• 수산해양기술연구
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• 제47권4호
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• pp.419-427
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• 2011

Simulation technique for the fish behavior was applied to estimate fish school movement in the cage net. Individual-based fish behavior model (Huth and Wessel, 1991) was evaluated in a free area to understand the characteristics for the model, and the movement in the cage net was simulated by defining the fish reaction against the displacement of cage net. As a result, the distance to the net was not considerably changed and the space among fishes in cage net was slightly decreased by reducing the net space. Swimming area was, however, significantly affected by changing the net space and the relationship between swimming area and net displacement was theoretically estimated as y=-0.21x+1.02 ($R^2$=0.96). these results leads the conclusion that individual-based model was appropriated to describe the fish school reaction in the cage net and be able to use for evaluating the influence on cultured fish.

• 한국수산과학회지
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• 제19권3호
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• pp.195-211
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• 1986

한국산 양식어의 식품성분을 개선하기 위한 학술적 기초자료를 얻기 위하여 뱀장어, 가물치, 잉어를 천연산과 양식산으로 구분하고, 식품성분에 관하여 분석비교한 연구결과는 아래와 같다. 1. 담수어의 일반 성분중 공통적 특징은 천연산은 조단백질 함량이 많고 양식산은 조지질 함량이 많았다. 2. 천연산 뱀장어, 가물치, 잉어육 중의 무기질중 나트륨, 칼리움, 칼슘, 마그네슘 등은 분석한 9종의 무기질 총량의 $99.75{\sim}99.90%$를 차지하였으며, 양식산에서도 이들 4종의 무기질이 $99.52{\sim}99.92%$의 많은 양을 나타내었다. 또한 사료도 이들 4종의 무기질이 $99.68{\sim}99.92%$로 많았다. 3. 지질획분은 중성지질이 뱀장어, 가물치, 잉어 모두 $55.7{\sim}95.8%$로서 대부분을 차지하고 있으나 가물치는 인지질이 $24.5{\sim}41.5%$로서 뱀장어, 잉어에 비하여 많았다. 4. 천연산 및 양식산 뱀장어, 가물치, 잉어의 중성지질은 triglyceride가 $85.0{\sim}95.2%$로서 대부분을 차지하였고, 그외에 diglyceride, monoglyceride, free sterol 및 sterol ester, hydrocarbon 등이 소량 검출되었다. 5. 뱀장어와 잉어의 지질의 조성은 phosphatidyl choline이 $71.3{\sim}83.9%$로 대부분을 차지하였고 phosphatidyl ethanolamine of $12.1{\sim}23.5%$, phosphatidyl serine이 $2.1{\sim}9.8%$로 소량 확인되었다. 또한 가물치의 인지질조성은 phosphatidyl choline이 $50.7{\sim}64.5%$로서 그 함량이 뱀장어와 잉어에 비하여 다소 낮았다. phosphatidyl choline은 천연산이 양식산에 비해 그 함량이 많았으며 phosphatidyl ethanolamine 및 phosphatidyl serine은 양식산이 많았다. 6. 총지질의 지방산 조성은 뱀장어, 가물치, 잉어 모두 천연산은 $C_{16:0},\;C_{20:5}$가 많았고, 양식산에는 $C_{18:1},\;C_{18:2}\;,C_{22:6}$이 많았다. 중성지질의 지방산 조성은 총지질과 유사하였으며, 인지질은 양식산이 $C_{18:1}$과 $C_{18:2}$가 많았고, 또한 당지질은 천연산이 $C_{20:5}$와 $C_{22:6}$이, 양식산은 $C_{18:2}$가 많았다. 7. 양식어와 이들 사료중 총지질의 지방산 조성을 보면 monoene산은 사료보다 양식어쪽의 함량이 높았고, 포화산과 polyene산은 사료보다 양식어쪽이 낮은 경향이었다. 8. 천연 및 양식산 뱀장어의 아미노산 총량은 각각 $16.65\%$및 $15.99\%$로서 양자간에 거의 차이가 없었으며, 함량이 많은 것은 glutamic acid, leucine, aspartic acid, lysine 순이었다. 가물치는 천연산이 $18.06\%$이며, 양식산은 $18.52\%$이며 천연산은 glutamic acid, alanine, glycine 및 leucine은 많았으며 양식산은 aspartic acid 및 proline이 많았다. 또한 잉어는 천연산이 $16.94\%$, 양식산은 $20.95\%$로서 양식산은 glutamic acid, aspartic acid, glycine, proline 및 alamine이 천연산에 비해 그 함량이 다소 많았으나 이외의 아미노산 함량은 큰 차이가 없었다. 9. 양식산 뱀장어의 유리아미노산은 aspartic acid가 총 유리아미노산의 약 $1.0\%$였으나 천연산은 $2.9\%$를 차지하였다. 반면 histidine, arginine 및 tyrosine등은 양식산이 천연산보다 약 2배 가량 많았다. 그러나 양식산지에 따른 유리 아미노산 조성비는 큰 차이가 없었다. 가물치의 경우 arginine, aspartic acid, glutamic acid, methionine, phenylalanine 함량은 천연산이 양식산보다 그 함량이 많았으나 lysine, histidine, glycine 및 alanine은 그 반대였다. 천연산 잉어의 유리아미노산 중 histidne, glycine 및 lysine 함량이 총유리아미노산의 $76.9\%$를 차지하였다. lysine, histidine, aspartic acid, alanine, valine 및 leucine은 양식산에 비해 천연산의 함량이 많았으나 glycine과 tyrosine은 그 반대였다. 10. 양식 뱀장어 육중의 유리아미노산의 필수아미노산패턴과 사료중의 필수아미노산패턴과는 거의 같은 경향이었다.

• 한국식품위생안전성학회지
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• 제12권4호
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• pp.294-299
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• 1997

A study was conducted to determine contamination status of fish sold at wholesale market in Seoul. A total of 79 samples (35 different kindry fish) were collected from the wholesale market. E. coli and coliform group bacteria were cultured and tested for sensitivity against antibiotics. The results are summarized as follows; 1. E. coli was isolated from 23 out of 79 samples (29.1%), and coliform groups from 53 out of 79 (67.1%). 2. Of coliform group, Citrobacter freundii was the most common and Enterobacter clacae was the next. 3.23 E. coli strains isolated from fishes were resistant to Oxacillin, Erythromycin and Lincomycin, meanwhile 23 E. coli strains were sensitive to Cefoperazone, Ceftazidime, Imipenem, and Ciprofloxacin.

• 한국어병학회지
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• 제17권3호
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• pp.179-189
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• 2004

Morphological structure and sporogenesis of myxosporean parasite, Parvicapsula anisocaudata from cultured olive flounder, Paralichthys olivaceus were examined by light and transmission electron microscopies. Numerous round early stages, spindle-shaped disporic or monosporic pseudoplasmodia, asymmetrical thin-walled mature spores were found inthe lumen of renal tubule and urinary bladder. Long pseudopodia or short projections from cytoplasm of pseudoplasmodia make the parasite attach firmly to host tissues. Spore development was mono- or disporous with no pansporoblast formation. Sporoplasmic cell was partially surrounded by two capsulogenic cells, and capsulogenic cells were enveloped by two flattened valvogenic cells. Capsulogenesis and valvogenesis followed general patterns seen in that of other myxosporean.

• 한국어병학회지
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• 제19권2호
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• pp.109-117
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• 2006

A new myxosporean species Ceratomyxa oplegnathus n. sp. was found from the gallbladder of cultured rock bream, Oplegnathus fasciatus. Mature spores were 44.14 ± 2.41 (39.04-48.41) ㎛ in length, 8.52 ± 0.36 (7.9-9.26) ㎛ in width in sutural view. Spores contained two spherical polar capsules measuring 3.04 ± 0.2 (2.71-3.37) ㎛ in diameter and a binucleated sporoplasm. Each polar capsule had a 5-6 coiled polar filament, and was situated near the sutural line. In ultrastructural observation, asynchronous divisions of generative cells without pansporoblast formation gave arise to 2 spores within a trophozoite. Sporoplasmic cell in the sporoblast was binucleated, and capsulogenic cells had large amounts of rough endoplasmic reticulum, external tubules, and capsular primordia.

• 대한수의학회지
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• 제47권3호
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• pp.299-302
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• 2007

Neoheterobothrium hirame (N. hirame) is a large blood-feed gill-worm infecting the highly prized olive flounder. The present study was reported the occurrence and elimination of Neoheterobothrium infection from young cultured oliver flounder in the western coast of Korea. Flounder (weight 18-25 g, length 10-15 cm) were obtained from a cultured farm at Taean of Korea at May 2006. A lot of flounder died with serious anemia. We isolated N. hirame from the buccal cavity wall of dead flounder. Adult parasites were 5-15 mm in total length, with 4 pairs of clamps on the pedunculated haptor and isthmus region embedded in host tissue, while immature and sub-adults were identified the attachment to the gill filaments, rakers and arches with the clamps. All fish with infection were treated with 8% NaCl-supplemented seawater for 1 and 10 min at $22^{\circ}C$, respectively. The significant reduction in mortality (6.7%) was observed among fish treated with 8% salt water for 10 minutes, when compared with that of non-treatment group (100%).

• 한국어병학회지
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• 제17권2호
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• pp.99-103
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• 2004

2001년 10월과 2004년 3월 전북 고창군의 육상수조에서 자체 순환방식으로 사육중인 황복에 발생한 대량폐사의 원인을 조사하였다. 발생시의 수온은 22.0-$\23.0^circ{C}$였으며, 외부 증상은 거의 없었지만 눈이 함몰하는 개체가 많았고, 아가미 표면에는 무수한 백점이 육안으로도 관찰되었다. 병어를 병리조직학적으로 조사한 결과 Cryptocaryon irritans의 감염에 의한 것으로 백점충은 아가미의 호흡상피 아래에 증생된 상피세포에 피포되어 기생하고 있었으며, 상피세포에는 점액세포의 증생이 현저하였다. 본 병에 의한 사망률은 100%로 이는 충체의 기생에 의한 아가미의 호흡면적의 감소와 점액의 과잉분비, 점액 과 수중부유물에 의한 새강 출구를 통한 호흡수의 방출 장애 등에 의한 호흡곤란이 대량폐사의 원인으로 추정된다.

• 한국어병학회지
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• 제33권1호
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• pp.91-95
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• 2020

Fish bacterial diseases have spread and caused serious problem for cultured marine fish in Korea. The important bacterial disease affecting mariculture such as olive flounder (Paralichthys olivaceus) are caused by Edwardsiella tarda, Vibrio scophthalmi and Streptococcus parauberis. For the bacterial disease protection in aquaculture industry, the water treatment is needed in aquaculture system. During the last decades atmospheric pressure non-thermal plasma in contact with liquids have received a lot of attention of environmental and medical application. In this study, we determined the disinfectant effect in seawater and three major fish bacterial disease pathogens by using low frequency plasma treatment. Three fish bacteria (E. tarda, V. schophthalmi, S. parauberis) were not detected within 16 min, 150 min and 270 min of 20 L, 500 L and 1 ton seawater post low frequency plasma treatment, respectively. Three major fish bacterial disease pathogens were not detected within 2 min after the low frequency plasma treatment, suggesting that the low frequency plasma possess disinfectant effectiveness.

• 대한수의학회지
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• 제47권3호
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• pp.303-308
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• 2007

The high mortality (65.5%) of young olive flounder (Paralichthys olivaceus) showing skin ulcers occurred in fish obtained from a commercial cultured farm at Donghae on the eastern coast of Korea at March 2006. The dorsal skin showed ulcer lesions and large amount of mucus. We isolated Ichthyobodo sp. from the gill, and Vibrio anguillarum from the liver and kidney of dead and diseased fish. All of the fish infected with the V anguillarum and Ichthyobodo sp. were treated with 100 ppm formalin for 1 h, and treated with oxolinic acid for 4 h at $22^{\circ}C$, respectively. The formalin treated group was observed the low mortality (2.9%) when compared with high mortality of non-treated (82.9%), and of antibiotic treated group (85.9%) against mixed infections by Vibrio anguillarum and Ichthyobodo sp. organisms. We confirmed complete elimination against mixed infections of Vibrio anguillarum and Ichthyobodo sp. with 100 ppm formalin treatment.

• Ocean and Polar Research
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• 제23권3호
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• pp.279-284
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• 2001

The natural high productivity of temperate coastal waters in Korea can be used in advantage to reduce the feed costs for the cage-cultured marine carnivorous fish species. By using the night-lights methods an alternative of supplementary feeding strategy can be offered to the cage farmers and maintain sound environmental conditions that could enhance maximum sustainable yields. The aim of this study was to investigate the effects of night-lights which shown positive results on feeding and growth in sea cage cultured rockfish, Sebastes schlegeli. The study showed that for the water around overhead illuminated sea cage, higher zooplankton density was observed at night than during the daytime. Increased amounts of for-age, evidenced by stomach content analyses were observed in the early evening, but decreased amounts were observed in the morning and afternoon. That is, feeding activities of the fish were most intensive from midnight to dawn. In a three month feeding experiment, the results showed that night-lighted groups were superior to groups with the highest feeding efficient. This study suggested that the evidence that night-lights superimposed on only day-lights enhance growth of rockfish in sea cages during summer and winter, with timing of exposure affecting growth of juvenile fish. The capability to control the feeding behavior of marine life via manipulation and external stimuli could considerably benefit the advancement of sea cage aquaculture in coastal areas.