• 한국어류학회지
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• 제34권1호
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• pp.25-33
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• 2022

대륙종개의 난발생 및 초기생활사 연구를 위해 2020년 4월 26일 북한강 지류인 상천천에서 대륙종개를 채집하였다. 성숙한 암컷과 수컷의 복강에 HCG 10 IU/g를 주사하였고 15시간 후에 건식법으로 인공수정하였다. 대륙종개 암컷 전장 70.64~79.24 mm (n=3)의 포란수는 1,308±293개였고, 성숙란은 황회색의 침성점착란이었다. 수정란의 난경은 1.13±0.01 mm (n=10)였고 수정 후 104시간 만에 부화하였다. 난발생 시 수온 15℃ 그룹의 부화율은 평균 80.1±1.2%로 나타났고, 수온 20℃ 그룹은 61.5±6.8%로 나타나 발생 수온은 15℃에서 적합하였다 (p<0.05). 부화 직후의 자어는 전장 3.12±0.06 mm (n=10)였으며 몸은 투명하였다. 부화 후 4일에는 전장 4.89±0.09 mm (n=10)로 입과 항문이 열리면서 먹이활동을 시작하였고 난황이 모두 흡수되면서 전기자어기로 이행하였다. 부화 후 14일에는 전장 8.66±0.14 mm (n=10)로 척색말단이 위로 휘어지기 시작해 중기자어기로 이행하였고 부화 후 21일에는 전장 10.98±0.40 mm (n=10)로 척색말단이 45°로 완전히 휘어졌다. 부화 후 26일에는 전장 13.47±0.37 mm (n=10)로 모든 지느러미 기조가 정수가 되어 치어기로 이행하였다.

• 한국어류학회지
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• 제34권2호
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• pp.86-95
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• 2022

줄가자미의 난발생 및 자치어 형태발달을 관찰하여 종자생산 및 분류학적 연구의 기초자료로 이용하고자 한다. 2017~2018년까지 동해안에서 어미를 채집하여 원형수조(Ø 6 ×1 m) 수온 12.8±1.9℃에서 사육하였다. 수정란의 크기는 1.42~1.59 mm (평균±SD, 1.51±0.04 mm, n=50)였고, 난의 형태는 구형의 무색 투명한 분리부성란이었다. 난발생 과정은 수정 60분 후 난황과 난막이 분리되었고, 62시간 후 배체가 형성되었다. 수정 144시간 후 전체의 50% 이상이 부화가 완료되었다. 부화 직후의 자어는 전장 4.22~4.64 mm (4.53±0.16 mm, n=10)로 입과 항문은 열리지 않았고, 부화 후 10일째 전기자어는 전장 5.88~6.62 mm (6.31±0.33 mm, n=10)로 난황 흡수가 완료되고, 입이 열리기 시작하였다. 부화 후 55일째 중기자어는 전장 10.4~13.3 mm (12.7±1.3 mm, n=10)로 척추말단 끝부분은 휘어졌다. 부화 후 120일째는 전장 35.3~40.5 mm (39.5±2.4 mm, n=10)였고, 각 지느러미 기조 수는 등지느러미 79~94개, 뒷지느러미 63~75개로 정수에 달하면서 치어기로 이행하였다.

• 한국발생생물학회지:발생과생식
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• 제24권1호
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• pp.63-70
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• 2020

This study aimed to investigate early life of Coreoperca herzi living in Han River and compare morphological differences between different groups during the development in order to provide basic data for relevant taxonomic research. On average, one female individual spawned 541 to 861 eggs (average 701) at once. After 259 hours, the tail broke out of the egg membrane and hatching began. Immediately after hatching, the larvae were average 7.81±0.10 mm (n=5) in total length. 60 days the juvenile was average 35.9±1.30 mm (n=5) in total length. The white spots spread to the rest of the body, rending the same pattern as that on the body of their broodstock fish.

• 한국어병학회지
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• 제26권1호
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• pp.11-17
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• 2013

The cadmium (Cd) toxicological effects on the fertilized eggs, embryos and larvae were investigated in olive flounder, Paralichthys olivaceus water-borne exposed to Cd. The survival rate and hatching success of the embryos significantly diminished in treated groups in dependence of the Cd concentration. Significant differences were found at ${\geq}30{\mu}g\;L^{-1}$ exposed groups compared to the control group. A significant increase of malformation of the embryo was observed at ${\geq}20{\mu}g\;L^{-1}$ exposed groups. They usually include such symptoms as clouded yolk-sac abnormality, fin erosion and spinal curvature. A significant reduction in the survival rate of the larvae was observed in ${\geq}20{\mu}g\;L^{-1}$ exposed groups with accompanied by the disorder. Notably, in larvae, a concentration as low as $10{\mu}g\;L^{-1}$ exposed groups caused significant elevated abnormalities that is incidences of spinal cord deformation, abnormal eyes, deformation of the head region and severe developmental delay.

• Animal Systematics, Evolution and Diversity
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• 제7권2호
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• pp.189-194
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• 1991

전라북도 임실군 신평면과 관촌면 일대의 섬진강 수계에서 채집한 납자루속 어류의 표본을 조사한 바 기존의 것과 다른 종이 발견되어 신종 Acheilognath-us somjinensis로 기재화고 한국명으로는 임실납자루로 명명한다. 본 신종은 유사종인 Acheilognathus koreensis에 비해 산란시 암컷의 산란관 길이가 훨씬 길고 난의 형태가 둥글며 초기 발생과정도 현저한 차이가. 또한 유사 종간의 인공 교잡시 발생이 중지되어 주목되었다.

• 한국수산과학회지
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• 제54권2호
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• pp.170-179
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• 2021

This study was conducted to identify taxonomic differences in the characteristics of Acheilognathus majusculus and A. yamatsutae during their initial life history via an interspecific hybridization experiment. Hatching time required 36 h for MY and 49 h for YM at 21.5℃, showing a significant difference of 13 h between the hybrids. The hatching rates of the cross-bred eggs were 30% for cross MY (A. majusculus♀×A. yamatsutae♂) and 40% for cross YM (A. yamatsutae♀×A. majusculus♂). The hatching larvae size was total length 3.13-3.43 mm in MY and total length 3.89-4.22 mm in YM, which was larger in YM. The hybridization test between A. yamatsutae and A. majusculus that live in the same water stream confirmed that no interspecific reproductive isolation occurred.

• 한국수산과학회지
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• 제56권4호
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• pp.549-557
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• 2023

This study aimed to investigate taxonomic differences in the early life history characteristics of Rhodeus ocellatus and Rhodeus notatus through an interspecific hybridization experiment. The hatching rates of the cross-bred eggs were 50% for the ON cross (R. ocellatus ♀×R. notatus♂) and 67% for the NO cross (R. notatus♀×R. ocellatus♂). Interestingly, the hatching time of the hybrids was longer than that of their parents. The newly hatched larvae exhibited distinct differences in their physical characteristics. The head of the adult fish protruded forward more than that of the ON cross. The pterygoid process was 45° for the ON cross and 90° for the NO cross. Furthermore, the tail shape of the ON and NO crosses closely resembled that of R. notatus.

• Parasites, Hosts and Diseases
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• 제56권5호
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• pp.501-507
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• 2018

We described here the morphological characteristics for the species identification and fish hosts of Isoparorchis sp. (Digenea: Isoparorchiidae) in the Republic of Korea (Korea). Total 1,371 freshwater fishes collected in Yangcheon (Stream) in Sancheong-gun, Gyeongsangnam-do were examined by the artificial digestion methods to survey the infection status of digenetic trematode metacercariae for 4 years (2013-2016). Adult and larval worms of Isoparorchis sp. were detected in 38 (8.4%) out of 451 fish in 4 species, i.e., Pungtungia herzi, Acheilognathus koreensis, Squalidus japonicus coreanus and Odontobutis platycephala, examined. The infection density was 1.1 worm per fish infected. They were mainly found in the subcutaneous tissues and abdominal cavities. Nodules with worms in the subcutaneous tissues were revealed as the blue ink-colored bulges. Adults leaf-like, $21.6{\times}9.84mm$ in average size. The ratio of body length to body width was 2.20: 1. Oral sucker subterminal, $1.03{\times}1.22mm$. Pharynx muscular, $0.55{\times}0.54mm$. Esophagus very short. Ceca convoluted, terminated near the posterior end. Ventral sucker anterior 1/3.75, $1.99{\times}2.10mm$. The ratio of ventral sucker to oral sucker was 1.74: 1. Testes round to elliptical, both sides of ventral sucker, $1.43{\times}1.33mm$. Vitellaria highly dendritic, posterior 1/3 level. Eggs operculated, embryonated, $52{\times}32{\mu}m$ in size. By the present study, 4 fish species aforementioned are to be listed as the fish hosts of Isoparorchis sp. in Korea and additionally the morphological characteristics are to be described for the species identification.

• Fisheries and Aquatic Sciences
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• 제4권4호
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• pp.208-218
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• 2001

We have investigated the gonad index (GI), gonadal development, reproductive cycle, first sexual maturity, sex ratio, the number of spawned eggs and spawning frequency of the Manila clam, Ruditapes philippinarum. Samples were collected from the intertidal zone of Komso Bay, Korea from January to December in 1999. Monthly changes in the gonad index (GI) and condition index showed a similar pattern in the reproductive cycle. The spawning period was once a year between early June and early October, there was a spawning peak between July and August when seawater temperature was over $20^{\circ}C$. The reproductive cycle of this species can be categorized into five successive stages; early active (February to March), late active (April to May), ripe (April to August), partially spawned (June to October), and spent/inactive stage (August to March). Percentages of first sexual maturity of female and male clams of l5.1-20.0mm in shell length were $56.3\%$ and $60.0\%$, respectively, and $100\%$ for the clams >25. mm. The sex ratio of individuals >15.1 mm in shell length was about 1:1 $(\chi^2= 0.02,\;p>0.05)$. Number of the eggs released from each clam by the induction increased as the size of clam in terms of shell length increased. Mean number of the eggs from the second induction of the spawning was $75.35-84.30\%$ $(average\;79.81\%)$ of the number of the eggs released in the first spawning. Our data indicated that R. philippinarum in Komso Bay has one major spawning peak with over two minor spawning, and the interval of each spawning was estimated to be approximately 15-17 (average 16.5) days.

• Journal of Nutrition and Health
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• 제31권2호
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• pp.206-212
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• 1998

This study was undertaken to analyze the iodine content in commonly donsumed Korean foods. Food samples were purchased from 3 randomly selected markets. The iodine contents in foods were determined by nuetron activation analysis (NAA). All irradiation of food samples were done at a pnueumatic transfer system (thermal nuetron flux : 1 $\times$1013n/$\textrm{cm}^2$.s) of the TRIGA MarkIII research reactor in the Korea Atomic Energy Research Institute . The results indicated that the iodine content was high in seaweeds, fishes, and iodine-enriched eggs in that order and very low in grain, beans , fruits and vegetables. Edible seaweeds contained iodine levels of between 13,700 and 1,790, 600$\mu\textrm{g}$/kg. Levels of iodine in fishes and shellfishes were between 478 and 2, 840$\mu\textrm{g}$/kg. Ordinary eggs contained 314$\mu\textrm{g}$/kg iodine, but iodine -enriched eggs contained 1,869$\mu\textrm{g}$/kg. The average concentration of iodine in milk was 207$\mu\textrm{g}$/kg. There was seasonal variation in the iodine content of milk , levels were highest in winter milk(230$\mu\textrm{g}$/kg) and lowest in summer milk(180$\mu\textrm{g}$/kg).The idodine contents of most vegetables and fruits were below 10$\mu\textrm{g}$/kg. The iodine contents of most vegetables and fruits were below 10$\mu\textrm{g}$/kg. From high to low , the sequence of foods with high iodine content in one serving was as follows ; sea tangle , sea mustard, iodine-enriched eggs, fish , laver and milk. This study may provide basic data on the iodine content of foods consumed by Korean which have not yet been analyzed .