• 한국해양학회지
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• v.21 no.2
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• pp.85-91
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• 1986

Diet and feeding patterns of 10 species of gonostomatid fish in the Rockall Trough and Porcupine Seabight, northeastern Atlantic, were investigated as a part of studies analyzing the meso-and upper bathypelagic micronektonic fish communities in these two areas. Copepods were the major food organisms, composing more than 72% in both areas, and ostracods the second most abundant prey organisms (〉13%). The results of stomach content analyses reveals that most of gonostomatids, including two important species, Cyclothone braueri and C. microdon, feed continuously regardless of light cycle and a little at a time. The gonostomatids appear to be planktivores that consume small-sized prey; relative size of most preys was about one-tenth of fish length. These feeding patterns could be an adaptive characteristic of fish living in great deep water where the food items are scarcely present. In general there are no considerable inter-and intraspecific differences, not to mention regional differences, in the feeding of the gonostomatids at both stations except the large specimen of Gonostoma elongatum fed fish. Thus several coexisting species of the gonostomatid fish utilize the same resources, showing competitive relationships.

• Journal of Food Hygiene and Safety
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• v.19 no.2
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• pp.74-83
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• 2004

Raw-fish food contains a lot of moisture and is a high-protein food. It is a first-stage processed food taking a lot of manual work. Therefore, it is classified as a PHF food, very liable to cause a bacterial food-poisoning. But its manufacturers are usually small-sized and a systematic sanitation management is difficult to expect. But the manufacturer participating in this study produces chilled fresh raw-fish food. Fish are sliced into two fillets, which are packaged under vacuum, kept and distributed in refrigerators, and sold within a day. It is a newly-developed kind of raw-fish food, and a more improved kind of raw-fish food making possible a systematic sanitation management. The HACCP (Hazard Analysis and Critical Control Point) is a systematic and continuous process-control method which is very efficient for controling food sanitation and reducing the expenses. A new HACCP model has been developed to be applied to a large-sized chilled fresh raw-fish food manufacturer. To ascertain its efficiency, the baterial examination was done to its workplace and products. The significance test was done on its data by "SPSS 12.0 for Window" and "Mann-Whitney U Test". The numbers of bacteria on its final products were significantly different in flatfish and porgy. The number of bacteria tended to decrease in each time-differential sampling (P＜.00l). The final food products showed no food-poisoning bacteria in all the time-differential tests and in all the samplings, which proves that the CCP of the HACCP system is under control. After the SSOP program was applied, no pathogenic bacteria were found in the work-place, and the kinds and numbers of bacteria decreased. The numbers of general bacteria and colon bacilli also showed a significant difference from those before the SSOP program in the filleting board (P＜.05), in the skinning board (P＜.0l), in the neck-removing knife (P＜.05), and in the filleting knife (P＜.01). The working equipments, periodically disinfected, also showed a significant difference in sanitary conditions (in the dehydrator, P＜.05). The number of bacteria found on the food-touching surface was within the standard (below 500/l00 cm$^2$) After the SSOP program was applied, the general bacteria and colon bacilli were not found. The quality of water used in the food processing was also within the standard. The numbers of bacteria falling from the air in the work-place were negligible in all the samplings (＜30CFU/l000ι). The staphylococci and fungi were not found.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.137-140
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• 2002

To determine if fish density, biomass, species richness, and species diversity were greater in ecotone than the stream and littoral zones, I sampled fish monthly in the Ledbetter Creek through Ledbetter Creek Embayment in Kentucky Lake, Kentucky, from April to October 1996 by using throw traps. During the first four months (daytime only) fish density did not vary significantly among zones or among months. However, there were significant differences among zones during the last three months and the stream zone had significantly higher mean fish density than both the littoral zone and the ecotone. Fish biomass also differed significantly among zones during the last three months. The stream zone had the highest mean fish biomass among zones, significantly higher than the ecotone, but not different than the littoral zone. There were no statistically significant differences among zones during the first four months, but mean fish biomass in the stream zone was about eight times higher than the ecotone, The stream zone had the highest fish species richness among zones. Differences were significant among zones during the last three months, and the stream zone (0.98 $\pm$ 0.04) had significantly greater mean fish species richness than the ecotone (0.45 $\pm$ 0.01), but not significantly than the littoral zone (0.56 $\pm$ 0.17). Fish species richness differed significantly among months during the first four months, Monthly species diversities ranged from 0.62 to 1.96 in the stream zone, 0 to a.57 in the ecotone, and 0 to 2.60 in the littoral zone. Combined species diversities in the stream, the ecotone , and the littoral zones were 2.72, 3.58, and 3.10, respectively, There were five families of fishes captured frequently enough for their individual numbers to comprise at least 8 % of the total. Family rankings in the stream zone were opposite of the littoral zone. Percidae was the most abundant family and Clupeidae was absent in the stream zone, whereas Percidae was uncommon and Clupeidae was the most abundant family in the littoral zone. Atherinidae was dominant in the ecotone. Five of the most abundant species comprised 65 % of the total number. The guardian darter occurred only in the stream zone, and it was consistently found in riffles. Longear sunfish and central stoneroller also had significant differences of mean fish densities among zones, and they were found mostly in the stream zone. Threadfin shad and bullhead minnow were almost exclusively caught in the littoral zone. I finally concluded that the ecotone between the stream and the littoral zone in this small-scale freshwater aquatic ecosystem was not as productive as the ones in other ecosystems.

• Journal of Nutrition and Health
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• v.29 no.5
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• pp.472-479
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• 1996

To investigate the effect of dietary lipids and stress on brain catecholamine and serotonin concentration, sixty three weanling male Sprague-Dawley rats(mean body weight$\pm$SD : 171$\pm$3g) were fed a diet containing fish oil, soybean oil or beef tallow and than, each was exposed to three different types of stress, isolated, grouped or cold, respectively. Cold stress seemed to be most severe and living together in a large cage with some playing equipments is more stressful than living alone in a classical small cage evidenced by plasma corticosterone level. Average food intake and body weight gain were not significantly different among exprimental groups. In adrenal catecholamines, norepinephrine was significantly affected by diet and stress and dopamine was by stress. Norepinephrine concentration of the fish oil group was lowest among diet groups. Adrenal epinephrine, however, was not. It was also shown than the cold stress significantly increased the brain norepinephrine concentration. The cold stress significantly induced higher content of brain serotonin than the grouped stress. However, the concentratin of 5-hydroxyindoleacetic acid(5-HIAA), the metabolite of serotonin, was not significantly different among groups. Therefore, this results suggest that stress affects sympathetic neuronal activity, and fish oil might lighten the burden of stress.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.37-42
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• 1981

Ichthyophonus disease broke out among rainbow trout (Salmon gairdneri) fry in November 1979, and after that a fish group containing diseased fish was kept for one year. The authors examined histopathologically the diseased fish 3 times, at 6 momths intervals. Diseased fish showed markedly stunted growth and darkish coloration, and anatomically the liver with small white nodules, the heart with red nodules, the spleen with granular nodules and the markedly tumefied kidney. Ichthyophonus invaded various tissues in the host and took the shape of multinucleate spherical or hyphal body. The multinucleate-spherical bodies contained many nuclei with a large nucleolus and granular cytoplasm. Histopathologically systemic dissemination and systemic proliferation by Ichthyophonus sp. wire indentified. In addition to a single multinucleate-spherical body appeared in the various tissue, large granulomas containing two to several generations of Ichthyophonus sp. were formed especially in the liver, kidey and spleen. The inflammatory response against Ichthyophonus was characterized by mononuclear-celluar proliferation with giant cell formation and fibrobasts proliferation.

• Journal of fish pathology
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• v.7 no.1
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• pp.47-51
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• 1994

The number of maximum 63 Caligus curtus was counted culturing P. olivaceus body surface of 20cm mean body length. respectively. Parasite sites were consist of 63.4% head, 26.9% caudal peduncle, 8.3% operculum and 1.4% the other sites. Also, the sites were secreted in larage quantity of mucus with a very small bleeding. This Caligus parasite was died 15 min to 5ppm and 5min to 10ppm masoten but 28.57% was exterminated to fresh water during the four hours. On the other hand, these Caligus parasites were not exterminated during the 30 min to 200ppm formalin.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.1-8
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• 1989

Demersal fish community in Cheonsu Bay was analyzed using fish samples collected by a small otter trawl from March to November, 1986. Of the 32 species identified, Nibea argentatus, Chaturichthys stigmatias Crptocentrus filifer, Cynoglossus joyneri and Jonius belengeri pre-dominated in abundance. Based upon principal component analysis of species composition data, the fishes were grouped into resident, migrant and temporal species. Resident fish wintered in the deeper part of the bay, showing a peak in biomass during cold months. In spring, warm weather seasonals, adult N. argentatus and J. belengeri, migrated o the bay for spawing. However, the biomass of the migrant was not more than that of the wintered adult residents. From July to September, juveniles of many species were collected, but the number of individuals was smaller than that of the littoral or pelagic zones. This suggests that the deeper area of the bay did not serve as a main nursery ground of the juveniles with the exception of two migrant scianid fishes. As a result, the benthic fish of the bay were more abundant in cold months than in summer.

• 보존과학연구
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• s.19
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• pp.23-34
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• 1998

Bokam-ri site was excavated from July 1996 to September 1998 and archaeologically assumed to be grouped with tombs of Mahan period. Among these groups, Tomb No. 3 had built up with stone chamber and found one pair of gilted footware near the jar coffin. This footware was severely corroded and cracked so transfered it gently with soil. Radiography film of this footware showed spike decorations on the bottom and fish-shapped ornament. Gilted footware was consolidated with soil using Paraloid B72 10%~15%solution and cleaned using small tools and microscope. SV427 and HV427 as epoxy resin and Araldite(rapid type) used for joining and restoring. The fore part of gilted footware was connected with nails and folded “L” shape to introduce the bottom material. Tortoise-shell design and flower ornaments appeared on the surface and fish-shaped ornaments, spikes and spangles on the bottom. It was found that 7 spikes and 5 fish-shaped ornaments remained well. Especially, Fish-shaped ornaments were firstly found in the gilted footware and appraised archaeologically important materials.

• Journal of Marine Bioscience and Biotechnology
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• v.3 no.1
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• pp.18-23
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• 2008

Fisheries constitute an important sector in national economic development, and estimate to contribute about 3% of the total GDP and 5% of the GDP in agriculture. Fish production from aquaculture has been estimated at 950 tonnes for 2004. In 2003, Ghana produced only 51.7% of its requirements from its domestic sources and in 2004, achieved 68.1% of its fish requirement through domestic production and imports. It has been estimated that the production from ponds and culture-based fisheries is worth about US$ 1.5 million a year. The aquaculture sub sector comprises largely small-scale subsistence farmers who practice extensive aquaculture in earthen ponds in contrast to the intensive practices of commercial farmers. There is one cage facility which produces 200 tonnes or 21.1% of the total output. There are several laws to regulate and govern the sector and the government has set up institutions that are responsible for developing fisheries and aquaculture policy and directing and establishing research priorities. The Directorate of Fisheries (DoF) is the lead government agency for aquaculture development and the Water Research Institute of the Council for Scientific and Industrial Research (CSIR) is mandated to carry out aquaculture research. To promote fish farming, imports of farm fish are not allowed.

• Molecules and Cells
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• v.23 no.3
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• pp.331-339
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• 2007

It has been suggested that the structure and function of nuclear receptors are evolutionally conserved. Here, we compare the molecular functions of the nile tilapia (Oreochromis niloticus) small heterodimer partner (nSHP/NR0B2) and the Dosage-sensitive sex reversal AHC critical region on X chromosome gene 1 (nDAX-1/NR0B1) with those of human SHP and DAX-1 (hSHP and hDAX-1, respectively). We found that, upon transient cotransfection of human cells, nDAX-1 repressed the activity of tilapia SF-1 (nSF-1) but not that of human SF-1, although the physical interaction with human SF-1 was retained. Similarly, nSHP repressed the activity of nSF-1, whereas hSHP did not, pointing to divergent evolution of SHP/SF-1 in fish and human. We thus propose that the repressive functions of SHP and DAX-1 have been conserved in fish and mammals although with different transcriptional targets and mechanisms. These differences provide new insights into the physiological diversification of atypical orphan nuclear receptors during vertebrate evolution.