• Journal of Fisheries and Marine Sciences Education
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• v.21 no.3
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• pp.451-458
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• 2009

The purpose of this study is to analyze the nutrition composition and physiological changes, and to evaluate the food quality of live fish in cultured and wild fishes which have been kept in an aquarium tank. The moisture and lipid content of wild and cultured fishes when kept in an aquarium tank for seven-days storage was found to be lower than those of the initial stage storage(zero day). The breaking strength was also rapidly decreased in all of live fishes tested in this study as the periods of storage extended. The protein content did not differ significantly. However, the content of cortisol, which is a indicator indicating a stress reaction in tissues, was apt to increasing as the periods of storage extended. The cortisol content of wild fishes were higher than those of cultured fishes. On the other hand, the activity of activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), which is also a indicator indicating a stress reaction, were not changed in the serum of wild and cultured fish, suggesting the ALT and AST activity dose not directly related with a healthy loss originated from stress. The death ratio of wild fishes were higher than cultured ones due to limited activity and stress during the storage in a aquarium tank.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.95-98
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• 2013

The experiment was conducted to determine the value of black soldier fly (Hermetia illucens) larvae and pupae as feed supplements for fresh-water fish (Carassius auratus). Black soldier fly larvae grown on food waste were fed to fresh-water fish, live larvae alone, dried larvae, dried pupae and combination with commercial fish diet. A 16-week feed trial was conducted to determine whether black soldier fly larvae could be used as a feed supplement in fresh-water fish. The growth performance indicated that fish fed the live larvae ranked consistently higher, and in combination with commercial fish diet and dried larvae and pupae were next higher. The finding of this study suggest that black soldier fly larvae and pupae may be valuable feedstuff in commercial fish production.

• Fisheries and Aquatic Sciences
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• v.7 no.4
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• pp.192-203
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• 2004

The effects of temperatures, starvation, and kind of foods on growth, RNA/DNA ratio and protein contents during metamorphosis and early juvenile stage of olive flounder (Paralichthys olivaceus) were examined. During metamorphosis, warm-acclimated fish showed higher RNA and DNA content than those of the cold-acclimated fish, excepting H stage (28 DAH) at which the ratio was higher at cold temperature. RNA/DNA ratio during metamorphosis showed similar values at two temperatures tested. However, after 42 DAH warm-acclimated juveniles had higher DNA content compared with cold-acclimated fish, resulted in marked decreases in RNA/DNA ratios. Higher RNA content at H stage of cold-acclimated fish was consistent with an increase in protein content. Growth of fish rearing at warm temperature was higher than those of fish at cold temperature during all experiments. In starvation experiment, contents of DNA, RNA and protein significantly decreased. Even though there were no significant differences in total length (TL) and body weight between the live mysid-fed and artificial pellet-fed fish at 35 mm TL, both RNA/DNA and protein/DNA ratios of the former group was significantly higher than those of the latter due primarily to lower DNA content of the live mysid-fed group. The results from this study suggest that temperature, starvation and kind of foods should be considered when RNA/DNA ratio applied to assessing the cultured larval and juvenile fish condition.

• The Journal of Fisheries Business Administration
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• v.45 no.3
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• pp.99-110
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• 2014

Flounder was selected as one of the 10 strategic export aquaculture products for seafood export expansion in 2013. The flounder aquaculture industry has promoted export market diversification and product diversification from live to processed goods as a it's main strategy. The purpose of this study is to find an improvement plan for export expansion to the United States, as it emerged as a new target export market for the flounder. A summary of the key findings is as follows. First, the western region of the United States prefers to consume live and fresh flounder, whereas the eastern region prefers to consume fresh flounder. Second, because of it's high quality, Korean flounder is favored in the western region of the United States despite it's high price, whereas in the eastern region of the United States, where production volume is high, Korean flounder has to compete with US flounders because of it's high price. Third, according to the survey results, US consumers tend to enjoy seafood, as well as flounder cuisines. Fourth, the main consumption place of flounders by US consumers are restaurants, and they prefer to consume them in the form of sashimi and sushi. Fifth, 70% of US consumers expressed willingness to consume flounder when eating out. which shows great market potential. However, the high price of Korean flounder and limited size of the live fish market act as major obstacles to expanding export volume. To expand exporting Korean flounder, continuos efforts such as price reduction, exporting highly fresh fish, the co-development of processed food with the US are needed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.2
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• pp.195-206
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• 2017

Joint time-frequency images of the broadband echo signals of six fish species were obtained using the smoothed pseudo-Wigner-Ville distribution in controlled environments. Affine transformation and principal component analysis were used to obtain eigenimages that provided species-specific acoustic features for each of the six fish species. The echo images of an unknown fish species, acquired in real time and in a fully automated fashion, were identified by finding the smallest Euclidean or Mahalanobis distance between each combination of weight matrices of the test image of the fish species to be identified and of the eigenimage classes of each of six fish species in the training set. The experimental results showed that the Mahalanobis classifier performed better than the Euclidean classifier in identifying both single- and mixed-species groups of all species assessed.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.241-246
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• 2001

Distribution of pathogenic vibrios in the seawater of live fish tank and effect of environmental factors on their existence were investigated by collecting samples from fish markets and restaurants in 6 different cities. Pathogenic vibrios and coliforms were determined by using the most probable number (MPN) procedure, and aerobic plate count was enumerated by the standard pour plate method. No Vibrio chulerae O1 was detected in all the samples tested. Detection rates of V. cholerae non-O1, V. parahaemolyticus and V. vulnificus in all the smaples tested were 7.7%, 69.2% and 23.1%, respectively. Water temperature and trubidity of the seawater measured were higher in the pathogenic vibrios positive samples than in those negative samples. However, higher salinity and pH were shown in the pathogenic vibrios negative samples than in positive samples. The aerobic plate counts and MPN or total and focal coliforms in the seawater were higher in the presence of pathogenic vibrios than in the absence of pathogenic vibrios. In this study, the presence of pathogenic vibrios in the seawater tested was closely related with other physiochemical parameters and populations of coliforms, indicators far food safety.

• Journal of fish pathology
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• v.31 no.2
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• pp.93-99
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• 2018

Edwardsiella tarda predominantly causes edwardsiellosis in fish at high temperature, but is rarely isolated from water when water temperature is low. However, E. tarda is viable but nonculturable (VBNC) in low water temperature, but it can be revived when water temperature rises and cause disease to fish. Therefore, in order to prevent disease, it is very important to identify pathogens that are in the VBNC state in environmental water. In this study, E. tarda cells in the VBNC state were detected by the ethidium monoazide (EMA)-PCR method using the low-temperature oligotrophic sea water microcosm obtained by inoculation of E. tarda at a concentration of $10^8CFU/ml$. In order to distinguish between live and dead bacteria in E. tarda, each sample was treated with EMA at different concentrations, photoactivated with a 500 W halogen lamp, and PCR was performed with E. tarda specific primer. At the concentration of $10^7CFU/ml$ bacterium, DNA amplification was observed only in the live cells when treated with $60{\mu}g/ml$ of EMA, and smaller amounts of live cells could be distinguished from dead cells by adjusting the EMA concentration. In addition, the VBNC cells of E. tarda in the oligotrophic low temperature seawater microcosm were estimated to be in the range of $10^4{\sim}10^5CFU/ml$ by EMA-PCR. Therefore, it is possible to detect VBNC cells that will act as potential pathogens in environmental water using EMA-PCR method, and quantitative confirmation using concentration change is also possible.

• Journal of Industrial Technology
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• v.26 no.B
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• pp.63-71
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• 2006

The concerned object of the construction industry is environment. It is one of the main purposes of today's construction that human can live reasonably in nature. This study is about the fish-road connecting hydraulic structure in the river with nature. Chapter 2, starting with the general investigation about fish-road and helps comprehension for relatively general fish-road such as necessity, establishment purpose, history, study example, relating domestic law, design condition, consideration and form of fish-road. Chapter 3, containing the present condition of fish-road facilities in Gangwon-Do and thoughts of the problems and general countermeasures of existing fish-road. Chapter 4, Having Examined compatibility by amount of flowing water through hydraulic model test in the Ice harbor I-type model. chapter 5, Analyzation and arrangement to efficient establishment plan of fish-road and the result of the hydraulic model experiment to be beaconed a little in forward fish-road study. In the hydraulic model test result, when we suppose establishment of 1~3 in slope of 1/20, could know that applicable drought flow of the river is $0.06{\sim}3.0m^3/sec$ in case of Ice harbor I-type which transforming Ice harbor that was invented as studying project of the Ministry of Environment.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1324-1329
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• 2001

The depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. This study represents the thermal characteristics of the fish hold storage during transportation. The numerical analysis in this study is the finite volume method with the SIMPLE computational algorithm to study the seawater flow behavior in the fish hold storage. The computation were carried out with the variations of the circulating flow velocity and depth of fish hold storage. As the result of the three dimensional simulations, the mean temperature doesn't almost change by the circulating flow rate. find the mean temperature is suddenly changed by the ratio of depth of fish hold storage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.342-347
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• 2002

Ciliates have the possibility of a new live food in marine finfish culture because of their wide range of body size, thin tell wall, show motility, and fast reproduction rate. In this research, six species of ciliates were isolated from south coast and salt pond in Korea. The fitness of these species as a live food was evaluated in terms of size, motility, suspensibility and cell density. As the result, Euplotes sp. (K-1) was found suitable to be a new live food which might substitute rotifers, Brachionus plintilis and B. rotundiformis in fish larvae culture. The modified $F{\emptyset}yn's$ Erdschreiberd media, MErds-2 with the addition of glycine, glucose and yeast extract increased six times higher growth rate of Euplotes sp. (K-1) than the basic F$\emptyset$yn's Erdschreiberd media. The optimum water temperature, pH and light intensity for this ciliates were $22.5^{\circ}C$, 8 and 2,000 lux, respectively, and its culture environmental range was relatively wide, On the other hand, this ciliate fed baker's yeast, Saccharomyces cererisiae grew up to 1,240 inds./mL with the inocula of 100 inds./mL within 7 days. The results of the study showed that Euplotes sp. (K-1) has a potential to be utilized as a new live food in fish larvae culture.