• 한국동물학회지
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• 제29권2호
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• pp.75-78
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• 1986

Karyotypes of Korean spotted serpent head [Channa argus (Cantor)] were analyzed to obtain a basic information on the cytogenetics of this fish. Diploid chromosome numbers were found to be 48, of which 2 were submetacentric, 10 were submeta- or subtelocentric, and 26 were acro- or telocentric chromosomes without notably hetermorphic sex chromosomes. Cytogenetical implications of the results are discussed.

• 한국어병학회지
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• 제23권1호
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• pp.119-122
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• 2010

Mortality and gill lesions in snakehead, Channa argus (body length range, 20.3-22.2 cm) reared in a aqua-farm in Busan, Korea, were associated with a dense bloom of Apiosoma-like ciliate, Order Petrichida. The size of parasite was $48.83{\pm}7.75{\mu}m{\times}14.29{\pm}2.66{\mu}m$. Histological examination revealed that a severe edema and collapse of the gill tissue were observed in a number of samples of snakehead. The mechanism of gill damage was likely due to physical irritation by the parasite. It is believed that this is the first report of Apiosoma-like ciliate in cultured fish in Korea.

• 한국어병학회지
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• 제23권1호
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• pp.113-118
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• 2010

The present work describes myxozoan parasite found in the skin of cultured snakehead, Channa argus fingerings (total length, 5.5~7.2 cm) from Busan, Korea. Nature spores and plasmodia were found in the skin mucus of infected fishes. In fresh state, the total length of the spore was $27.96{\pm}2.50{\mu}m$. The size of spore body was $14.16{\pm}1.78{\mu}m{\times}4.88{\pm}0.61{\mu}m$. The polar capsules were pyriform and the size was $5.57{\pm}0.66{\mu}m{\times}1.36{\pm}0.33{\mu}m$. This is the first report of Henneguya sp. from cultured fish species in Korea, and further studies are necessary for definitive identification.

• 한국수산과학회지
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• 제45권2호
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• pp.114-121
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• 2012

A novel neuropeptide was isolated from the skin of the snakehead Channa argus using the dorsal retractor muscle (DRM) of a starfish Asterina pectinifera as a bioassay system. The amino acid sequence of the purified peptide was analyzed using automated sequencing and MALDI-TOF mass spectrophotometry. The primary structure of the purified peptide was determined to be Pro-Ala-Leu-Ala-Leu. To investigate the complete primary structure of this peptide, Pro- Ala-Leu-Ala-Leu-OH and Pro-Ala-Leu-Ala-Leu-NH2 were synthesized. The chemical and pharmacological properties of the synthetic peptides were compared with those of the native peptide. Both the native peptide and synthetic Pro-Ala- Leu-Ala-Leu-OH had identical behaviors on the reverse-phase and cation-exchange HPLC chromatograms. Synthetic Pro-Ala-Leu-Ala-Leu-OH showed contractile activity on the DRM, and the threshold concentration of this peptide was approximately $10^{-8}$ M. The maximal contractile effect ($E_{max}$) of this peptide was $294{\pm}45.4$% at $10^{-5}$ M.

• 한국어병학회지
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• 제1권2호
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• pp.95-101
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• 1988

During the period from August through October, 1988, 50 isolates of Edwardsiella tarda were isolated from 6 diseased cultured Channa argus in Dunchi island and Myung-ghi, near Pusan in Korea were examined by studying their biochemical and antibiotical reactions. The ill animals moved slowly and irregular-formed swimming at the surface of the corner. The symthoms were necrosis with hemorrhage on the body surface, head, gill region, and mouth. Some fish were observed dropsy of the belly. The bacteria grew slowly on Double Salmonella-Shigella agar, 24h, at $37^{\circ}C$ to form relatively small size (2mm diameter), smoothed and convexed form with transient or black in center of the colonis. They gave negative reactions to Voges-Proskauer, Simmon's citrate, urea, KCN (in growth), gelatin, arginine dehydrolase, phenylalanine deaminase and many sugars. The isolates showed positive reactions to $H_2S$ (in KIA agar), indol, Methyl-Red, motility, lysine and ornithine decarboxylase, and gas from glucose. 8 drugs tested as chloramphenicol, colistin, gentamicin, kanamycin, lincomycin, nalidixic acid spectinomycin, and tetracycline. All cultures were resistant to colistin, lincomycin and spectinomycin respectibly, but sensitive to kanamycin and nalidixic acid. Three strains showed resistance to chloramphenicol and 2 isolates among them were resistant to two drugs(gentamicin and tetracycline), coincidentally.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 1998년도 수산관련공동학술대회발표요지집
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• pp.373.1-374
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• 1998

• 한국수산과학회지
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• 제23권5호
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• pp.353-360
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• 1990

The bacterium Edwardsiella tarda was injected into healthy snakeheads (Channa argus) in order to prove the causative agent of ascite. The bacterium dominantly isolated from 2 cultured ascite snakeheads was injected into fish by the dose of $5\times10^6$ CFU/ 0.25ml, but the same dose of $0.65\%$ physiological saline was injected into the each control. The injected fish was divided into 4 groups such as intraperitoneal, intramuscle, control intra-peritoneal and control intramuscle according to their injection points. Each was composed of 10 healthy snakeheads respectively. Ascites and haemorrhagic ulcers became distinct 5 days after injection, but controls did not show any abnormal symptoms during the experimental period. Edwardsiella tarda was reisalated out of the injected fish's ascite, liver, kidney, spleen and haemorrhagic ulcer on the skin. Regardless of the injecting methods, liver was necrotized more severely than any other internal organ, but both the glomeruli of kidney and spleen were considerably damaged. Necrosis of muscle and a number of leucocytes were observed at the ulcerous region of the intramuscular injected fish. It is concluded that judging from the above results the Edwardsiella tarda is a causative agent to cause ascite in snakehead.

• 미생물학회지
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• 제30권3호
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• pp.164-170
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• 1992

본 연구는 한국산 양식 가물치에 큰 피해를 주는 출혈성 궤양증의 원인과 병리를 연구할 목적으로 수행되었다. 가물치의 출혈성 궤양증은 그 원인이 세균성이었고 궤양 및 장기로부터 분리된 Aeromonas veronii 가 주원인균이었다. A veronii 를 건강한 가물치의 피하에 인공 접종한 결과 양식 가물치에서 관찰된 병증과 유사한 궤양을 유발시켰다. 초기 증세는 주사부위를 중심으로 피부에 붉은 반점이 나타났고, 점차 확대되면서 피부가 탈락되고 출혈이 수반되었다. 곧이여 근육괴사가 진행되어 조사된 반대쪽에 구멍이 뚫렸다. $10^{5}$/CFU/0.25 ml 의 세균은 복강주사시 72시간이내에 시험개체의 50%가 치사되었다. 본 균은 cephalothin, chlorampenicol, gentamicin, tetracyline 등의 항생제에 감수성을 나타내었다.

• 한국균학회지
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• 제27권1호통권88호
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• pp.32-38
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• 1999

양식 가물치로부터 Saprolegnia sp.를 분리하고 그들의 일부 생리학적 특성과 제어를 위한 식물 추출물(精油)을 탐색하였다. 분리된 Saprolegnia sp. 영양체 생장 최적 온도는 $25^{\circ}C$이었고, 최적 pH는 6.0이었으며, 최적 NaCl 농도는 0%이었다. 또한 phosphate 10 mM 농도와 casamino acid 10mg/L농도에서 균사의 생장은 잘되었다. Saprolegnia sp.의 제어 정도를 조사하기 위해 쑥, 편백, 측백나무로부터 정유를 분리하여 10, 100, 500, 1,000, 1,500, 2,000ppm에서 처리한 결과 쑥 정유는 처리농도 10 ppm 이상 농도에서부터 억제 양상이 나타나다가 농도가 높아질수록 더 많은 억제양상을 나타냈다. 측백과 편백나무 정유를 처리한 것에서는 10ppm이상 처리 농도에서부터 억제되기 시작하여 그 이상의 처리 농도에서는 상당한 균사 생장 제어 효과를 나타내다가 500 ppm 이상 처리 농도에서는 완전한 제어 효과를 나타냈다. 또한 Saprolegnia sp.에 감염된 가물치의 조직 병리학적인 조사를 실시한 결과 균사가 감염된 근육조직 부분에는 깊은 곳까지 균사가 침투하였고, 아가미의 세포는 곤봉형태를 나타냈으며, 간조직 세포에서는 일부가 괴사되었고 부분적으로 ceroid 물질이 침착되어 있었다. 또한 비장조직 세포에서는 일부 괴사된 세포를 관찰하였고, ceroid 물질의 침착을 볼 수 있었다. 신장조직은 세뇨관의 상피세포에서 일부 괴사를 관찰하였고, 조혈 조직에는 ceroid 물질의 침착상태가 나타났다.

• 대한수의학회지
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• 제36권2호
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• pp.297-303
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• 1996

가물치의 위장관 내분비세포의 부위별 분포 및 출현빈도를 면역조직화학적으로 관찰하였던 바, secretin 면역반응세포들은 위의 분문부와 위저부의 상피 또는 장선부에서 소수로 출현하였다. Motilin과 GRP 면역반응세포는 장의 원위부와 위저부의 상피에서 극소수로, PYY 면역반응세포들은 유문맹낭부위와 장의 근위부에서 소수 또는 극소수로 각각 관찰되었다. Substance P 면역반응세포들은 위저부에서 장의 원위부에 걸쳐 소수 내지는 비교적 다수의 출현빈도를 보였으며 또한 장의 원위부 고유층에서는 신경세포가 양성반응을 보였다. 그러나 neurotensin, met-Enk, GIP 면역반응세포들은 전장관에서 관찰할 수 없었다.