• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1610-1618
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• 2015

This study is aimed to estimate price interactions between wild caught fish and farmed fish on the Korean seafood market, using multivariate cointegration analysis. Major commercially important four wild caught fish (chub mackerel, hairtail, yellow croaker and spanish mackerel) and two farmed fish(oliver flounder and black rockfish) are selected as analytical target fish species. Between 2000 and 2013, monthly production and price data are used in this study. The results of cointegration test showed that there would be a long-term equilibrium relationship among 4 wild caught fish and 2 farmed fish. However, the results of exclusion test indicated that farmed fish might not contribute significantly to the long-run relationship, suggesting that farmed fish might be only a weak substitute for wild caught fish, but no significant interaction could be found.

• Journal of fish pathology
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• v.1 no.2
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• pp.123-130
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• 1988

General anaesthetics have been usually used for a long time because handling and transportation of live fish constitutes an important aspect in fisheries science. Numerous investigations, however, have shown that the majority of fish anaesthetics cause strong toxic effect to marine fishes. Therefore, less toxic and more effective anaesthetics are essential for marine fishes. Lidocaine belongs to a group of anaesthetics which are used as a local anaesthetic in human medicine. This chemical was tested for 11 commercially important marine fishes. Anaesthetic effects were clearly dose dependent and acute or chronic toxicities were not observed within clinical doses. The recovery time in the tested fish after anaesthetization was 3 to 4 minutes.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.12
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• pp.1769-1775
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• 2006

An eight week feeding trial was conducted to investigate the effects of dietary supplementation of hizikia (Hizikia fusiformis) on growth performance, immune responses and resistance of juvenile olive flounder (Paralichthys olivaceus) to Streptococcus iniae. Four experimental diets (designated as Hiz 0, Hiz 2, Hiz 4 and Hiz 6) were formulated to be isonitrogenous (50% crude protein) and isocaloric (17.2 MJ/kg DM). Hizikia powder was added at 0%, 2%, 4% and 6% in diets Hiz 0, Hiz 2, Hiz 4 and Hiz 6, respectively. Three replicates of fish groups (15 fish/tank) were fed one of the experimental diets. At the end of feeding trial, no significant differences were observed in final body weight, specific growth rate, protein efficiency ratio, feed utilization and feed intake among fish groups fed the experimental diets. However, there was clear trend that the growth performances of fish were improved by the increment of dietary hizikia showing a positive growth effects. Mean phagocytes activated with nitro-blue-tetrazolium were significantly increased with the increment of dietary hizikia. The cumulative mortality was significantly (p<0.05) lower in the fish groups fed Hiz 6 diet (no mortality) than that in the other fish groups for 15 days of S. iniae challenge test. The findings of this study suggest that a dietary supplementation of hizikia could enhance the nonspecific immune response and improve the resistance of juvenile olive flounder to S. iniae.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.2
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• pp.139-147
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• 2010

This study monitored a variety of marine fish communities in artificial reefs unit of the total 5 types (Dice type, Octagonal turtle type, Two-stage tube type, Gazebo type, Tetrapod type) which are located in the marine ranching at Jeju island by scuba diving in May, July, October and December 2009. Underwater photographing was accomplished at total 3 phases (condition of artificial reefs photographing, concentric circle movement photographing and line transect photographing). The preservation condition of artificial reefs facility was very good, and the dominant species were Chromis notatus, Sebastes thompsoni, Oplegnathus fasciatus and Halichoeres poecilopterus. Fish abundance was high in May and June, and low in October and December, 2009. Chromis notatus was dominant at the all types of artificial reefs, Halichoeres poecilopterus for Gazebo type and Tetrapod type of artificial reefs, and Sebastes thompsoni for Dice type, Octagonal turtle type and Two-stage tube type of artificial reefs.

• Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.240-255
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• 2024

Widas Reservoir is situated in an area of 570 ha in the Pajaran Village, Madiun Regency, East Java Province, Indonesia, playing an essential role in fisheries, with the average fish catch per year of about 283 tons/year. This study explores the standing stock, growth parameters, mortality, and exploitation rates of several dominant fishes in Widas Reservoir. This study was carried out from February to November 2019. Fish stocks were estimated using acoustic tools, fish catch records, and sizes collected by local enumerators. Fish length frequency sampling was conducted on several dominant fish species, such as Oreochromis niloticus, Barbonymus gonionotus, and Osteochilus vittatus. Based on the length-frequency data, estimating fish population dynamics, the fish population dynamics (infinitive length (L_∞) and growth coefficient (K)) estimation was run in a time series using the Fish Sock Analysis Tool, II (FISAT II) program package. Moreover, the estimation of natural mortality parameters, the fishing mortality parameter, and the exploitation rate was also performed. The approximated overall fish stock in the Widas Reservoir was about 79,848 kg, which lowered with the increase in water depth. Of particular concern, in the surface layer at a depth between 1-5 m, the fish stock reached 58,813 kg, while in the deeper zone (> 15 m), the value significantly lowered by about 98%, reaching 1,219 kg. These results indicate an overfishing in the Widas Reservoir. The value of the exploitation rate (E) of B. gonionotus was 0.748, O. niloticus 0.8, and O. vittatus 0.7, respectively, proving the overfishing states occurred in the study area. Therefore, regulations governing the number of catches and the use of fishing gear are crucial in Widas Reservoir, particularly the use of lift and gill nets with a mesh size of less than 2 cm.

• Journal of Nutrition and Health
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• v.29 no.5
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• pp.499-506
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• 1996

It has been established that hypercholesterolemia is a major risk factor for atherosclerosis. Recent data showed that the incidence of hypercholesterolemia increase in Korea. n-3 Fatty acids lower serum triglyceride profoundly but the effect on serum cholesterol is not clear. This study was performed to assess the effects of low and moderate supplementation of marine n-3 fatty fish on serum cholesterol in young healthy korean woman. Nineteen subjects were divided into two groups. Each group receive an experimental diet supplemented with either 100g (group I) or 200g mackeral(Scomber japonicus) fish(group II) for 1-week. The diet was designed to avoid in which the amount of n-6 fatty acids would be much greater than that of n-3 fatty acids. MUFA, SFA intakes were similar in the two diets. The ratio of n-6/n-3 fatty acids was 1 : 1.l for group I, 1 : 2.51 for group II. The average daily n-3 fatty acids consumption from fish was 3.87g/day (1.03g EPA, 2.84g DHA)for group I, 7.74g/day (2.06g EPA, 5.68g DHA) for group II. Blood samples were obtained 2 times before experimental diet, immediately after experimental diet for 1-week. After experimental diet for 1-week, the serum total-cholesterol levels decreased significantly (16.4$\pm$15.1mg/dl, p<0.01) in group II and lowered slightly (13.7$\pm$25.8mg/dl)in group I. There were no significant changes from baseline to the end of the study in serum HDL-cholesteol, LDL-cholesterol, HDL-C/T-C ratio, and LDC-C/HDL-C ratio. The results suggest that the moderate levels of marine n-3 fatty fish consumption could improve serum cholesterol in normal subjects, therefore in might be of value in the prevention of atherosclerosis. However the clinical usefulness of moderate n-3 fatty fish consumption of hypercholesterolemic subjects will require further study. Also further studies are required to elucidate the long-term effects of low n-3 fatty fish consumtion.

• Korean Journal of Ichthyology
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• v.27 no.3
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• pp.183-188
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• 2015

Recently, mariculture of rainbow trout (Oncorhynchus mykiss) has been initiated in the coast areas of Korea. In the present study, we investigated the effect of fish viruses on mariculture of rainbow trout. The pathogenicity of infectious hematopoietic necrosis virus (IHNV) and infectious pancreatic necrosis virus (IPNV) isolated from freshwater rainbow trout was tested against major cultured marine fish species, including olive flounder (Paralichtys olivaceus), rock fish (Sebastes schlegeli), rock bream (Oplegnathus fasciatus), red seabream (Pagrus major) and sevenband grouper (Epinephelus septemfasciatus). The pathogenicity of marine birnavirus (MABV), hirame rhabdovirus (HIRRV) and nervous necrosis virus (NNV) isolated from marine fish species was also tested against rainbow trout. No mortality was observed in marine fish species challenged with IHNV or IPNV. However, olive flounder and rock bream were infected by IHNV and IPNV. A mortality of 8.3% was observed in rainbow trout challenged with HIRRV. The fish was infected by both MABV and NNV. These results suggest that the mariculture of rainbow trout might be affected by fish viruses.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.683-688
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• 2016

The effects of dietary supplementing natural additives [yacon (YC), ginger (GG), and blueberry (BB)] on growth, feed utilization, and body composition of juvenile rockfish were compared to those of ethoxyquin (EQ), which is commonly used to prevent rancidity of fish feed. A total of 480 fish were distributed randomly into 12 50-L flow-through tanks (40 fish/tank). Four experimental diets were prepared: the control diet (Con) with 0.01% EQ, and the YC, GG and BB diets containing 1% YC, GG, and BB instead of wheat flour. Each diet was assigned randomly to triplicate tanks of fish, which were hand fed to satiation twice daily for 8 weeks. Weight gain of fish fed the YC diet was higher than that of fish fed all other diets. Feed efficiency (FE), protein efficiency ratio (PER), and protein retention (PR) in fish fed the YC diet were higher than those in fish fed the other diets. Whole-body chemical composition of the fish was affected by the additive sources. In conclusion, dietary supplementation with GG effectively improved weight gain and feed utilization (FE, PER, and PR) of juvenile rockfish.

• Journal of fish pathology
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• v.34 no.1
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• pp.55-61
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• 2021

One of the major problems in fish production is that parasite-induced episodes of disease can result in significant impacts to the health of stock, mortalities and, economical losses. Seabreams are economically important fish in both the capture fishery and aquaculture sectors in Oman and represent potential species for aquaculture. The current study set out to investigate infection of polyopisthocotylean monogeneans on the gills of wild goldlined seabream, Rhabdosargus sarba, caught from Musairah region in Oman. The prevalence, mean intensity and abundance of polyopisthocotyleans on 145 fish was found to be 52.41%, 5.65 and 3.04, respectively. Three species of microcotylid parasite were isolated, one being Atrispinum acarne while the remaining two species require further study to identify them. There was no significant difference in the infection rate between host sex, however, parasite burdens were higher on larger sized fish (p<0.05) and were found to favour the first gill arch (p< 0.05). The study found that the sample of Rhabdosargus sarba landed in the waters around Musairah are heavily infected, with a predominantly immature population of microcotylids. Further work is required to better understand the potential risk each species poses to the health of its host before a decision is made on the suitability of new candidate fish species for commercial aquaculture.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.90-96
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• 2013

Effects of dietary Scutellaria baicalensis extract (SBE) on growth, feed utilization and challenge test of olive flounder (Paralichthys olivaceus) were determined. Six hundred thirty fish averaging 5.0 g were distributed into 18, 180-L tanks. Six experimental diets were prepared in triplicate: SBE-0, SBE-0.5, SBE-1, SBE-2, SBE-3 and SBE-5 diets containing SBE at the concentrations of 0, 0.5, 1, 2, 3 and 5%, respectively. Fish were hand-fed to apparent satiation twice a day for 8 wks. At the end of 8-wk feeding trial, ten fish from each tank were infected by Edwardsiella tarda for challenge test. Survival and weight gain of fish were not affected by dietary concentrations of SBE. However, specific growth rate of fish fed the SBE-2 diet was higher than that of fish fed the SBE-0, SBE-1, SBE-3 and SBE-5 diets. Neither feed efficiency nor serum chemical composition of fish was affected by dietary concentrations of SBE. The cumulative mortality of fish fed the SBE-0 diet was 100% at 96 h after E. tarda infection, but 77 to 87% for fish fed the other diets. Dietary inclusion of 2% SBE appears to be recommendable to improve specific growth rate of fish and SBE had the potential to mitigate mortality of fish at E. tarda infection.