• Journal of fish pathology
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• v.27 no.1
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• pp.77-83
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• 2014

The monitoring was performed to survey the mortalities and medications occurred in the inland aquaculture farms of olive flounder in South Korea from May to October, 2012. Both of the indirect inquiry for entire inland farms and the sample survey for selected farms were carried out. The aquatic organism disease inspectors, who have the national licenses for the diagnosis and prevention of aquatic organism diseases and have close relationship with the farms, investigated the rates and causes of mortalities according to the standard manual. The cumulative mortalities rate by the indirect inquiry on 565 farms, was calculated to 27.18%, and the mortalities rate by infectious diseases was 22.64%. Otherwise, the mortalities rate by sample survey on 60 farms was 25.50%, 19.33% of them were caused by infectious diseases. The high mortality rates were recorded by scuticociliatosis, non-infectious loss, streptococcosis, VHS, artificial eliminations, vibriosis and gliding bacterial disease. Streptococcosis and non-infectious mortality caused to serious loss in productivity and economy of the farms, because of their outbreaks in the flounder groups over 600 g. The monitoring of medications in the selected farms revealed that formalin for the treatment of external parasites, such as scuticociliates, was the most commonly used drugs in the farms. As the antibiotic medications, amoxicillin and florfenicol for streptococcosis, and oxytetracycline and neomycin expecting wide antibacterial spectrum, were frequently prescribed.

• Journal of fish pathology
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• v.8 no.1
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• pp.57-67
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• 1995

Twenty-four hours, acute toxicity and the histopathological effect of formaline to flounder, Paralichthys olivaceus larvae were examined. The $LC_{50}$ values obtained to farmaline were 2,520 ppm in 1 hour treatment. 1.610 ppm in 2 hours treatment, 868 ppm in 4 hours treatment and 141 ppm in 24 hours treatment. Many pathological features such as hypertrophy of mucous and epithelial cells in secondary gill lamella, hyaline droplet degeneration of tubular epithelial cells in the proximal convoluted segment of renal tubules, focal or massive necrosis in liver cells and pycnotic nucleus in heart cells were recognized. The above results were discussed in relation to the application of formaline as therapeutic agent in flounder disease.

• Journal of fish pathology
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• v.37 no.1
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• pp.61-69
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• 2024

In this study, bacterial disease monitoring was conducted from July to November 2022 for three representative bacterial species (Streptococcus parauberis, Vibrio spp. and Edwardsiella piscicida) to investigate the occurrence of bacterial diseases in farmed olive flounder (Paralichthys olivaceus) on Jeju. Over a period of five months, 3,146 olive flounders were tested. The average length and weight of the olive flounder that were sampled for the disease were found to be 32.1 cm and 357.9 g, respectively. Bacteria were detected in 1,228 olive flounders, of which 24.6% were identified as Vibrio spp.. S. parauberis and E. piscicida were identified in 6.3% and 3.2% respectively, and 3% were unknown strains that could not be identified. Also, 41 (1.3%) olive flounders were found to have both S. parauberis and Vibrio spp. and 23 (0.7%) olive flounders were found to have both E. piscicida and Vibrio spp.. In particular, S. parauberis, Vibrio spp. (V. scophthalmi) and E. piscicida were detected simultaneously in one olive flounder. In fish infected with E. piscicida, the most obvious external signs were hernias and ascites.

• Journal of fish pathology
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• v.6 no.2
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• pp.219-231
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• 1993

The author introduces the preventive and therapeutic methods of diseases in Japanese flounder which have been conducted by the Fish Disease Laboratory, the Mikamewan Fishery Cooperative Union, Ehime Prefecture, since 1982. Prevention 1. Addition of a sand substrate in the culture pond was effective to prevent ulcer disease. 2. Bathing in 0.5ppm of copper ion was effective to prevent some parasites. 3. Low stocking density of the fish reduced an incidence of edwardsiellosis or gliding bacterial disease. 4. Removal of the diseased fish prevented thd spread of lyphoeystis. 5. So-called $\pi$-water was effective to prevent the fry from some diseases. 6. Immersion of the juvenile in a sodium nifrusylate solution during transportation was effective to prevent gliding bacterial disease. Therapy 1. Sodium nifrustylate or oxytetracycline was effective to cure gliding bacterial disease. 2. Bathing in formalin(150ppm) or freshwater was effective to cure scuticociliatidosis. 3. Erythromycin was effective to cure $\beta$-hemolytic Streptococcus sp. infection. 4. Bathing in a hydrogen peroxide solution(1.5%) was effective to cure white spot disease.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.3
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• pp.128-132
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• 2007

We identified a microsatellite marker, Poli121TUF, which appears to be significantly linked (P<0.001) with a lymphocystis disease virus (LCDV)-resistance gene in the olive flounder, Paralichthys olivaceus. The olive flounder is an economically important food fish, that is widely cultured in Korea, Japan, and China. Lymphocystis disease has spread in these countries and has seriously reduced the economic value of the fish. LCDV causes lymphocystis cells (LC) to form on the body surface, fins, gills, mouth, and intestine. Fish with LC lose commercial value due to their deformed appearance. The identified micro satellite marker can be used as a candidate locus for marker-assisted selection (MAS) in order to enhance the efficiency of selection for LCDV resistance in the olive flounder.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.457-458
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• 2000

Pefloxacine(PFX)은 기존 quinolone계 항균제의 단점을 보완한 fluoroquinolone계열의 합성 항균제로서 그람양성균과 그람음성균에 대해서도 살균효과가 뛰어날 뿐 아니라 내성균 출현 가능성이 비교적 낮은 장점이 있는 항균제로 보고되고 있다. 이러한 약리학적 특성 때문에 우리 나라에서도 양식어류 세균성 질병 치료제로 최근 사용량이 증가하고 있으나 현재까지도 어류를 대상으로 한 체내잔류 PFX의 정량분석방범과 PFX의 흡수, 분포, 해설 등 실제 약제 사용방법 설정에 필수적인 임상동태에 관해서는 연구가 되어 있지 않은 실정이다. 따라서 본 연구는 양식어류에 대한 PFX의 효과적인 사용방법을 확립하기 위하여 고속액체크로마토그라피(HPLC)를 사용하여 실험조건의 특이성 등을 검토하여 어체내 잔류 PFX의 최적 분석조건을 설정하였다. 그리고 주요 양식어류를 대상으로 PFX를 경구 투여한 후 시간경과에 따라 혈액을 채취하여 혈종에서의 약물동태학적 Parameter를 조사하였다. (중략)

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.261-262
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• 2001

어류는 수온에 의해 성장, 번식, 대사, 삼투압 조절 및 면역 등 생명활동에 영향을 받는다(Wendelaar Bonga, 1997). 여름철 우리나라 동해안에서 발생하는 냉수대로 인한 급격한 수온변화는 어류의 느린 성장과 질병 발생을 초래하는요인이 되는 것으로 알려져있다. 또한 발전소 인근수역은 고수온기인 여름철에 온배수의 영향을 받아 수온이 더욱 상승하게 된다. 수온의 급변이 어체의 생리적 변화를 야기시키고 스트레스요인으로 작용하여, 생체내 대사와 혈액성상의 변화를 일으키는 것으로 연구된 바 있다(Barton and Iwama, 1991). (중략)

• Journal of fish pathology
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• v.23 no.1
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• pp.137-143
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• 2010

Hot water extracts of 5 herbs were tested in-vitro for anti-bacterial, anti-fungal, anti-parasitical effects for possible use against fish diseases. Skullcap, Scutellaria baicalensis, was the most effective herb in these 5. The effects of skullcap in cultured flounder were examined for various physiological responses and bacterial disease-prevention follow as feeding skullcap absorbed diet for 4, 8, 12weeks. There were not any significant effects in physiological responses, except beneficial action of growth promotion. No definitive preventive activity was observed with experimental feeding of the extract against infected flounder. As we could not confirm in-vivo antibacterial effects of skullcap in flounder despite its in-vitro efficacy, further studies are needed to define the in-vivo efficacy.

• Journal of fish pathology
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• v.20 no.1
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• pp.33-40
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• 2007

Biochemical characteristic of Streptococcus iniae and Streptococcus parauberis that are pathogens of streptococcosis of cultured flounder, Paralichthys olivaceus, in Jeju area was examined. The result of experiments on the grow according to temperatures showed that only S. parauberis grew at 10℃, the result of hemolysis test showed that only S. iniae bacteria showed β hemolysis. Only S. parauberis were positive in VP test and HIP test, both bacteria used α-D-glucose, D-mannose, D-psicose, D-trehalose, pyruvatic acid methyl ester, and glycerol as substrates. L-lactic acid was used only S. iniae bacteria, and β-methyl-D-glucosid was used only by S. parauberis. S. iniae exhibited acute infection patten, differently S. parauberis exhibited chronic infection patten in pathogenic test.

• Journal of Aquaculture
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• v.19 no.4
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• pp.247-253
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• 2006

This study was conducted to investigate the effects of dietary supplementation of ${\beta}-1,3$ glucan on growth and immune responses in juvenile olive flounder, Paralichthys olivaceus fed the white fish meal based diets for 6 weeks. Five experimental diets supplemented with ${\beta}-1,3$ glucan at 0, 0.01, 0.025, 0.05, 0.1 % (Control, $G_{0.01},\;G_{0.025},\;G_{0.05}\;and\;G_{0.1}$, respectively) of diet on a dry-matter basis. Five experimental diets were formulated to be isonitrogenous and isocaloric to contain 50.0% crude protein and 16.7 kJ available energy $g^{-1}$. Fish averaging $3.2{\pm}0.1\;g\;(mean{\pm}SD)$ were randomly distributed in each aquarium as triplicate groups of 15 fish. Weight gain (WG, %), specific growth rate (SGR, %), and feed efficiency (FE, %) of fish fed $G_{0.1}$ diet were found significantly higher than those of fish fed Control, $G_{0.01},\;G_{0.025}\;and\;G_{0.05}$ diets (P<0.05). However, there was no significant difference among the fish fed control, $G_{0.01},\;G_{0.025}$. Chemiluminescent responses (CL) of fish fed $G_{0.1}$ diet were significantly higher than those of fish fed the other diets. Serum lysozyme activities of fish fed $G_{0.05}$ and $G_{0.1}$ diets were higher than those of fish fed control, $G_{0.025}$ and $G_{0.05}$ diets. Fish fed $G_{0.1}$ diet showed a significantly lower cumulative mortality than did fish fed control diet throughout the challenge test (P<0.05). These results suggested that based on growth rate, feed efficiency, non-specific immunity and protection against microbial infections the optimum dietary ${\beta}-1,3$ gulcan could be greater than 0.05% but less than 1.0% in juvenile olive flounder, Paralichthys oilvaceus.