• 한국수산과학회지
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• 제19권5호
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• pp.509-517
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• 1986

한실포 잘피밭에 서식하는 어류의 종조성과 출현량의 계절적 변동을 파악하기 위해 1985년 2월부터 1986년 1월까지 1년간 매달 어류를 조사한 결과는 다음과 같다. 1. 조사 기간동안 19과 35종에 속하는 총 4,646마리의 어류가 채집되었으며, 이들은 대부분 10cm이하의 소형 어류였다. 2. Pholis taczanowskii, Pseudoblennius cottoides, Tridentiger trigonecephalus 및 Syngnathus schlegeli의 4어종이 가장 많이 채집되었으며, 채집된 총 개체수의 약 $64\%$를 차지하였다. 3. Sebastes inermis, Platycephalus indius 및 Limanda yokohamae 등과 같은 상업성 어종의 어린치어들도 잘피밭에서 채집되었다. 4. 종조성과 출현량의 계절적 변동은 잘피밭을 이용하는 어류 군집의 특징이었다. 어류의 최대 출현량은 4월과 10월에 나타났으면, 겨울에는 상당히 낮은 출현량을 보였다. 주요 어종은 각자 독특한 출현량의 계절적 변동 양상을 보였는데, 일반적으로 한 어종의 최대 출현량이 나타나는 시기와 다른 어종의 최대 출현량이 나타나는 시기는 $1{\sim}3$개월 정도 분리되어 있었다.

• 한국양식학회지
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• 제12권2호
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• pp.115-122
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• 1999

Exposure experiments during the egg development were conducted to assess the influences of 5 different concentrations (0, 25, 50, 75 and 100%) of water-soluble fraction (WSF) of Kuwait crude oil on the eggs and larvae of black seabream (Acanthopagrus schlegeli), red seabream (Pagrus major) and olive flounder (Paralichthys olivaceus). All experiments were triplicated. Hatching time and hatching rate were examined on the eggs. The median lethal time ($LT_{50}$), morphological abnormality and swimming activity (swimming frequency and speed) of larvae were also investigated. The time and rate of egg hatching were not significantly influenced by WSF on the eggs of the fishes. The larvae exposed to WSF during the egg development were also not significantly influenced on the $LT_{50}$ and swimming activity. But the higher morphological abnormalities of notochord were observed from the larvae in 100% WSF exposure.

• 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.

• 한국수산과학회지
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• 제35권4호
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• pp.315-320
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• 2002

통영을 중심으로 한 우럭생산량은 연간 1,813M/T에 이르고 있으며, 과잉생산에 대한 우려가 제기되고 있다. 이와 같은 우려를 개선시키고 기능성 어류에 대한 소비자의 기대감을 충족시키기 위하언 성장촉진, 항암, 면역증강, 혈중 LDL 함량 저하효과를 가진 것으로 알려져 있는 CLA를 이용한 기능성 우럭생산의 가능성을 검토하였다. Artemia 영양강화시 CLA를 $0.5\~5.0\%$ 첨가하였을 경우 Artemia중 지방산조성의 변화를 조사한 결과 CLA 첨가량이 증가할수록 CLA 함량은 높아졌고, 동시에 Artemia 특유의 지방산조성을 나타내어 지방산 대사에 특별한 영향을 미치지지는 않는 것으로 나타났다. 8주 사육 후 우럭근육 중 n-6지방산의 함량이 높아 사료에 첨가된 지질의 영향을 받은 것으로 나타났다. 그리고 n-3/n-6 PUFA 비가 자연산 우럭의 3.95보다 현저히 낮아 CLA 첨가가 많을수록 성장을 저해하는 것으로 나타나 배합사료 중의 DHA 첨가가 증가되어야 할 것으로 여겨진다. 그러나 이를 섭취한 우럭 근육 중 총 CLA 함량은 급이 량에 따라 각각 $6.57\~16.07\%$가 축적되어 CLA는 다른 지질성분과 함께 어체내 대사과정을 거치는 것으로 나타났다. 우럭의 성장도, 사료효율, DHA/EPA 비, n-3/n-6 PUFA 비, 활력테스트, 혈액지수 둥을 비교하였을 때 $1.0\%$ CLA 첨가가 적절한 첨가량인 것으로 생각된다.

• 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.

• 한국발생생물학회지:발생과생식
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• 제8권1호
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• pp.11-17
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• 2004

북대서양에서 상업 적으로 중요한 해산어류인 Haddock Melanogrammus aeglefinus의 자치 어 발생과정과 성장을 조사하였다. 자치어는 부화 후 67일까지 사육실 조건에서 사육되었고 주기 적으로 표본한 재료를 실체 현미경으로 관찰하였다. 발생단계별 크기 변화는 부화 후부터 지속적인 성장을 보여 Y=4.07 $e^{0.037}$( $R^{2}$=0.9978)의 성장식을 나타내었다. 부화 직후의 자어는 전장 4.9 m로 장방형의 난황을 가지고 있었다. 초기 먹이섭취는 부화 후 7일에 시작되었으나 부화 후 16일 째 전장 6.8 m때에 난황이 완전히 흡수되어 후기 자어 단계가 되었다. 부화 후 16~52일의 기간에 부속기관의 발달이 활발히 진행되었으며, 전장 41.3 mm인 부화 후 61일에 턱수염은 완전히 발달되지는 않았지만 치아, 측선, 체측의 검은 반점 등은 성어와 같은 모습의 치어 단계에 도달하여 본 종은 이 시기 이후로 먹이와 생태적 행동변화가 일어나는 것으로 추정된다.다.

• 생태와환경
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• 제48권4호
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• pp.272-279
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• 2015

The aim of this study was to assess the interaction between Daphnia similis and various organisms related to the rice paddy ecosystem. We selected several organisms that are likely to prey on D. similis and evaluate predation rate as well as responses of D. similis to the chemical compounds exuded by these organisms. As a result of predation experiment, larval dragonfly (Anax parthenope) and Triops longicaudatus were clearly shown decreasing abundances of D. similis. Especially, Triops longicaudatus was observed higher feeding rates on D. similis than larval dragonfly. Chemical compounds from the vertebrates such as fish (Misgurnus anguillicaudatus, Pseudorasbora parva, Micropterus salmoides) and tadpole of frog (Rana nigromaculata) did not affect the life history of Daphnia. However, a potential predatory fish P. parva induced significantly longer tail spine in Daphnia. In addition, among the invertebrates (T. longicaudatus, A. Parthenope, Micronecta spp., Palaemon paucidens), chemical compounds exuded by T. longicaudatus induced shorter body and significantly longer tail spine in D. similis.

• Fisheries and Aquatic Sciences
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• 제21권12호
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• pp.37.1-37.10
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• 2018

The larvae and juveniles of Porocottus leptosomus belonging to the family Cottidae were collected (n = 95, 3.9-16.5 mm in body length, BL) from Busan, Korea, in March 2015. The larvae and juvenile were identified using DNA barcoding as P. leptosomus, and their morphological description was presented in detail. The yolk-sac larvae (3.9-5.6 mm BL) body was slightly compressed, the head was large, the eye was round and large, and the anus was before the middle of the body. The preflexion larvae (5.2-10.0 mm BL) body length drastically increased; caudal fin rays began to occur. The flexion larvae (9.4-11.8 mm BL) notochord flexion started; dorsal, pectoral, and anal fin rays began to occur; pelvic fin buds are seen; they possessed a pair of parietal spine; and a pair of supraocular cirri was first to develop. At 12 mm BL, the notochord was completely flexed. The larva stage (3.9-12.6 mm SL) had the stellate melanophores in the head, isthmus, gut, and tail (along to the ventral midline). During the juvenile stage (11.4-16.5 mm BL), melanophores covered the head and began to form five black bands on the side of the body. The larvae of P. leptosomus spent pelagic life, but moved to the bottom during the juvenile stage. The larvae and juveniles of P. leptosomus differ from other cottid larval fishes by body shape, melanophore head pattern, and spine development. P. leptosomus can be distinguished from Porocottus allisi by morphological development and the occurrence of larval fish: preopercular spine development, melanophore pattern, and caudal fin development.

• Ocean and Polar Research
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• 제44권1호
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• pp.39-59
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• 2022

How in the Antarctic icefish, generally, and Pseudochaenichthys georgianus, in particular, otoliths increase in size and build new material as the fish ages and passes through different life phases is largely unexplored. Morphometric details of 3418 otoliths of Ps. georgianus from S. Georgia and 318 from S. Shetland, were processed and proportions of the amounts of collagen and aragonite removed by EDTA were determined for different age groups. Microstructural investigations showed that characteristics of the 3-dimensinal collagen net are the reason for the radial direction and orientation of the aragonite needles of approximately 1.0 ㎛ in length in larval and 2.3 ㎛ in length in adult specimens. Earlier generated increment layers from the primordial centre (PC) in the dorsal direction restrict those of the secondary centre (SC), causing new growth layer accretion in different directions. In the otoliths of larval Ps. georgianus, aragonite layers are 0.89 ㎛ wide while in juveniles and adults they measure 1.45-2.86 ㎛. Otoliths change from a sphere shape in the larvae to a longish object of irregular outline in the older stages. It is tentaively suggested that the observed otolith shape differences at distinct growth stages are due to physical effects related to swimming speeds at particular water depths and locations. To confirm that otoliths, apart from being useful for age analyses, could also serve to establish correlations between developmental stage and the oceanic environment the fish spend time in, further analyses using additional species and state-of-the-art methods like µCT imaging to evaluate otolith volumes and shapes are required.

• 한국수산과학회지
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• 제55권1호
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• pp.23-29
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• 2022

This study was carried out to clarify the egg, larvae and juveniles development of Misgurnus anguillicaudatus, and relationships of M. anguillicaudatus and M. mizolepis, Cobitididae Fishes. The adult fishes were collected in Samsan-cheon, Haenam-gun, Jeollanam-do, Korea and their spawning inducement was carried by ovaprim injections. The egg shape was circular and the size was average 1.12 mm. The eggs were hatched at 61 to 72 h after fertilization. The newly hatched larvae had an average 3.23 mm in total length (TL). At 5 days after hatching, the larvae reached to post larval stage and they were 10.3 mm in TL. At 19 days after hatching, it reached to juvenile stage and was 25.3 mm in TL. The egg size of M. anguillicaudatus was almost same as M. mizolepis but the hatching period of M. anguillicaudatus has taken longer. It was possible for interspecific distinguishability of M. anguillicaudatus and M. mizolepis when their larvae reached to juvenile stage by the development of keel-like ridges.