• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.323-328
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• 1982

Kareius bicoloratus (Basilewsky) is one of the commonly found right-eye flounders and widely distributed in the coastal waters of Korea and Japan. On December 11,1980, the ailthors carried out an experiment to obtain a large number of fertilized eggs from wild adult fish caught by a trawler. The fish were obtained from Maisaka fish market, Shizuoka Prefecture, Japan. The egg is pelagic, spherical in shape and measuring 1.014-1.04 mm in diameter. The yolk as well as the egg capsule is colorless and transparent, and contain no oil globules. The hatching took place in 73 hr 45 min after fertilization at the water temperature $8.0-9.5^{\circ}C$. Newly hatched larvae are 3.09-3.146 mm in total length, with the anus situated in the middle of the body. The marginal fin does not have Pigment cells and myotome number is 17+20=37. Within one day after hatching, the larvae attained 3.77 mm in total length, and there appeared three or four melanophore on yolk sac. When the larvae attained 3.96 mm in total length, melanophores began to appear on the eye ball. Two days after hatching, the larvae attained 4.05 mm in total length, most of yolk material was absorbed, and the caudal fin began to grow at the terminal part of the notochord. When the larvae attained 4.21 mm in total length, mouth and eyes began to move. After 3 days, the larvae attained 4.342-4.394 mm in total length, alimentary canal differentiated, melanophores appeared on the lower jaw and posterior part of the fin membrane. When the larvae attaind 4.576 mm in total length, marginal line of dorsal fin membrane became concave.

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.247-252
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• 2009

The egg development and early life history of the Korean endangered fish Koreocobitis naktongensis (Cobitidae) were investigated. Eggs from the females were obtained by injecting 10 IU/g of human chorionic gonadotropin and inseminated with sperm by the dry method in the laboratory. The fertilized eggs were 1.0~1.2 mm in diameter and had no oil globules. The embryo began to hatch about 38 hrs after fertilization under water temperature of $20{\pm}1^{\circ}C$. The newly-hatched larvae were 2.6~2.8 mm in total length, and their mouth and anus were not yet opened. Seven days after hatching, the postlarvae were 4.5~5.2 mm in total length, and their yolk sacs were completely absorbed. They entered the juvenile stage when all fin-rays were formed at 50 days after hatching, and their total lengths were 21~27 mm.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.5
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• pp.465-476
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• 1993

Rockfish, Sebastes inermis is a ovoviviparous fish distributed around the coastal waters of Korea and Japan. Naturally beared larvae obtained from female fish kept in the aquarium were reared for three months in the laboratory. The naturally healed larvae were 6.05mm in average total length(TL) with $8+18{\sim}19=26{\sim}27$ myomeres. Melanophores were distributed on the top of head, around the intestine tube and on the dorsal and ventral margins of the tail, but none on the pectoral fins. The larva(7.1mm in TL) consumed all the yolk and oil globule, in 7 days after bearing, and jaw bones were more rapidly ossified than vertebrae and cranium. In 21 days after bearing, the larvae averaged 8.50mm in TL and the caudal notochord flex $45^{\circ}$. Fin development in S. inermis larvae proceeds in the following sequence: caudal, pectoral, dorsal, anal and ventral fin. Individuals $17.6{\sim}20.8mm$ in TL($65{\sim}69$ days after bearing) are regarded as the juvenile stage. All fins bones was nearly completed in this stage.

• Development and Reproduction
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• v.20 no.2
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• pp.109-118
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• 2016

This study monitored the morphological development of embryo, larvae and juvenile yellowtail kingfish, Seriola lalandi, for their aquaculture. The fertilized eggs obtained by natural spawning were spherical shape and buoyant. Fertilized eggs were transparent and had one oil globule in the yolk, with an egg diameter of $1.35{\pm}0.04mm$ and an oil globule diameter of $0.32{\pm}0.02mm$. The fertilized eggs hatched 67-75 h after fertilization in water at $20{\pm}0.5^{\circ}C$. The total length (TL) of the hatched larvae was $3.62{\pm}0.16mm$. During hatching, the larvae, with their mouth and anus not yet opened. The yolk was completely absorbed 3 days after hatching (DAH), while the TL of post-larvae was $4.72{\pm}0.07mm$. At 40 DAH, the juveniles had grown to $30.44{\pm}4.07mm$ in TL, body depth increased, the body color changed to a black, yellow, and light gray-blue color, and 3-4 vertical stripes appeared. At 45 DAH, the juveniles were $38.67{\pm}5.65mm$ in TL and $10.10{\pm}0.94mm$ in body depth. The fish were green with a light orange color, with 7 faint green-brown stripes on the sides of their body. At 87 DAH, the juveniles had grown to 236.11 mm in TL, 217.68 mm in fork length, and 136.5 g in weight. The fish resembled their adult form, with a light yellow-green body color, loss of the pattern on the sides of their body, and a yellow coloration at the tip of the caudal fin.

• Korean Journal of Ichthyology
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• v.4 no.2
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• pp.31-43
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• 1992

The blenniid fish, Entomacrodus stellifer light(Herre) is distributed in the coastal waters of southern Japan and south-eastern Korea. Matured adults of blenniid fish were collected from the rocky shore of Namchun-dong, Nam-gu, Pusan, Korea in July, 1991. The observations were made on the morphology and skeletal development of the reared larvae and juveniles. The lavae reached 5.80mm in mean total length(MTL) in 10 days after hatching. A this time the larvae have absorbed the yolk completely and became postlarvae. Melanophores are distributed on the fin membrane of the lower part of pectoral fin and ventral margins of tail. The larvae averaged 6.20mm in TL and the caudal notochord flex at $45^{\circ}$ in 13 days after hatching. The part of the fin-fold of the future dorsal and anal fins became high. The lavae reached juvenile stage in 31 days after hatching and attained 15.80mm in MTL, and all fin-rays was formed. Ossification of the cranium took place at 6.20mm of MTL(11 days after hatching) in parasphenoid. Vertebrae began to develop from the anterior end to ossify posteriorly. Ossification of all bones nearly completed when the larvae reached to 15.80mm in MTL (31 days after hatching).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.2
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• pp.203-208
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• 2020

This study was carried out to clarify the larvae and juveniles of egg development and autonomous development of Hemibarbus longirostris from Korea, and to obtain basic data for species conservation and seed production. The shape of the egg was circular and sticky. The average size of the eggs was 2.01 mm (n=10). At 185 hours after fertilization, more than 50% of the total embryos were hatched. The newly hatched larvae had an average total length of 8.10 mm (n=5) and had egg yolk in the abdomen. At 3 days after hatching, the larvae absorbed all egg yolk was average total length 8.64 mm. On the 6 days after hatching, the caudal tip of the notochord started to curve upwards was average total length 10.9 mm. At 70 days after hatching, the average total length 37.9 mm. The number of fins was i 8-10 in dorsal fin, iii 7 in the anal fin, and ii 5 in the ventral fin.

• Korean Journal of Ichthyology
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• v.26 no.4
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• pp.349-354
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• 2014

The diet composition of bullet mackerel, Auxis rochei was studied using 200 specimens collected from December 2013 to May 2014 in the coastal waters of Iloilo, Philippines. The size of A. rochei ranged from 11.1 to 31.2 cm in fork length (FL). A. rochei was epipelagic feeder that consumed mainly fishes. In addition, A. rochei consumed shrimps, copepods, crab larvae, amphipods and cephalopods. The diet also included small quantities of stomatopods, bivalves, and ostracods. Also, analysis of the prey-specific abundance against the frequency of occurrence shows that A. rochei have a narrow food niche, and are specialized feeder with fish as their dominant prey. Although fishes were the primary in food consumed by all size class. The fishes gradually increased with body size.

• Fisheries and Aquatic Sciences
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• v.8 no.4
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• pp.235-242
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• 2005

Baker's yeast, Saccharomyces cerevisiae, has been widely used as a food organism for rotifers used in the larval production of marine fish. However, the nutritional value of the yeast is relatively poor compared with that of the marine alga Chlorella. We examined the nutritional value of another yeast, Candida utilis, and whether its food value could be increased through manipulation such as a cell wall treatment. Candida utilis and S. cerevisiae and their manipulated varieties were assessed with regard to the growth and nutrition of the rotifer Brachianus plicatilis. Larvae of the flounder Paralichthys alivaceus were cultured with rotifers fed on the yeast species, and the dietary value of the rotifers for the larvae was examined. Rotifers that were fed C. utilis grew faster than those provided with S. cerevisiae. Rotifers grew slightly faster on manipulated yeast than on non-manipulated yeast varieties. Of the two yeast species, C. utilis had better dietary value for rotifers. Flounder larvae cultured with rotifers that had fed on C. utilis displayed better growth and survival ($\%$) than did those cultured with rotifers that had fed on S. cerevisiae. Although the manipulated variety of C. utilis was better than the non-manipulated variety in terms of rotifer growth, the flounder larvae survived ($\%$) and grew better when they were fed rotifers that had eaten non-manipulated C. utilis. However, the nutritional value of this yeast species was still lower than that of Chlorella.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.682-687
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• 2018

This study investigated the food value of Paracyclopina nana for flounder Paralichthys olivaceus larvae in two feeding stages, rotifer (for 12 days) and Artemia (for 16 days). In the rotifer feeding stage, survival and growth of flounder larvae in the only P. nana (nauplii) feeding experiment were higher than in the only rotifer feeding experiment on 12 DAH (days after hatching). In the Artemia feeding stage, the growth of flounder larvae in the only P. nana (C4-adult) feeding experiment and mixture feeding experiment (P. nana+Artemia) were higher than in other experiments on 30 DAH, but the survival of flounder larvae did not differ significantly among experiments. The n-3 HUFA contents of nauplius and C4-adult were 4.0% and 5.4%, respectively. Overall the results of this study indicate that the brackish water cyclopoid copepod, P. nana, is an effective live food organism for larval seedling production of marine fish.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.862-867
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• 2013

Since the industrial revolution, seawater has increased in temperature and acidity due to the increase in anthropogenic carbon dioxide in the atmosphere. To understand the effect of elevated $CO_2$ on the early life stages of fish, we reared fertilized eggs of black sea bream Acanthopagrus schlegelii under three $CO_2$ concentrations (400, 850 and 1550 ppm) for 3 weeks. The standard length and wet weight of black sea bream larvae declined with enhanced $CO_2$ concentration in the rearing water (P<0.05). However, chemical analysis using ICP-OES on internal tissues of black sea bream larvae indicated that the whole-body calcium concentration increased with $CO_2$ concentration in the rearing water. These conflicting results suggest that future experiments should examine the acid-base balance to investigate the formation of bone and otolith during larval growth.