• Korean Journal of Ichthyology
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• v.20 no.1
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• pp.36-44
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• 2008

Feeding habits of Micropterus salmoides were investigated from the stomach contents of specimens ranging from 13 to 511 mm in standard length (n = 419), which are collected in the Lake Okjeong, Korea, 2006 to 2007. M. salmoides is a very strong carnivorous fish eating living organisms such as lots of fishes, small amount of aquatic insects and shrimps. As they grow, the feeding habits changed : they fed mainly on Branchioda in 10 to 20 mm in SL., aquatic insects and small fishes in 30 to 50 mm in SL., fishes including Zacco platypus, Hemiculter eigenmanni and Rhinogobius brunneus over 50 mm. However, among the prey organisms, M. salmoides most preferred living fishes. Analysing ichthyofauna of the Lake Okjeong from 1981 to the present investigation, after and before introduction of M. salmoides, it was showed that there was a certain reduction in fish diversity. Consequently, it is likely to let the strongly fish-eating habit to reduce a diversity of native fishes in the lake.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.456-463
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• 2004

A faunal study on the marine decapods of Gogunsan Islands located in the western part of South Korea was performed during the period from August 3 to August 5 in 2003. As a result of the present study, a total 42 species in 17 families (Macrura: four species in two families, Anomura: nine species in four families, Brachyura: 29 species in 11 families) were identified. Of these, two species of shrimp, Athanas sp. and Alpheus sp., are new to Korea. Including these two species, total 20 species in 10 families are newly known to Gogunsan Islands. Fifty two species in 19 families were previously known to occur in this area. Therefore, a total 72 species in 24 families of decapods are now known to occur in Gogunsan Islands. Of the species collected in the present study, Palaemon (Palaemon) serrifer (Stimpson, 1860) in shrimps, Macrophthalmus japonicus De Haan, 1835 living at mud area and Scopimera globosa De Haan, 1835 at sand beach in crabs, and Hapalogaster dentata (De Haan, 1849) in hermits crab were most dominant.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.1
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• pp.20-28
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• 2005

Species composition and seasonal variation of decapod crustacean assemblage in Hampyeong Bay, Korea were examined. Sampling was monthly made by a shrimp trawl between March 2003 to February 2004. A total of 39 species of 20 families were collected. Of these, Latreutes planirostris, Palaemon gravieri, Parapenaeopsis tenella, Exopalaemon carinicauda, Charybdis japonica, Trachysalambria curvirostris and Palaemon macrodactylus were dominant species comprising $84.3\%$ of the total number of individuals. Charybdis japonica, P. gravieri, Oratosquilla oratoria, E. carinicauda, T curvirostris, Metapenaeus joyneri and P. tenella represented $90.6\%$ of the total biomass. While total abundance (number of individuals) was high in spring, total biomass and species richness (number of species) and diversity were high in summer. Cluster analysis, based on monthly abundance data of the 14 most common species, showed that the species were separated into three different groups. Group A composed of Leptochela gracilis, Alpheus japonicus, Crangon uritai, P. macrodactylus, E. carinicauda, P. gravieri, O. oratoria, C. japonica, which were year round residents, group B M. joyneri, T. curvirostris and P. tenella, which were abundant in summer, and group C Crangon hakodatei, Latreutes anoplonyx and L. planirostris, which were abundant in winter. Principal component analysis revealed that seasonal variation in the decapod crustacean assemblage was attributed to the abundance of temporal species such as penaeid shrimps, which were abundant in summer, due to seasonal variation of water temperature and reproductive pattern.

• ALGAE
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• v.33 no.3
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• pp.279-290
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• 2018

Microalgae have been utilized in diverse industries including aquaculture. Among the microalgae, dinoflagellates are known to have various bioactive compounds, and thus the interest in their application to industry has increased. In order to test their potential as food materials for aquaculture animals, the crude protein contents and compositions of amino acids of six dinoflagellates Heterocapsa rotundata (family Heterocapsaceae), Ansanella granifera (Suessiaceae), Alexandrium andersonii (Ostreopsidaceae), Takayama tasmanica (Brachidiniaceae), Takayama helix, and Gymnodinium smaydae (Gymnodiniaceae) belonging to diverse families were analyzed. The percentage of the amount of the crude protein relative to dry weight of T. tasmanica was the highest (65%) and that of A. andersonii was the lowest (26%). However, the highest percentage of total detected amino acids in crude protein was found in A. andersonii (98.2%). In all six dinoflagellates, glutamic acid was the most dominant amino acid in crude protein. However, the second main amino acid was aspartic acid for H. rotundata, A. granifera, T. helix, and G. smaydae, but were arginine and leucine for A. andersonii and T. tasmanica, respectively. Furthermore, T. tasmanica and T. helix did not have taurine and gamma-aminobutyric acid, whereas the other dinoflagellates possessed them. The percentages of essential amino acid contents of the dinoflagellates met the requirement levels for juvenile shrimps. In addition, the dinoflagellates were not toxic to the brine shrimp Artemia salina. Compared with the other microalgae reported so far, H. rotundata and A. andersonii can be used for arginine-rich diets, T. tasmanica for valine and leucine-rich diets, A. granifera for histidine-rich diets, T. helix for threonine-rich diets, and G. smaydae for lysine-rich diets. Therefore, based on their biochemical composition and toxicity to Artemia, the dinoflagellates could be used as essential amino acid sources for cultivating animals in the aquaculture industry.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.430-436
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• 2019

The diet of Glyptocephalus stelleri was studied using 475 specimens collected in the coastal waters of the East Sea of Korea. The specimens ranged from 6.8 to 43.4 cm in total length (TL). G. stelleri was a crustacean feeder that consumed mainly euphausiids [percent index of relative importance (%IRI)=63.7%]. Polychaetes were the second largest prey component. The diet also included small quantities of bivalves, copepods, amphipods and shrimps. Individuals smaller than 15 cm TL fed mainly on euphausiids. The proportion of euphausiids decreased as body size increased, whereas the consumption of polychaetes increased gradually.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.808-813
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• 2021

The diet composition of Spanish mackerel Scomberomorus niphonius, was investigated using 853 specimens collected using two-boat trawl, stow net, gill net and set net from January to December 2019 from the South Sea of Korea. The size of the specimens ranged from 25.2 to 114.8 cm in fork length. S. niphonius fed mostly on fishes. Its diets also included small quantities of shrimps, cephalopods, crabs, stomatopods, etc. Among them, Engraulis japonicus was the dominant species. The dietary composition of S. niphonius exhibited significant differences based on their size. The proportion of Trichiurus japonicus increased as body size of S. niphonius increased, whereas the proportion of E. japonicus decreased gradually. As the body size of S. niphonius increased, the mean weight of prey per the stomach (mW/ST) tended to increase significantly (one-way ANOVA, P<0.05).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.761-768
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• 2021

This study was carried out to identify an effective method to acclimate low-salinity (4 psu) bred Litopenaeus vannamei (mean body weight 16±3.3 g) to sea water. The fast acclimation group (FA) was directly exposed to filtered sea water (32 psu) while the slow acclimation group (SA) was exposed to a slow increase in salinity. Shrimps were sampled at 0, 1, 3, 6, 12, 24 and 48 h for plasma analyses. The plasma components between experimental groups did not show significant differences. The hemolymph osmolality (HO) in FA increased significantly after 1 h (P<0.05), while in SA it started to increase slowly only at 24 h and reached a similar level to that of FA at 48 h. The levels of Na⁺ and Mg²⁺ ions were significantly different between the two treatments (P<0.05), but there was no significant difference in Ca²⁺ ion levels. We found that the different methods of acclimation of L. vannamei to sea water do not affect the plasma components significantly, but lead to changes in the HO and ion levels, it is considerable to acclimate gradually for at least two days.

• Asian Journal of Business Environment
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• v.11 no.2
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• pp.5-13
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• 2021

Purpose: This paper aims to study the fishing capacity of the shrimp trawlers in the Aru and Arafura Sea. Research design, data and Methodology: The abundant shrimp resources call for its sustainable use to advance economic activity. Time-series data of effort and catch from shrimp trawlers from 1980-2015 were utilized. The technical efficiencies of the vessels and the target capacity of the shrimp fishery were estimated using Peak to Peak Method. Results: Arafura's shrimp fishery presents high technical efficiency, which is suggested by the high scores of its fishing capacity utilization. The issuance of a ministerial decree on the prohibition of the use of trawls has impacted the plummeting of Arafura's shrimp trawler production right after the regulation implemented in 2015, which is far below the total production of the Arafura's shrimp trawler in 1980. Today, the Aru and Arafura Sea has different sets of fishing gears that are dominated by Squid Jigging and gillnet vessels. Conclusions: Arafura shrimp fishery performs high technical efficiency, which is indicated by the high utilization value of its catching capacity ranging from 71% to 100% annually from 1980 to 2015 This has shown that the resource-utilization has shifted from shrimps to other economically important species during the post trawl ban such as squid and pelagic. Any future intention to utilize shrimp resources, interaction of gears harvesting shrimp with current gears should be well considered in the policy making process.

• Nutrition Research and Practice
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• v.16 no.5
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• pp.658-672
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• 2022

BACKGROUND/OBJECTIVES: Although children of ethnic minority groups are experiencing a transition from a predominance of undernutrition to overnutrition, there is little evidence of a dual-malnutrition burden. Therefore, this study examined the double burden of malnutrition among school-aged ethnic minority children living in mountainous areas and its association with their diets. SUBJECTS/METHODS: A cross-sectional study was conducted from September 2019 to March 2020 in 3 mountainous areas of Northern Vietnam among 1,556 ethnic minority school-aged children. The prevalence of under-nutrition (stunting and thinness) and over-nutrition (overweight and obesity) were measured using the WHO 2006 child growth standards (height-for-age and BMI-for-age Z-score). Nutritional practices were evaluated by the frequency of food consumption based on a 4-level scale. RESULTS: The percentage of children with stunting and thinness were 14.0% and 5.4%, respectively, while the figure for overweight/obesity was 9.4%. The factors positively associated with stunting were living in a family with more than 2 children or being Muong/other ethnicities compared to the Tay ethnicity. Children who consumed fish/shrimps/crabs or milk weekly/daily were less likely to be undernourished compared to those who never consumed these foods. By contrast, children who never consumed foods rich in vitamin A precursors and vitamin A and fruit or consumed daily snacks/junk food were more likely to be overweight/obese. CONCLUSIONS: Undernutrition remains a common issue among school-aged children and adolescents of ethnic minority groups, while over-nutrition exists simultaneously. Public health nutrition programs promoting adequate diets and positive lifestyle changes related to nutrition are essential to tackle the double burden of malnutrition among ethnic minority children.

• Journal of the Korean Society of Food Culture
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• v.22 no.4
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• pp.441-448
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• 2007

The purpose of this study was to identify HACCP-based CCP and CP from the microbial quality assessment on the process of side dish (stir-fried dried-shrimp with garlic stems) production in the meal service operation for the elderly. Total plate counts (TPC) of fresh garlic stalks were $7.80{\times}10^{3}$ CFU/g and they were above the standard value of microbial growth potential. The TPC, Coliform and E.coli were not detected in the dried shrimps. The TPCs after rinsing and slicing the garlic stems were $2.5{\times}10^{2}$ CFU/g and $5.5{\times}10^{2}$ CFU/g, respectively. The TPC number of cook’s hand and cutting board were also exceeded the standard limit with values of $2.2{\times}10^{2}$ CFU/g and $10.0{\times}10$ CFU/g, respectively. However, the TPC, Coliform and E.coli were not detected in the other cooking instruments. The identified CCP in inspection step was fresh garlic stems and that of prepreparation step was slicing the stems after blanching. Cook’s hand and cutting board were also verified as CCP and the other steps in cooking process and utensils tested were identified as CP’s. These result’s suggest that it is important to control the microbial contamination of raw materials at purchasing step and the sanitary education program should be developed for the employees for continuous supplement of safe and sound meal service for the elderly.