• Asian-Australasian Journal of Animal Sciences
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• v.10 no.4
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• pp.439-443
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• 1997

A total of 135 freshwater fish samples (Oreochromis spp. <85> and Clarias lazera <50>) were collected from different localities (shops and fish markets) in Alexandria Province-Egypt and examined for the presence of parasitic larval stages. The obtained data found the overall mean of the infestation with encysted metacercariae was 71.1% in the examined fish. The rates of infestation with encysted metacercariae were 72.9% and 68.0% in the examined Oreochromis spp. and Clarias lazera, respectively. The highest prevalence of the encysted metacercariae was found in summer (81.8%) in case of Oreochromis spp. and in winter (92.3%) in case of Clarias lazera, all these seasonal differences are statistically significant. The rate of infestation of encysted metacercariae in the anterior third, middle third and posterior third of Oreochromis spp. was found to be 82.3%, 74.2% and 95.2%, respectively, while 88.2%, 88.2% and 91.2%, respectively, in Clarias lazera. Moreover, the rate of infestation of encysted metacercariae in eyes, gills, liver, kidney and branchial cavity of Oreochromis spp. was 91.9%, 70.9%, 20.9%, 46.8% and 32.2%, respectively. In Clarias lazera the infestation rate was found to be 47.1%, 70.6%, 8.8% and 38.2% in the gills, liver, spleen and kidney, respectively. The zoonotic and public health importance of the encysted metacercariae are causes severe visceral pain, abdominal discomfort, intermittent bloody diarrhoea and colic after consumption of inadequately cooked fish especially Tilapia spp. (Oreochromis spp.).

• Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.441-448
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• 2014

We examined the effects of dietary nutrient content, feeding period, and feed allowance on compensatory growth, food use, chemical composition, and serum chemistry of juvenile olive flounder Paralichthys olivaceus. We placed 720 juvenile fish into 24 400-L flow-through round tanks (30 fish per tank).A $2{\time}2{\time}2$ factorial design (diet: control (C) and high protein and lipid (HPL) ${\time}$ feeding period: 8 and 6 weeks ${\time}$ feed allowance: 100% and 90% of satiation) was applied. Fish were hand-fed twice daily, based on the designated feeding schedule. Weight gain and food consumption were affected by both the feeding period and feed allowance, but not by diet. The food efficiency ratio was not affected by diet, feeding period, or feed allowance, but the protein efficiency ratio and protein retention were affected by diet and feeding period, respectively. We found that the full compensatory growth of fish was not achieved at a restricted feeding allowance.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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• pp.163-170
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• 2015

Recently LED fish-attracting lamps have been more widely used in fisheries as low-cost and high-efficiency fishing gear, and development of long-life high-efficiency lamps is required through the design of LED packages to optimize heat resistance. This study developed an improved LED fish-attracting lamp with excellent heat performance, which was verified using a numerical model. Heat-resistance design factors such as the heat-radiation fin shape, PCB type, and LED chip count were investigated and optimized. Comparison with a commercial 180-W LED fishing lamp showed that the increase in initial temperature was 40% higher than that of the surrounding LED chip because of design errors in contact thermal resistance. The 250-W LED lamp developed in this study has a characteristic with thermal rising in linearly stable according to the heat source. In addition, luminance efficiency was improved by 20-65% by using flow-visualization simulation. A decrease of 45% in total power consumption with a fuel-cost reduction of over 55% can be expected when using these optimized heat release design factors.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.596-616
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• 2021

A global increase in fish consumption has led to a rapid expansion of aquaculture production, which has been linked to enhancing the spread of infectious diseases. Viral diseases can cause high mortality in many cultured fish species, posing a serious threat to the aquaculture industry. Infectious hematopoietic necrosis virus (IHNV) is one of the primary threats to aquacultured salmonid species, causing huge economic losses. Since the first report in cultured sockeye salmon Oncorhynchus nerka during the 1950s in North America, IHNV has spread to other regions, including Europe, Asia, South America, and Africa by transportation of infected fish and eggs, causing disease and increasing mortality in a wide variety of salmonid species. Here, we review existing information relevant to IHNV: its phylogenetic characteristics, origin, infection history, virulence determinants, susceptible hosts, vectors, and vaccine development. This review also addresses a possible cross-species transmission of IHNV to a new host, olive flounder Paralichthys olivaceus, a cultured fish of economic importance in East Asian countries.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.6
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• pp.918-924
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• 2020

This study investigated diurnal fasting and postprandial total ammonia nitrogen (TAN) excretion rates in juvenile Oplegnathus fasciatus (rock bream; mean body weight 45.8±1.1 g) at three temperatures (15, 20, and 25℃) in a recirculating system (three replicates). The fish were hand-fed twice daily (09:00 and 17:00 h) with commercial food (46.7% protein) until satiation. The results showed that the fasting and postprandial TAN excretion rates were temperature-dependent. The mean hourly rates were 7.7 (15℃), 10.2 (20℃), and 11.9 (25℃) mg kg fish-1 h-1 for fasting and 34.0 (15℃), 47.8 (20℃), and 60.2 (25℃) mg kg fish-1 h-1 for postprandial. At each temperature, two postprandial TAN excretion peaks were observed 2-4 h after feeding; the second peak was always higher. The TAN loss to nitrogen consumption ratio was 41.1-46.8 % and increased significantly with increasing temperature. Temperature affected fasting and postprandial TAN excretion in juvenile rock bream, providing insight for culture management.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.1
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• pp.1-7
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• 2009

The toxicity of two species of puffer fish, Takifugu poecilonotus (Heuinjeombok) and T. vermicularis (Gukmaeribok) collected from the coastal regions of Korea was determined using a mouse bioassay. In the T. poecilonotus collected in Jeju and Tongyeong, the proportion of toxic specimens containing ${\ge}10$ mouse units (MU) per gram exceeded 95% for the skin, liver, ovary, and fin, and approximately 30% for the testis and muscles. In each of the organs, the highest toxin levels were 79 MU/g in the muscle, hundreds (158-365) of MU per gram in the fin, intestine, testis, and gallbladder, but thousands (1,147-2,406) of MU per gram in the skin, liver, and ovary. In T. vermicularis collected from Incheon and Gunsan, the proportions of toxic specimens were 100% for the gallbladder, and 56-68% for the skin, fin, liver, and intestine however, no toxic muscle specimens were noted. The highest toxin scores were below 10 mouse units (MU) per gram in the muscle, 20-94 MU/g in the skin and fin, 319 MU/g in the intestine, and thousands (1,548-4,624) of MU per gram in the liver, gonad, and gallbladder. The toxicity in the muscle of T. vermicularis was deemed acceptable for human consumption, whereas the toxicities in the muscle of T. poecilonotus and the skin of both species of puffer fish were significantly high, such that special attention may be required when the fish is intended for human consumption.

• Journal of Environmental Health Sciences
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• v.42 no.3
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• pp.224-233
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• 2016

Objectives: The purpose of this study was to evaluate the relationship between residential surroundings, such as a power plant, steel mill and petrochemical facilities, and urinary arsenic concentrations in Chungcheongnam-do Province, Korea. Methods: Stratified by fish consumption and residential district, median and maximum block sampling was applied. A total of 346 spot urine samples were speciated for $As^{5+}$, $As^{3+}$, monomethylarsonic acid(MMA), dimethylarsonic acid (DMA) and arsenobetaine (AsB). Exposure assessment was based on questionnaires including data on sex, age, current tobacco use, fish consumption, type of water consumed, and occupational category. Results: Urinary $As^{5+}+As^{3+}+MMA+DMA$ concentrations of people living in the vicinity of a power plant ($GM=50.39{\mu}g/g$) were 61% higher than those of people living in the inland area according to median block sampling. Urinary $As^{5+}+As^{3+}+MMA+DMA+AsB$ concentrations of people living in the vicinity of industrial complex area were higher than those of people living in the inland area according to block sampling by median and maximum. Conclusion: Urinary arsenic concentrations of people living in vulnerable areas such as around industrial complexes, especially power plants, were higher than those of people living in an inland area.

• The Journal of Fisheries Business Administration
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• v.46 no.3
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• pp.119-127
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• 2015

This study is to analyse the causality and volatility spillover between farming fish species in consumption replacement relation using flatfish(oliver flounder) and rockfish's wholesale market price data from September 2006 to July 2015. For the analysis, VAR(5) model and bivariate asymmetric GARCH-BEKK model are employed. The empirical results of this study are summarized as follows: First, the price volatility of flatfish and rockfish is very large without the trend during the sample period. Second, the correlation coefficient between flatfish and rockfish wholesale markets has positive 0.1059 value. Third, causality relation is unidirectional from rockfish market to flatfish market. Fourth, conditional volatility spillover effect is unidirectional from rockfish market to flatfish market, but asymmetric volatility effect is bidirectional between flatfish and rockfish markets that implies the bad news arising from flatfish wholesale market impact on rockfish market's volatility and the bad news arising from rockfish wholesale market impact on flatfish market's volaltilty. Consequently, based on the thus results, the volatility spillover effect interacts and is bidirectional between flatfish and rockfish wholesale markets.

• The Journal of Fisheries Business Administration
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• v.50 no.3
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• pp.17-29
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• 2019

This paper aims to find out the problems and improvement direction of quality control and hygiene management of fishery products in Korea. For this reason, we conducted a comparative analysis of quality control and hygiene management of fishing, landing and selling between Japan and Korea, taking mackerel as an example. Japan has established a systematic freshness management system from fishing to landing (production) areas and consumption areas. On the other hand, Korea is not fully lead-managed in the production area after fishing, and is distributed in a state where the quality of the product is deteriorated due to exposure to room temperature. Accordingly, a certain quality can not be secured at the final consumption stage, and sanitary problems occur. In order to improve the quality control and hygiene management of the fishery products, the following needs to be improved. First, we will improve the fishing level freshness management system. Second, we will improve the quality control and hygiene management of fish in the production area and wholesale stage. Third, we will promote the introduction of innovative sales and consignment sales systems at the production stage. Fourth, we will establish a consistent low temperature distribution system from the production area to the wholesale stage from a long-term perspective. Fifth, we will promote the development and education of manuals on fish quality and hygiene management.

• Journal of the Korean Society of Food Culture
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• v.34 no.1
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• pp.1-13
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• 2019

This study was conducted to track the appearance of Aguijjim and its popularity on the national level. Furthermore, changes in the monkfish recipe and how they impacted the consumption of monkfish were investigated. It is assumed that monkfish was consumed by Japanese in Korea during the Japanese colonial era. After liberation, people cooked the fish as soup. In the 1960s, Aguijjim was invented in Masan. There is great controversy regarding how the dish was born. It has been asserted that it was created by one specific person, that refugees with insufficient food developed, and that it is just an advancement of Bugeojjim. Aguijjim restaurants began to appear in Seoul in the 1970s, and in the 1990s streets full of Aguijjim restaurants formed. Moreover, popular music and literature referenced Aguijjim in the late 1990s. As Aguijjim has developed and the formation of Aguijjim street have combined, the consumption of monkfish has increased drastically, leading to its import. As cooking methods have transformed, the fish with the unpleasant look which was thrown out in the past, have dramatically gained public interest. 'Masan Aguijjim' became an independent brand that represents a local food that has also been nationalized in a short amount of time.