• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.666-671
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• 2001

To investigate the food organisms and feeding selectivity of slimy (Leiognathus nuchalis) during the postlarval stage, the gut contents of the fish, captured in Kwangrang Bay in 1995, were observed. The food organisms in the gut were composed of copepod egg and nauplius, Tintinnopsis spp. and Codonellopsis sp. The indices of relative importance (IRI) indicated that Tintinnopsis spp. was the most dominant food item ($80.6\%$), and copepod nauplius was the next ($18.5\%$). Tintinnopsis spp. was the most favorite food item: it occupied $73.8\%$ of gut contents, though it did $39.2\%$ of microzooplankton in the surrounded water. The composition of copepod nauplius was higher in the larvae shorter than 2.0 mm NL. As slimy larvae grew, the size of food organisms in the gut was not changed, and their number increased, and the selectivity for food items increased.

• Korean Journal of Ecology and Environment
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• v.41 no.1
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• pp.104-110
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• 2008

The egg development and early life history of Korean endangered natural monument fish, Iksookimia choii, were investigated in 2006. The eggs from the females were obtained by injecting 10 IU $g^{-1}$ of human chorionic gonadotropin and inseminated by wet method in the laboratory. The fertilized eggs were $1.1\sim1.3mm$ in diameter and had no oil globules. Hatching of the embryo began about 24 hrs after fertilization under water temperature of $25^{\circ}C$. The newly-hatched larvae were $2.5\sim2.7mm$ in total length (TL), and their mouth and anus were not yet opened. Six days after hatching, the postlarvae were $4.7\sim5.4mm$ TL, and tip of the caudal notochord was flexed $45^{\circ}$ upward. The juveniles stage was reached when all fin-rays were formed at 35 days after hatching, and their total length were $20\sim22mm$.

• Korean Journal of Ichthyology
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• v.34 no.1
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• pp.16-24
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• 2022

The eggs development and early life history of Sarcocheilichthys variegatus wakiyae was investigated. The adult fishes were collected in Yeongsangang River, Damyang-gun, Jeollanam-do, Korea, and their spawning inducement was carried by sex maturation hormone (Ovaprim) injections. Spawning amount was mean 31±3.5 Mature eggs were cicular in shape and mean 2.40±0.05 mm in diameter. Hatching period of the embryo was 230 to 240 hours after fertilization under water temperature of 22℃. The newly hatched larvae were 10.7±0.19 mm in total length (TL). 3 days after hatching, postlarvae was measured 12.0±0.13 mm in TL and the tip of the caudal fin was bent at 45°. 11 days after hatching, it was measured 14.6±0.13 mm in TL, and transferred to juvenile as the number of fins (iii7 dorsal fin, iii6 anal fin, i7 ventral fins) reached a constant number of each part.

• Journal of Aquaculture
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• v.21 no.4
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• pp.339-345
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• 2008

Farming of the fleshy shrimp Fenneropenaeus chinensis which is a major cultured species in the west coast of South Korea, has been suffered :trom mass mortality due to disease epizootics including viruses. Since the Pacific white shrimp Litopenaeus vannamei was introduced to Korea in 2003, farming of this species has rapidly increased for years, occupying 62.5% of total cultured shrimp production in 2007. However the studies on L. vannamei culture methods for shrimp farming situations in Korea are very limited. Nursery culture of shrimp larvae has some advantages including increased survival, improved feed efficiencies, enhanced growth performance and reduced grow-out period. In this study, L. vannamei postlarvae (${PL_3}-{PL_{10}}$) with a density of $3,750-9,090/m^3$ were cultured in four raceways under limited water exchange condition for 35 days. Survival was the highest (93.6%) in tank stocked with $4,090/m^3$ and was the lowest in tank with $9,090/m^3$ (58.1 %). Mean body weight at harvest ranged from 0.071 to 0.108 g, and FCR was 0.59-0.70 in all tanks. Concentration of total ammonia nitrogen was increased up to 20 ppm on day 10 in all tanks and thereafter gradually decreased by the third week of culture. Nitrite-nitrogen was rapidly increased from the third week, representing bio-floc condition by developed nitrifying bacterial community. Of the present nursery system some modification of structure and consideration for commercial scale are needed in order to be implemented to shrimp farmers.

• Korean Journal of Ichthyology
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• v.13 no.3
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• pp.166-172
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• 2001

Parental care of eggs of Chromis fumea (Tanaka) was observed by Skin Scuba gear in August 1995 off Cheju Island. The eggs and larval development were observed in the laboratory at Pukyong National University, Pusan. Eggs were deposited on a flat surface of hard substratum and formed a plain sheet of one layer of eggs. Males showed parental care of the eggs by hovering over the nest and attacking other fishes that approached the nest. The spawned eggs were transparent, elliptical in shape and measured 0.73~0.88 mm in long axis and 0.50~0.56 mm in short axis. An analysis by T-test of the long axis of the egg with time showed a significant difference (p<0.01). However, there was no significant difference in short axis with time. Eggs were reared at water temperatures of $23.0{\sim}25.5^{\circ}C$ and took about 4~5 days from embryonic body stage to hatching. The newly hatched larvae were 1.10~1.61 mm in notochord length (NL) had 21 myomeres, has closed mouth but open anus, preanus length was 45.8% of NL. Melanophores were distributed on the occipital region of head, the eye, the peritoneal region, and along the ventral contour. The larvae absorbed the yolk material and oil globule in 3~4 days after hatching and became postlarvae. On the third day after hatching, the larvae had attained 1.9~2.4 mm in NL, had 25 myomeres, and showed rapid growth. By the ninth day after hatching, the larvae had attained 2.9 mm in NL, had an swimbladder in the dorsal margin of ventral region, the preanus length was 37.9% of NL, and their melanophores were enlarged and reduced in number.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.63-70
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• 2015

This research is about spawning behavior and morphological development of the eggs and larvae of fringed blenny which lives in Korean sea. It helps to find out the relation between fringed blenny larvae and other stichaeidae larva. Moreover, it is going to use for the basic data of taxonomical research. There were 8 mother fishes (total length 31.8~34.0 cm, average $32.9{\pm}0.21cm$), which were captured from the cost of Sindeok-dong, Yeosu-si, Jeollanam-do from December, 2010. we used trap to capture them. Mother fishes were brought to glass aquarium ($50{\times}30{\times}35cm$) and nurtured with recirculate rearing system. Breeding water temperature was $12.3{\sim}15.8^{\circ}C$ (average $14.1{\pm}2.47$) and salinity was 32.5~33.5‰ (average $33.0{\pm}0.05$‰). fertilized egg was round, opaque demersal egg. The size was 1.81~2.19 mm (average $2.00{\pm}0.27mm$, n=50). Incubation was begun after 271 hours and 30 minutes from fertilization. It started with piercing the egg membrane. prelarvae had length of 8.45~8.84 mm (average $8.65{\pm}0.28mm$, n=5) right after the incubation, and both mouth and anus were opened. After 11 days from the incubation, postlarvae had length of 10.5~11.3 mm (average $10.9{\pm}0.57mm$), and the number of myotomes was increased to 66.

• Development and Reproduction
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• v.10 no.1
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• pp.41-45
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• 2006

The spawning behavior of Liobagrus obesus was observed at Kumgang river, Yeongdong-gun, Chungcheongbuk-do from Apirl to July 2004. The fertilized eggs collected by dip net and skimming net were carried to the laboratory of Chonnam National University, and then egg, larvae and juvenils development were studied. Hatching of the embryo began about at 225 hrs 15 mins after morula stage in water temperature of $19.5{\sim}24.9^{\circ}C$(mean $22.8^{\circ}C$). The newly-hatched larvae were $7.30{\sim}7.90mm$(mean 7.66mm) in total length (TL), their mouth and anus were already opened with 14+28=42 myotomes. Sixteen days after hatching, the postlarvae were $13.00{\sim}14.05mm$(mean 13.48mm) TL, the yolk sac was completely absorbed. The juvenile stage was reached when all fin-rays were formed at 24 days after hatching, and $15.31{\sim}17.20mm$(mean 16.31mm) TL.

• Development and Reproduction
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• v.10 no.1
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• pp.47-54
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• 2006

The Tridentiger obscurus were collected of Ocheon-dong and Dolsan-do in Yeosu from Apirl to July 2003, and were carried to the laboratory to investigate their development of spawning habit, egg development, larvae and juveniles. The fertilized eggs were measured $0.86{\sim}1.07{\times}0.53{\sim}0.74\;mm$ in diameter. Hatching of the embryo began about 154 hrs 40 mins after fertilization in water temperature of $18.4{\sim}23.2^{\circ}C$(mean $21.2^{\circ}C$). The newly-hatched larvae were $2.72{\sim}2.87mm$(mean 2.83mm) in total length (TL), their mouth and anus were opened, and the yolk sac was completely absorbed. At 21 days after hatching, the postlarvae were $5.32{\sim}7.23mm$(mean 6.02mm) TL, and the tip of the caudal notochord was flexed $45^{\circ}$ upward. The juveniles stage was reached when all fin-rays were formed at 45 day after hatching, and $11.62{\sim}14.32mm$(mean 13.45mm) TL.

• Korean Journal of Ichthyology
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• v.5 no.2
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• pp.151-159
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• 1993

Greeling, Hexagrammos otakii Jordan et Starks is commonly found at the coastal waters of Korea and Japan. The authors carried out the artificial insemination in the laboratory on Dec, 17, 1987, and reared the hatched larvae in an aquarium. The eggs were demersal and adhesive, and their diameters were 2.00~2.15mm. Color of yolk was light yellow in the early stage, and then turned to orange before hatching. The yolk had numerous tiny oil globules. Hatching began about 477hours after insemination under water temperature of $10.0{\sim}14.5^{\circ}C$. The newly hatched larvae were elongate in shape and 7.48~8.25mm in total length(TL) with 49~50 myomeres. The larvae absorbed the yolk material and oil globules completely in 5days after hatching and became postlarvae. In 17days after hatching, mean total length of the larvae was 9.85mm, and the caudal notochord flex at $45^{\circ}$. In 23days, total length reached 10.54mm. The part of the fin-fold of the future dorsal and anal fins became high. Spawning season of the Greenling is known to be from November to January in the southern coast of Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.3
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• pp.129-137
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• 1989

Sand fish, Arctoscopus japonicus (Steindachner) is distributed in the coastal waters of East Sea of Korea, Japan, and Alaska. On December 1, 1987, matured adult of sand fish were collected from the shore of Ok-kye, Myongju-gun, Kangwon-do, Korea. The authors carried out artificial insemination on boat. The fertilized eggs were incubated and the larvae were reared in laborato교. The eggs of this species were demersal and adhesive, and their diameter were varied within $3.1\~3.4$mm (mean 3.3 mm, n= 10). They have a number of small oil globules. The spawned eggs in nature were formed the egg mass which were measured ca. 4 m in dia-meter. The hatching took place in 65 days after fertilization at the water temperature of $8.7\~12.3^{\circ}C$. The newly hatched larvae were $8.5\~10.2$ mm in total length with 11 (abdominal) +40 (caudal) = 51 myomeres. 24 days after hatching, the larva attained 19.4 mm in total length, at this time the larvae absorbed the yolk completely, and become postlarvae. 32 days after hatching, the larva attained 23.4 mm in total length, and become juvenile. 56 days after hatching, the juvenile reached 29.9 mm in total length and had adult form. 5 spines of preopercle bone were formed at 24.4 mm in total length. At ca. 15 mm in total length, the form of the pectoral fin was transformed into the adult form.