• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.842-851
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• 1998

Development and growth of Acartia steueri from Ilkwang Bay, southeastern coast of Korea, were determined under various temperatures and food condition (Isochrysis galbana and Dunaliella salina) in the laboratory. Relationship between egg hatching time ($D_E$, day) and temperature (T, $^{\circ}C$) was $D_E=744(T+3.5)^{-1.97}$. Mean hatching success was $88.4\%$ in temperature range of $8.4\~26.2^{\circ}C$. This suggests that A. steueri may be adapted to the temperature ranges in temperate regions. Post-embryonic development pattern was equiproportional rather than isochronal, with longer stage duration of copepodites than that of the nauplii. Stage duration of NI was the shortest of all developmental stages, while the duration of NII was the longest in duration of the other nauplii. Male was morphologically distinguished from female in CIV stage, and male was developed faster than female. Median development time at a given temperature was calculated from the Belehradek equation by proper multiplication of proportional constant for embryonic development. Body carbon weight at $19.1^{\circ}C$ was increased exponentially with time. Mean specific growth rate of nauplii (0.200 $d^{-1}$), except for NI stage, was not significantly different from that of copepodites (0.190 $d^{-1}$), with the lowest rate in NVI stage (0.107 $d^{-1}$), probably due to energy consumption for metamorphosis rather than somatic growth. The results suggest that although the development pattern determined in this study was not identical with Uye's result for A. steueri (e.g. Uye, 1980b), median development time may be applicable to calculate the stage duration of A. steueri in this study area.

• Korean Journal of Ichthyology
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• v.12 no.2
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• pp.129-136
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• 2000

The aucha perch, Coreoperca kawamebari was collected in Tam-jin river from February to June 1998. It was reared in the laboratory and observed the spawning behavior and early life history. Spawning season was from mid of April to the end of May in the Tam-jin river. The fertilized eggs were demersal of adhesive, transparent and spherical in shape. Egg diameter was 2.21~2.65 mm with several oil globule of 0.058~0.343 mm. Hatching occurred about 194 hours 23 minutes after fertilization at water temperature of $18{\sim}22^{\circ}C$. Newly-hatched larvae were 5.09~5.68 mm in total length(TL, mean: 5.38mm) with 10~11+18=28~29 myotomes and opened mouth and anus. Melanophores were distributed on the eye lens, on the head, around the yolk, on the dorsal part and the abdominal region of the trunk. After hatching 5 days larvae attained 6.12~6.68 mm in TL (mean: 6.47 mm), and the yolk sac was completely absorbed and transformed to postlarva stage. The larvae reached to the juvenile stage with all the fins were formed with complete set of fin rays (D. XII-12~13; A. III-8~10; P. 11~13; V. I-4~5) at the 22 days after hatching and of the larvae was 11.54 mm in total length. In 32 days after hatching, the juvenile was 13.05 mm in TL. This period was similar to adult in body form and the spot.

• Journal of Sericultural and Entomological Science
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• v.15 no.2
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• pp.68.2-68
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• 1973

1. 오갈병은 전국에 분포하고 최근지역에 따라 3∼4배씩 매년 발생이 급증한다. 2. 마름무늬 매미충은 1년 3세대 발생하며 1세대가 5월중순-7월초순이고 2세대가 7월중순-8월중순이며 3세대는 8월하순부터 10월초까지였다. 3. 마름무늬 매미충 산란은 가지의 하부에 산란하는 것이 많다. 4. 마름무늬 매미 충 월동란은 4월 24일에 안점기에 달하고 5월 5일부터 부화 시작한다.

• Animal Systematics, Evolution and Diversity
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• v.10 no.2
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• pp.199-205
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• 1994

In the life cycle of Coryne pusilla Gaertner, a medusa is lacking and the planula larvae represent the only known dispersive stage. The planula larvae crawled on the surface of culture vessel for about 21 hours after release, and settle down and start metamprohosis.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.281-282
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• 2001

본 연구는 현재까지 국내에서 가숭어, Chelon lauvergnii의 성숙 및 인공 종묘 생산에 관한 구체적인 연구 보고는 매우 미흡한 실정임을 고려, 가숭어의 효과적인 인공 종묘 생산을 위한 기초 자료로서 산란기 특성 조사 및 부화 자어에 대한 rotifer, Artefnia, 배합사료 공급에 따른 성장과 생존을 조사하였다. 또한 rotifer와 brine shrimp, Artemia nauplius를 오징어 간유, 식물성 플랑크톤 건조 분말인 Maxima$^{TR}$ , Chlorella sp.로 각각 영양 강화한 후 치어에 공급시 자어의 성장과 생존에 대한 그 효과를 비교 분석하였다. 아울러 밀도별 사육 실험을 통한 적정 밀도를 규명하여 가숭어 종묘 생산시 효율적이고 경제적인 기술을 개발하고자 본 연구를 수행하였다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.361-362
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• 2001

어류의 초기 먹이생물로 이용되는 rotifer의 배양은 국내에서 대부분 어류종묘를 생산하는 시기는 물론이고 초기먹이생물이 불필요한 시기에도 차기의 잠재적 수요를 위하여 연중 유지되고 있다. 현재와 같은 살아 있는 상태의 rotifer를 분양 또는 공급하는 것은 계속 배양상태를 유지해야 하는 번거로움과 함께 높은 생산원가를 감수해야 하고, 또 수요가 일시에 증가하는 어류 종묘 생산기에는 적기에 필요량을 확보하기가 어려워 수요공급의 불균형을 초래한다. (중략)

• Animal Systematics, Evolution and Diversity
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• v.5 no.2
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• pp.121-137
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• 1989

The larval stages of Scopimera longidactyla reared in the laboratory are described and illustrated in detail. The larval development consists of five zoeal and a megalopal stages. At 25$^{\circ}C$, the megalopa and the first crab instar were attained in 21 and 31 days after hatching, respectively. The larvae of Scopmera can be distinguished from those of other genera in the Scopimerinae and other sumbfamilies in the Ocypodidae by the relativelength of rostral carapace spines to carapace. The larvae of S. longidactyla are similar in morphology to those of S. globosa but distingished by the differences in larval , size, and appendage setation.

• The Korean Journal of Zoology
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• v.39 no.1
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• pp.106-114
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• 1996

Zoeae of Alpheus euplirosyne rlchardsoni Valdwyne, 1971 reared in the laboratory are described and Illustrated The culture was carded out under the laboratory condition with the photoperiod l4hr light and lOhr darkness and salinity of 33.3$\textperthousand$ at 25$^{\circ}$C. This species exhibits extended development on the egg size just before hatching and on the length of the first zoea. The morphological differences between the first zoea of this species and those of five other species in the same genus are discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.4
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• pp.444-448
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• 1989

The division and circadian DNA-synthesis rtythm are studied in chick liver immediately after hatching. The vision function is tested by the mitotic and the $^3H-thymidine$ labelling index The DNA synthesis exhibited a cyclic variation of 12 hours immediately after hatching. The rhythmic changes of DNA synthesis was maintained in the liver of meal-fed chickens, but the DNA synthetic activities decreased gradually in the starved chicken liver. From this time, the rhythm of DNA synthesis was greatly afffected by lighting schedule, all these DNA synthesis of chicken liver was accompained by mitosis.

• Korean Journal of Ichthyology
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• v.3 no.1
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• pp.1-10
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• 1991

Spawning behavior and development of eggs and larvae of Mugilogobius abei were observed in the laboratory at Pusan, Korea. The adult male of Mugilogobius abei was observed making nest-like spawning-bed to lay eggs and showing territorial and courtship behaviors. The eggs were transparent and spherical in shape, measuring 0.40~0.50 mm in diameter. They have a bundle of adhesive filaments at their basal end and a cluster of small oil globules. The eggs became ellipsoid shape after the insemination and measured about 0.93~0.96 mm on the long axis. Hatching began about 110 hours after fertilization at water temperature of $24.5{\sim}25.5^{\circ}C$. The newly hatched larvae were 2.04~2.10 mm in total length, with 24~25(8~9+16) myomeres. Many melanophore and guanophore are distributed on eye cups, gas bladder, optic vesicle and the caudal region. Four days after hatching the yolk and oil-globule were completely absorbed and the larvae attained a total length 2.20~2.35 mm. The larvae swam actively in the aquarium and start to practice feeding on the rotifer. Twelve days after hatching, the larvae averaged 3.20 mm in TL and the caudal notochord flex at $45^{\circ}$. Rudimental second dorsal, anal, caudal and ventral fins are also formed. The larvae attained 10.40~10.80 mm in TL, 35 days after hatching, are found to start the bottom-life after having completely formed first dorsal and ventral fins. The larvae reached the juvenile stage at 50~60 days after hatching and attained 15.37~20.25 mm in TL. At this period all scales appeared on the body.