc. Also, sharp increase of SS can cause long-term damages to the benthic and sessile fauna by blanketing of benthic substratum. These experimental procedures for marine bioassay and acute toxicity results can be a useful guideline for practical management planning of SS discharge into coastal area.

• 한국어류학회지
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• 제28권4호
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• pp.267-272
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• 2016

채집기간 동안 총 315개체의 점망둑 (Chaenogobius annularis)이 채집되었으며, 8.6%의 공복률을 보였다. 점망둑의 가장 중요한 먹이생물은 상대중요성지수비 50.5%를 차지한 요각류(Copepoda)였다. 요각류 다음으로 해조류(Seaweed)가 우점하였으며, 그 외 곤쟁이류(Mysidacea), 만각류(Cirripedia), 단각류(Amphipoda) 등도 섭식하였으나 그 양은 많지 않았다. 점망둑은 성장함에 따라 요각류의 섭식은 감소하였고 해조류의 섭식이 증가하였다.

• Molecules and Cells
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• 제22권3호
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• pp.314-322
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• 2006

The whole mitochondrial genome (14,915 nt) of Pollicipes mitella (Crustacea, Maxillopoda, Cirripedia, Thoracica) was sequenced and characterized. It is the shortest of the 31 completely sequenced crustacean mitochondrial genomes, with the exception of a copepod Tigriopus japonicus (14,628 nt). It consists of the usual 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 relatively short non-coding region (294 nt). The thoracican cirripeds apart from Megabalanus volcano have the same arrangement of protein-coding genes as Limulus polypemus, but there are frequent tRNA gene translocations (at least 8). Some interesting translocation features that may be specific to the thoracican cirriped lineage are as follows: 1) trnK-trnQ lies between the control region and trnI, 2) trnA-trnE lies between trnN and trnS1, 3) trnP lies between ND4L and trnT, and 4) trnY-trnC lies between trnS2 and ND1. In P. mitella there are two trnL genes (L1 and L2) in the typical crustacean positions (ND1-L1-LrRNA and CO1-L2-CO2). The present result is compared and discussed with the other three cirriped mitochondrial genomes from one pedunculate (Pollicipes polymerus) and two sessiles (Tetraclita japonica and M. volcano) published so far. Mitochondrial protein phylogenies reconstructed by the BI and ML algorithms show that the thoracican Cirripedia is monophyletic (BPP 100/BP 100) and associated with Remipedia (BPP 98/BP 35). In addition, Oligostraca, including Ostracoda, Branchiura, and Pentastomida, is a monophyletic group (BPP 99/BP 68), and is basal to all the other examined arthropods. Remipedia + Cirripedia appears as an independent lineage within Arthropoda, apart from Thoracopoda (Malacostraca, Branchiopda, and Cephalocarida). The Thoracopoda is paraphyletic to Hexapoda. The present result suggests that the monophylies of Crustacea and Maxillopoda should be reconsidered.

• 한국양식학회지
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• 제18권1호
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• pp.13-18
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• 2005

고부가가치 양식 대상종이고, 자원조성용으로 효과적인 돌돔의 안정된 종묘생산을 위한 연구의 일환으로서 수온, 먹이종류에 따른 성장과 생존 및 물 만들기를 실시하여 대량 종묘생산의 효과를 조사하였다. 자연해수 실험구($20.5^{\circ}C$)와 가온해수 실험구($25.3^{\circ}C$)조건에서 30일 동안 사육한 결과 가온구가 대조구 보다 2배정도 빠른 성장을 보여 유의차가 인정되었다. 생존율은 가온구에서 부화 후 30일까지 평균 $24.0\%$였고, 대조구에서는 $12.3\%$로서 상대적으로 낮았다. 먹이계열에 따른 자치어의 사육실험 결과 로티퍼와 배합사료를 공급한 실험구에서는 먹이효율이 낮았으나, 사육수조에 Nannochloropsis oculata 첨가하고, 로티퍼, 알테미아, 코페포다 및 배합사료를 혼합 공급한 실험구에서 성장 및 생존율에서 양호한 결과를 보여 유의한 차이가 인정되었다. 대량종묘생산 결과 일령 50일까지 생존율은 평균 $22.5\%$였으며, 치어의 평균 전장은 62.0$\pm$4.0mm로 성장하였다. 그리고 돌돔자어의 로티퍼 1회 섭식량은 부화 5일째평균 10.3개체, 10일째 16.5개체, 20일째 65.5개체로서 자어의 성장과 함께 섭식량은 급격히 증가하였다.