• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.3
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• pp.287-295
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• 2013

The growth, respiration, ingestion, and ecological efficiencies of Hexagrammos otakii larvae and juveniles reared on different diets and temperatures were estimated. A factorial experiment using two diets [non-enriched hatched Artemia nauplii (NEA) and enriched Artemia nauplii (EA)] crossed with two temperatures [natural seawater temperature (NT, $5.1-8.5^{\circ}C$) and heated seawater (HT, $13{\pm}0.5^{\circ}C$)] was conducted to investigate growth and energy budgets of Hexagrammos otakii larvae and juveniles. The energy used by larvae and juveniles for 6 weeks was calculated using data on ingestion, growth, respiration, excretion, and egestion. In the NT trials, the energy used for growth by larvae and juveniles was 0.121 and 0.129 Kcal in the NEA and EA treatments, respectively. Assimilation efficiency at NT were 78.0% and 80.2% in the NEA and EA trials, respectively. Gross growth efficiency ($K_1$) were 60.5% and 62.3% and net growth efficiency ($K_2$) was 77.56% and 77.71% in the NEA and EA trials, respectively. In the HT trials, the energy used for growth by juveniles was 0.189 and 0.212 Kcal in the NEA and EA trials, respectively. Assimilation efficiency at HT was 86.4% and 95.1% in the NEA and EA trials, respectively. Values of $K_1$ and $K_2$ at HT were 69.5% and 80.43%, respectively, in the NEA trials, and 73.9% and 77.66%, respectively, in the EA trials. These results suggest that enriched Artemia nauplii and higher temperatures ($13{\pm}0.5^{\circ}C$) are effective for rearing larvae and juveniles of H. otakii.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.565-566
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• 2001

To investigate the food organisms of the Chasmichthys dolichognathus during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchongnam-do Sochon-gun Su-myon Dodun-ri between on early June from end of May 1998, were observed. Total length of the juveniles of C. dolichognathus was 6.5mm ∼10.0mm size, and the participation rate of feeding was 67.7％. Main food organisms were such as copepods, amphipods, shrimp larvae, polychaete larvae, and these occupied more than dry weight 2％. Copepods among them dominated the most quantitys by avergage 65.5％, and next, food organismsms appeared much by order of polychaete larvae and shrimp larvae etc. Therefore, most important food organisms of juvenile stage of C. dolichognathus were copepods, polychaete larvae, shrimp larvae etc.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.05a
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• pp.359-360
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• 2002

To investigate the food organisms of the Tridentiger trigonocephalus during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchongnam-do Sochon-gun Su-myon Dodun-ri between on early June from end if may 1999, were observed. Total length of the juveniles of T. trigonocephalus was 5.5mm∼9.0mm size, and the participation rate of feeding was 68.5%. Main food organisms were such as copepods, amphipods, shrimp larvae, polychaete larvae, and these occupied more than dry weight 2%. Copepods among them dominated the most quantitys by average 67.5%, and next, food organismsms appeared much by order of polychaete larvae and shrimp larvae etc.. Therefore, most important food organisms of juvenile stage of T. trigonocephalus were copepods, polychaete larvae, shrimp larvae etc.

• Proceedings of the Korean Aquaculture Society Conference
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• 2002.08a
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• pp.225-226
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• 2002

To investigate the food organisms of the Tridentiger trigonocephalus during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchongnam-do Sochon-gun Su-myon Dodun-ri getween on early June from end of May 1999, were observed. Total length of the juveniles of T. trigonocephalus was 5.5mm∼9.0mm size, and the participation rate of feeding was 68.5%. Main food organisms were such as copepods, shrimp larvae, polychaete larvae, and these occupied more than dry weight 2%. Copepods among them dominated the most quantitys by average 67.5%, and next, food organismsms appeared much by order of polychaete larvae and shrimp larvae etc.. Therefore, most important food organisms of juvenile stage of T. trigonocephalus were copepods, polychaete larvae, shrimp larvae etc.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.1
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• pp.29-38
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• 2005

The distributions of fish larvae and juveniles from the East China Sea, Yellow Sea and near Tsushima Island were investigated in Spring using the Maruchi (1994-1995) and Unagi (1996-1997) nets. A total of 94 species of fish larvae and juveniles belonging to 49 families under 17 orders were identified, of which Engraulis japonicus was dominant in every year except 1995 where Trachurus japonicus was dominant. Cluster analysis based on abundance and species composition by sampling stations (St.) revealed that the similar stations formed an arcuate group from Tsushima Island to southern Jeju Island in 1994, and from the Yellow Sea to southern Jeju Island in 1996. We concluded that these patterns resulted from the influence of the Tsushima Current prevailing in the east, and the Chinese Continental Waters and/or Hwanghae Cold Waters prevailing in the west, with Jeju Island exerting an influence in the centre. The diversity and composition of St. 97-3 and St. 97-5, both located where the Tsushima Current splits from the Kuroshio Current, was greatly different despite their close proximity. However, the former is located on the continental shelf, with the latter on the continental slope. This suggested that both topography and the Kuroshio Current have the most influence on the distribution of fish larvae and juveniles in this region. Furthermore, the weak Hwanghae Cold Waters of 1997 may have also limited the mixing of fish larvae and juveniles between the two stations.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.180-185
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• 2016

To investigate the feeding habits of Tridentiger trigonocephalus juveniles captured in the intertidal zone of Dodun-ri, Seocheon-gun from the end of May to early June 2012, the gut contents were observed. Feeding incidence of the juveniles increased twice a day, first in the morning and second in the afternoon. The major food organisms of the juveniles (6.5~10.0 mm NL) were composed of copepods (65.4%), amphipods (2.0%), shrimp larvae (14.5%), polychaete larvae (22.6%), and etc. These food items held more than 2 percentage in the dry weight of the total food items.

• Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.301-309
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• 2015

Chub mackerel, Scomber japonicus, larvae and juveniles were reared from hatching to 35 days after hatching (DAH), and the development of their digestive systems was histologically investigated. The larvae were initially fed on rotifers and Artemia nauplii starting around 19 DAH, and thereafter on Artemia nauplii, fish eggs, and a formulated feed mixture. The primitive digestive system differentiated at 3 DAH; the digestive tract was distinctively divided into the buccopharyngeal cavity, esophagus, stomach, air bladder, intestines, and rectum. The gastric gland and pyloric caeca first appeared at 5 and 7 DAH, respectively. The stomach was divided into cardiac, fundic, and pyloric regions in the preflexion phase. The number of gastric glands and pyloric caeca, as well as the volume of the gastric blind sac increased markedly, with development continuing into the juvenile stage. The precocious development of the digestive system during the larval period might be related to the early appearance of piscivory, which is able to support high growth potential. The organogenesis results obtained for this precocial species represent a useful tool to aid our understanding of the physiological requirements of larvae and juveniles to ensure optimal welfare and growth under aquaculture conditions, which will improve current rearing practices of this scombrid species.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.4
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• pp.396-405
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• 2017

We observed the osteological development in larvae and juveniles of Korean spotted sleeper Odontobutis interrupta bred in the laboratory in April 2014. Immediately after hatching, the prelarvae, which were about 4.27 mm long, showed ossification of the premaxillary bones in the upper jaw and the dentary and articular bones in the lower jaw. At 7.11 mm, the larvae showed complete fusion of the post-cleithra and ossification of the scapulae with the appearance of one hole. At 8.65 mm, the larvae showed ossification of seven ribs from the third abdominal vertebra and an increase in the length of the neural spine and hemal spine. The number of caudal fin rays increased to 19. At 11.9 mm, the juveniles showed ossification of three procurrent rays on the side of the parhypural bone as well as ossification of two procurrent rays on the side of the epural bone, indicating the complete ossification of all spicules.

• Proceedings of the Korean Aquaculture Society Conference
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• 2005.05a
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• pp.80-81
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• 2005

To investigate the food organisms of the Acanthogobius hasta during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchong- nam-do Sochon-gun Su-myon Dodun-ri (Fig. 1) between on early June from end of May 2003, were observed. Total length of the juveniles of A. hasta was 5.5 mm ${\sim}$ 8.9 mm size, and the participation rate of feeding was 69.6%. Main food organisms were such as copepods, decapods, polychaete larvae, amphipods and these occupied more than dry weight 3.9%. Copepods among them dominated the most quantitys by average 62.7%, and next, food organisms appeared much by order of decapods, polychaete larvae and amphipods etc.. Therefore, most important food organisms of juvenile stage of A. hasta were copepods, decapods, polychaete larvae, amphipods etc.

• Proceedings of the Korean Aquaculture Society Conference
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• 2005.05a
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• pp.82-83
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• 2005

To investigate the food organisms of the Chaenogobius mororanus during the juveniles stage, the stomach contents of fish, captured in the intertidal zone of Chungchong- nam-do Sochon-gun Su-myon Dodun-ri (Fig. 1) between on early June from end of May 2003, were observed. Total length of the juveniles of C. mororanus was 5.0 mm ${\sim}$ 8.4 mm size, and the participation rate of feeding was 71.4%. Main food organisms were such as copepods, decapods, polychaete larvae, amphipods and these occupied more than dry weight 3.9%. Copepods among them dominated the most quantitys by average 62.0%, and next, food organisms appeared much by order of decapods, polychaete larvae and amphipods etc.. Therefore, most important food organisms of juvenile stage of C. mororanus were copepods, decapods, polychaete larvae, amphipods etc.