• 한국어병학회지
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• 제31권1호
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• pp.35-39
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• 2018

Atypical furnculosis caused by atypical Aeromonas salmonicida, is an emerging problem of farming of rockfish (Sebastes schlegeli) in Korea. In this study, protection against atypical furunculosis was compared in rockfish vaccinated with A. salmonicida formalin killed cell (FKC) and adjuvant containing FKC. The formalin inactivated A. salmonicida vaccine provided a low protection of 20% and 10% relative percent survival (RPS) at 44 and 58 days post vaccination. However, addition of adjuvant (squalene and aluminum hydroxide) into inactivated A. salmonicida vaccine clearly enhanced the level of protection showing 70% and 50% RPS at 44 and 58 days post vaccination.

• 한국동물위생학회지
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• 제18권1호
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• pp.22-32
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• 1995

A partial characteristics and pathogenicity of Aeromonas salmonicida strain isolated from diseased cultured eel were studied. On the biochemicial characteristics of the isolate strain was classified into atypical Aeromonas salmonicida : the characteristics of the isolate strain differed from those of the subspecies of Achromogenes, masoucida and salmonicida. It strain was named atypical Aeromonas salmonicida EL-1 and it grew at optimal pH 7.5 and l% Nacl. In the pathogenicity test, at one to two days post infection, the motality of artificially infected eels with $1{\times}10^8$ and $1.0{\times}10^7$ cfu/fish group was 100%, and at three days pos-infection, in the $1.0{\times}10^6$ /cfu /fish infected group, the epizootic haemorrhagic ulcer was developed, and haemorragic red sports were formed around abdomen and fins and its died (40%). Total cell protein peptide bands of the A. salmonicida EL-1 were presented betweeon 11.8~102 Kd in molecular weight by the electrophoretic analysis and appeared 28 bands in all. Drug sensitivity of atypical A. salmonicida EL-1 strain was sensitivity to chlorampenicol, gentamicin, kanamycin, streptomycin and sulfamethoxazole /trimethoprim and intermidiate to ampiclin and neomycin resistant to cephalotin, erythromycin, lincomycin and tetracycline.

• 한국임상수의학회지
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• 제27권3호
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• pp.289-294
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• 2010

경남 산청지방에서 쏘가리를 양식하던 어장에서 대량폐사가 발생하였다. 주요 증상으로 전신 피부에서 궤양이 진행되었고 조직학적으로는 주요 실질 장기에서 세균의 집락과 주변부위로 염증 및 괴사가 관찰되었다. 분리된 세균을 API 20E 및 API 20NE를 이용하여 생화학적 검사를 실시한 결과 Aeromonas salmonicida subsp. salmonicida (typical A. salmonicida)로 진단할 수 있었다. 그러나 atypical A. salmonicida와 typical A. salmonicida로 구분할 수 있는 PCR 기법을 실시한 결과, 본 세균은 atypical A. salmonicida임을 확인할 수 있었다. 본 연구는 우리나라 쏘가리에서 A. salmonicida로 인한 발병의 최초 보고임과 동시에, A. salmonicida의 정확한 진단을 위해선 생화학적 검사가 아닌 PCR 검사를 이용한 진단을 실시해야 함을 제시하였다.

• 한국어병학회지
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• 제35권2호
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• pp.247-250
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• 2022

About 6.7% mortality was reported in a starry flounder (Platichthys stellatus) aquaculture farm in 2022. Most of the diseased fish showed a loss of pectoral fin, hemorrhages on muscle and gills, pale gills, enlarged spleen, and nodules on kidney. Parasites, fungi or viruses (viral hemorrhagic septicemia virus and hirame novirhabdovirus) were not detected from diseased fish. However, numerous bacteria were isolated from liver, spleen and kidney. Nucleotide sequences of the A-protein-encoding virulence array protein gene (vapA) of the bacteria showed 99.93% identity with Aeromonas salmonicida subsp. masoucida. This study is the first report of isolation of atypical A. salmonicida in cultured starry flounder in Korea.

• 한국어병학회지
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• 제32권2호
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• pp.81-89
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• 2019

As an epidemiological survey, mortality of marbled rockfish, Sebastiscus tertius observed from a fish farm in Gyeongnam province of South Korea. The major macroscopic sign of the diseased fish was severe multifocal dermal ulceration. Histological observation revealed inflammation, necrosis and colonization of bacteria in various tissues (gill, liver, spleen and kidney). Bacteria was isolated from spleen and kidney in moribund and mortality fish. Seven bacterial isolates from the diseased fish were identified as Aeromonas salmonicida subsp. salmonicida using API 20E and 20NE, API 50CH API ZYM system. Under light microscopy, infected marbled rockfish showed the lifting of the lamella epidermal layer, edematous changes and hypertrophy of epithelial cell in the gill filament. The atrophy of the mucosal fold, erythema in the intestine, and the necrosis of hematopoietic tissue and renal tubule cells with karyolysis were observed in the kidney. In this study was demonstrated the histological reaction of red marbled rockfish infected by Aeromonas salmonicida. Furthermore, this is the first account of extensive dermatitis in Sebastiscus tertius due to atypical A. salmonicida infection, which has high potential in aquaculture among native fish species.

• 한국어병학회지
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• 제28권3호
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• pp.145-155
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• 2015

The pathogenecity of atypical Aeromonas salmonicida was studied in healthy Oreochromis niloticus. Inoculum at concentration of $1.5{\times}10^8CFU/ml$ and $3{\times}10^8CFU/ml$ was injected into healthy fish through intramuscular and intraperitoneal injections. Experimentally infected Oreochromis niloticus showed ulceration at the dorsal musculature and trunk region in addition to black coloration, congested gills, exophthalmia, and ocular hemorrhage. Congested liver and kidney were recorded in post-mortem examination. Mortality of the experimentally infected Oreochromis niloticus reached 100% after intramuscular injection at concentration of $3{\times}10^8CFU/ml$. Histopathological investigation of infected organs was also performed. There was a focal area of bundles of skeletal musculature showing hyalinization. In addition, hyperplasia, congestion, and fusion were noticed in the gill lamellae. There was also congestion in the blood vessels in the ocular chamber. Severe congestion was also noticed in the central vein of liver associated with focal aggregation of the melanin pigmented cells in the parenchyma. Degenerative changes were noticed in the epithelial cells lining of kidney tubules. Plant extracts carvacrol and its biological precursor cymene were found to be effective in treating experimentally infected Oreochromis niloticus at concentration of 100 or 200 ppm.