• 한국어병학회지
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• 제22권2호
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• pp.163-166
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• 2009

The ectoparasite ciliate Trichodina has been recorded from above 100 species of freshwater and marine fishes. In April 2009, we investigated the trichodia infection in 13 species of marine fishes captured by emplacement net and gill net in order to understand trichodina infection status among the natural fish populations along the Namhae-Gun coast area, the southen coast of Korea. Trichodina infection was observed in 10 out of 10 sea basses Lateolabrax japonicus, 2 out of 5 finespotted flounder Pleuronichthys cornutus and 1 out of a stone flounder Kareius bicoloratus. The sea bass infected with the parasite showed hypertrophy and exfoliation in gill epithelium. In addition, hyperplasia and lamellar fusion of gill filament were noticed among naturally affected sea bass.

• Mycobiology
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• 제50권5호
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• pp.326-344
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• 2022

The fungal-like family Saprolegniaceae (Oomycota), also called "water mold," includes mostly aquatic saprophytes as well as notorious aquatic animal pathogens. Most studies on Saprolegniaceae have been biased toward pathogenic species that are important to aquaculture rather than saprotrophic species, despite the latter's crucial roles in carbon cycling of freshwater ecosystems. Few attempts have been made to study the diversity and ecology of Saprolegniaceae; thus, their ecological role is not well-known. During a survey of oomycetes between 2016 and 2021, we investigated the diversity and distribution of culturable Saprolegniaceae species in freshwater ecosystems of Korea. In the present study, members of Saprolegniaceae were isolated and identified at species level based on their cultural, morphological, and molecular phylogenetic analyses. Furthermore, substrate preference and seasonal dynamics for each were examined. Most of the species were previously reported as animal pathogens; however, in the present study, they were often isolated from other freshwater substrates, such as plant debris, algae, water, and soil sediment. The relative abundance of Saprolegniaceae was higher in the cold to cool season than that in the warm to hot season of Korea. This study enhances our understanding of the diversity and ecological attributes of Saprolegniaceae in freshwater ecosystems.

• 한국어병학회지
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• 제22권3호
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• pp.211-218
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• 2009

경북 울진 지역에서 채집된 양식 강도다리와 충남 태안 및 부산 지역 넙치 시료로부터 분리한 MABV에 대한 유전자 비교를 위해 VP2-NSPhylogenetic VP3 region (432 bp)을 phylogenetic 분석에 이용했다. Sequence 확인 결과 MABV (08-KU)는 일본 방어에서 최초 분리 보고된 YTAV와 98%의 nucleotide 유사성이 나타났으며, 이전 보고된 다 른 여러 strain들과는 76%이상 유사한 것으로 확인되었다. 그리고 MABV (06-KP)와 MABV (08-KC)도 YTAV와 97-98%의 높은 sequence 유사성을 보였다. 또한 다양한 MABV strain들과의 비교를 위해 충남태안 및 부산지역 넙치 시료에서 분리한 MABV (08-KC)와 MABV (06-KP)에 대한 phylogenetic 분석도 실시하였다. 그 결과 분석에 사용된 MABV (08-KU0, MABV (06-KP), MABV (08-KC)는 모두 일본 방어에서 분리된 MABV Y6와 동일한 genogroup VII에 포함 되었다.

• 한국어병학회지
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• 제22권3호
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• pp.317-326
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• 2009

This study has shown the screening of anti-bacterial activity of three Indian medicinal plant choloroform : methanol (50:50) solvent leaf extracts (i.e. Azadirachta indica, Ocimum sanctum, and Curcuma longa) with different concentrations (10, 5, 2.5, 1.25, 0.625, 0.312, and 0.156 mg/ml) under in vitro conditions against fish pathogenic bacteria, Aeromonas hydrophila, Streptococcus iniae, Vibrio harveyi, V. anguillarum, and Edwardsiella tarda isolated from olive flounder farms, Jeju Island, South Korea. The anti-microbial activity of the A. indica and O. sanctum extracts yielded the zones of growth inhibition (ZI) was 3 and 1mm against A. hydrophila at concentration of 0.156 mg/ml when compared to that of tetracycline standard (3 mm). At highest concentration (10 mg/ml) of A. indica, O. sanctum, and C. longa, high inhibition was 9, 7, and 6 mm when compared to that of tetracycline (11 mm) against A. hydrophila. The minimum inhibitory concentration (MIC) of A. indica, O. sanctum, and C. longa at 0.156 mg/ml that yield 9, 10, and 13 CFU/ml for A. hydrophila, 16, 22, and 25 CFU/ml for S. iniae and 18, 22, and 23 CFU/ml for E. tarda compared to the tetracycline. At highest concentration (10 mg/ml) of the three extracts was better inhibiting the growth of A. hydrophila, S. iniae and E. tarda. A. indica, O. sanctum, and C. longa were determined to the potential antioxidant activityon the basis of their scavenging activity of the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. A. indica extract was 0.625 mg/ml which indicated that the strong anti-oxidant activity. However, O. sanctum and C. longa extracts showed weak anti-oxidant activity at this concentration. Hence, in vitro assay among the pathogens, A. hydropila is better inhibitory activity of the extracts. It is evident that the Indian medicinal plants extracts were subjected to its effectiveness against A. hydrophila, S. iniae, and E.tarda at low concentrations. The obtained results in the present study suggested that the Indian plant extracts is a prevention tools for Korean olive flounder aquaculture pathogens and its need further advance investigation.

• 한국식품위생안전성학회지
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• 제5권3호
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• pp.139-158
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• 1990

동물성 식품의 생산을 증가시키기 위하여 다양한 종류의 ehdafn성 약물이 사용되고 있고 공업의 발달과 더불어 각종의 공해물질이 수질과 토양을 오염시키고 있다. 따라서 이와 같은 화학물질이 직접 혹은 간접적으로 동물성 식품을 오염시키거나 식품에 잔류할 가능성이 높아지고 있다. 이에 따라 농림수산부와 보건 사회부에서는 약제 잔류를 방지하기 위하여 잔류 허용기준을 따로이 마련하였고 독자적으로 잔류에 대한 조사연구에 착수하였다. 잔류 약제에 대한 규제는 국민건강을 지킨다는 의미에서 착실히 추진되어야 할 것이나 생산기반이 흔들리지 않는 범위 내에서 점진적으로 진행되어야 할 것이고, 국내에서의 동물성 식품의 안전성 확보를 통하여 수출을 확대하고 무분별한 수입을 억제할 수 있도록 이원화되어 있는 업무를 일원화되어야 한다. 검사를 통하여 잔류를 방지하고자 하는 정책 보다는 생산 단계에서 안전휴약기간을 지키도록 적극 교육, 홍보, 지도하여야 한다. 이 심포지엄 연제에서는 미국과 한국 농림수산부에서는 잔류검사기법에 대한 개요와 검사 계획, 국내에서의 잔류물질에 대한 조사연구 개황, 그리고 허용기준 설정방법 등에 대하여 논의한다.

• 한국수산과학회지
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• 제52권2호
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• pp.134-140
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• 2019

A feeding trial was conducted to investigate the effects of dietary fish meal replacement by a blend of lysine cell mass, corn protein concentrate and poultry by-product meal on the growth and blood chemistry of the starry flounder Platichthys stellatus. The fish meal replacer (FMR) was prepared to have the same level of protein as fish meal (FM). With a commercial diet as a positive control, five experimental diets (basal, FM42, FM32, FM22 and FM12) were formulated to contain 52% protein and 10% lipid. The dietary FM levels decreased from 52% (basal) to 42, 32, 22 and 12% with concomitant increase in the FMR to 10, 20, 30, 40 and 50%, respectively. Juvenile starry flounder with an average body weight of 177.3 g were randomly distributed in each (30 fish/tank) of 18 plastic tanks ($139{\times}99{\times}54cm$). After a 45-day feeding trial, the survival rate ranged from 95.6% (FM22) to 100% (control and FM42), while the weight gain of the fish groups varied from 49.7 to 58.4 g. The results clearly revealed that starry flounder can grow well on a diet containing low FM (12%) with a high level of FMR (50%) without any adverse effects.

• 한국어병학회지
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• 제35권2호
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• pp.205-214
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• 2022

In recent years, there have been many studies investigating changes in animal behavior using video tracking technology to track motion. However, there have been very few studies and results on changes in the behavior of fish infected with a pathogen. Therefore, the present study attempted to analyze the behavior of angelfish (Pterophyllum scalare) infected with bacterial pathogens using video tracking. Two cameras were placed in front of the water tank to obtain behavior data, and tracking was performed for three days until the day of death. Data such as average speed, changes in speed, the locations of the fish in the tank, and fractal dimension were statistically analyzed based on the fish speed and location in the tank of the fish. For bacterial infection, an individual angelfish was intraperitoneally injected with approximately 10⁶ CFU ml^-1 of Aeromonas hydrophila or Edwardsiella piscicida. The experiment was carried out five times for each group. Fish infected with the bacterial pathogens showed a tendency to increase in speed and to spend more time in the upper part of the tank one or two days before death. On the day the fish died, the average speed, changes in speed, and the fractal dimension value were significantly lower than the corresponding values in the control group, and the fish also remained in the lower part of the tank. Our results indicated that behavioral changes in fish could be successfully detected earlier than death using video tracking technology, and that this method presents potential for disease monitoring in aquaculture.

• 한국어병학회지
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• 제24권2호
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• pp.121-129
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• 2011

배양장에서 생산된 양식생물은 자원조성에 필요한 종묘를 제공한다는 측면에서 매우 중요한 역할을 담당하고 있으며, 방류종묘의 질, 특히 개체의 건강도 는 방류이후 서식처에서 생존하고 자원조성 효과를 결정짓는데 매우 중요한 요소가 된다. 2010년도 방류 품종(해면품종 33종과 내수면품종 12품종)을 대상으로 수산동물전염병의 감염 여부를 검사하였다. 검사 품종 중에서 해면품종으로는 전복이 20.0%로 가장 많았으며, 그 다음 해삼(15.6%), 넙치(8.4%), 조피볼락(6.7%), 감성돔(6.3%), 꽃게(6.1%) 순으로 나타났다. 내수면품종 중에서는 붕어가 19.4%로 가장 많았으며, 그 다음으로 뱀장어(11.8%), 동자개(10.9%), 쏘가리(10.8%), 다슬기(8.4%), 메기(7.7%)의 순으로 나타났다. 총 45개 품종을 대상으로 1,120회의 검사가 의뢰되었으며, 검사 항목별로 2,105건의 검사를 실시한 결과 30건에서 koi herpesvirus (KHV), red sea bream iridovirus (RSIV), white spot syndrome virus (WSSV) 또는 viral haemorrhagic septicemia virus (VHSV)와 같은 병원체가 검출되어 불합격 처리되었다.

• 한국수산과학회지
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• 제49권3호
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• pp.270-276
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• 2016

This study investigated the sensory characteristics (texture, odor, taste and color) of jerky produced from ground sea rainbow trout (SRT) Oncorhynchus mykiss frame muscle (FM). The hardness of the ground SRT-FM jerky was 453.9±91.0 g/cm², which was lower than that of commercial animal jerky (893.5±404.6 g/cm²) and commercial fish jerky (1,394.4±363.5 g/cm²). The difference in the hardness values of the ground SRT-FM jerky and commercial animal jerky was not significant. The volatile basic nitrogen content of the ground SRT-FM jerky was 48.3±1.6 mg/100 g, which was higher than that of commercial fish jerky (21.6±6.2 mg/100 g) and commercial animal jerky (18.2±6.3 mg/100 g). However, the fish odor of the ground SRT-FM jerky was masked by the presence of various additives. The hydrophilic and lipophilic browning indices of the ground SRT-FM jerky were higher than those of the commercial jerky. The total taste value of the ground SRT-FM jerky was 169.0, and the major amino acids were glutamic acid and aspartic acid. These results suggest that ground SRT-FM jerky would be acceptable to consumers.

• 한국수산과학회지
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• 제54권3호
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• pp.350-357
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• 2021

This study aimed to evaluate how fish meal (FM) replacement in diets with a mixture of animal and plant protein sources affect growth performance, feed utilization, hematological parameters and innate immunity of red seabream Pagrus major. A control FM diet was formulated to contain 65% FM (Con). Two other diets were prepared replacing FM in the control diet with a mixture of protein sources (wheat gluten, soy-protein concentrate, tankage meal, and poultry by-product meal) by 30 and 40% (FM30 and FM40, respectively). Total 300 red seabream (body weight, 77.6±0.3g) were distributed to 12 tanks (300 L) in 4 replicates per diet. The fish were fed the diets to apparent satiation for 19 weeks. After the feeding trial, no significant differences could be observed in growth performance, feed utilization, hematological parameters, innate immunity, and survivals among all the dietary treatments. This long-term feeding trial at low water temperature (13.8-17.5℃) indicates that a proper mixture ratio of wheat gluten, soy protein concentrate, tankage meal, and poultry by-product meal can replace FM up to 40% in red seabream diets.