• 한국수산과학회지
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• 제34권6호
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• pp.697-704
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• 2001

단순 구성된 동물 먹이생물 급이 계열 (로티퍼-알테미아)을 이용하는 해산어의 종묘 생산 과정에서는 알테미아 수급 불균형 및 가격 파동 발생으로 알테미아를 대체할 수 있는 새로운 먹이생물의 개발을 요구하고 있다. 이 연구에서는 알테미아 대체 먹이생물로서 담수산 물벼룩 M. macrocopa과 기수산 물벼룩 D. celebensis의 이용 가능성을 검토하기 위한 일환으로 해수에서의 반응 결과 (생존과 증식)를 알아보았다. 담수산 물벼룩 M. macrocopa과 기수산 물벼룩 D. celebensis을 이용하여 배양 환경으로서 다양한 염분 조건으로의 점프 이동 후 두 종 물벼룩의 생존과 증식 반응을 관찰하기 위하여 16일간의 실험 기간 중 매일의 증식 상태와 단시간 생존율을 관찰하였다. 이 연구 결과, 기수산 물벼룩 D. celebensis는 0 ppt의 염분 배양 환경을 제외한 전 실험구에서 비교적 양호한 생존과 증식 반응이 관찰된 반면, 담수산 물벼룩 M. macrocopa은 염분 농도 4 ppt 이상의 점프 이동 환경하에서는 섭이 행동과 유영 행동이 급속히 둔화되면서 증식은 물론 생존조차도 불가능한 것을 알 수 있었다. 특히, 담수산 물벼룩 M. macrocopa의 단시간 생존율을 관찰한 결과에서는 3 ppt 이상의 염분 농도로 점프 이동한 경우에는 점프이동 후 5분 이내에 일부 사망 개체가 발생하는 것이 관찰되었다. 이 연구의 결과, 기수산 물벼룩 D. celebensis은 담수산 물벼룩 M. macrocopa과는 달리 현재 많은 연구가 수행되고 있는 코페포 다와 함께 해산어의 종묘 생산 과정에서 알테미아의 대체 먹이생물로 연구를 진행할 가치가 있는 것으로 판단되었다.

• 한국양식학회지
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• 제12권4호
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• pp.303-307
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• 1999

Copepod is useful live food organism in the larval rearing. However of fin fish, culcures of copepod species (Specially calanoida and cyclopoida) were very difficult under artificial management conditions. In this study, we report successful culture of a free swimming cyclopodia copepod species (Apocyclops sp.) by easily baker's yeast as food. The maximum culture density of Apocyclops sp. was observed 11,200±2,660 ind/ℓ during the 30 days culture periods in the 1.5ℓ culture tanks. The nauplii were growth up maximum density 6,400±432 ind/ℓ on day 16th. The number of egg carring female was observed maximum density (666.7 ind./ℓ) of two times after 6days and 28 days of initial culture.

• 한국수산과학회지
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• 제34권6호
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• pp.605-610
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• 2001

이 연구에서는 해산어의 종묘 생산 과정에서 rotifer의 다음 단계 먹이생물로 이용되고 있는 Artemia의 대체 먹이생물로서 Diaphanosoma celebensis의 배양 환경 중 염분 농도가 미치는 영향을 검토하였다. 염분 농도 0 ppt에서 45ppt 사이에서 5 ppt 간격으로 염분 조정된 10단계의 조건하에서 D. celebensis의 증식 밀도, 안정배양 가능정도 (RPGI: Relative Population Growth Index) 그리고 먹이섭 이력 (RCN; Remaining Cell Numbers)을 비교 검토하였다. 그 결과, 염분 농도 0ppt에서 45ppt까지 10단계의 염분 배양 환경하에서 가장 높은 증식 밀도, 안정 배양도 (RPGI) 그리고 양호한 섭이력 (RCN)이 관찰된 실험구는 염분 농도 20ppt였으며, $15\~35ppt$의 염분 배양 환경하에서도 비교적 안정적인 배양 결과가 관찰되었고 20ppt를 중심으로 저염분 또는 고염분 배양 조건으로 갈수록 증식, RPGI 그리고 RCN은 저하되는 경향이 뚜렷하였다. 그리고 염분 농도 0ppt에서는 실험 개시 직후 전 개체가 사망하였다. 이 연구 결과 D. celebensis는 해산어의 종묘 생산 과정에서 Artemia의 대체 먹이생물로 광범위한 염분 농도 범위하에서 비교적 손쉽게 배양 가능할 것으로 판단되었다.

• 수산해양교육연구
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• 제26권1호
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• pp.1-9
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• 2014

One of freshwater rotifer (Brachionus calyciflorus) is very useful as a live food organism for early larval rearing of freshwater aquaculture industry. However, the knowledge about freshwater rotifer culture is scarce. On the other hand, marine rotifer culture as live food organisms is done, almost perfectly. In this study, I show to be benefit experimental results for successful freshwater larval rearing through the observation with microcosm structure in freshwater rotifer culture tanks.

• 한국산학기술학회논문지
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• 제19권11호
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• pp.682-687
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• 2018

본 연구는 넙치 (Paralichthys olivaceus) 자어에 대한 요각류 Paracyclopina nana의 먹이가치를 평가하기 위해 두섭식 단계 (rotifer 섭식 단계와 Artemia 섭식 단계)로 나누어 각각 12일 및 16일 동안 수행되었다. Rotifer 섭식 단계 실험에서, 넙치 자어의 생존과 성장은 부화 12일째 rotifer만 공급했을 때 보다 P. nana (nauplii) 단독으로 공급했을 때 더 높게 나타났다. Arteima 섭식단계 실험에서, 부화 30일째 넙치자어의 성장은 P. nana (C4-adult) 단독 공급실험구와 혼합공급(P. nana+Artemia) 실험구가 다른 실험구에 비해 높게 나타났으나 넙치 자어의 생존은 모든 실험구가 유의적인 차이를 보이지 않았다. P. nana nauplius와 성체(C4-adult)의 n-3 HUFA 함량은 각각 4.0%와 5.4%였다. 결과적으로, 기수산 요각류 P. nana는 해수어 종묘생산을 위한 초기생먹이로 효과적인 것으로 판단된다.

• Fisheries and Aquatic Sciences
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• 제3권3_4호
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• pp.222-227
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• 2000

Fabrea salina living at salt pond is an interesting ciliate in the research of photobiology and live food for aquaculture. This study was carried out to understand the natural habitat of F. salina at salt pond, which would be a basic biological knowledge for the indoor mass culture of this ciliate. In this research, the water quality as temperature, salinity, dissolved oxygen, and chlorophyll-a was examined with the population density of the ciliate at salt pond. The highest population density of F. salina occurred at 109 ppt and $31^{\circ}C$with 2,390 inds./L in August, and the distribution of the ciliate was positively correlated with salinity, temperature, and chlorophyll­a. Even though F. salina is a very euryharine ciliate, it did not occur at the salinity below 47 ppt in this study. Its reason is able to be explained with the occurrence of many predators as small fish and food competitors as zooplankton living at low salinity of salt pont. While F. salina occurred with Anemia at the same habitat using the same food source, the optimum salinity for the ciliate was a little higher than that of Anemia, and the optimum temperature for the former was a little lower than that of the later. This should be a reason for that these two species have different ecological nich at the same habitat using the same food source.

• 한국수산과학회지
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• 제42권1호
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• pp.56-62
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• 2009

Feeding regimens was investigated for the growth and survival rate of juvenile Maroon clownfish (Premnas biaculeatus) in order to establish a seed production technique for this fish. Three types of feeding regimens were used, and growth and survival were highest under the following regimen: rotifer from day 0, Artemia from day 4, copepod from day 9 and artificial food from day 15, respectively (P<0.05). The average body lengths of the larvae were $6.76{\pm}0.55\;mm$, $7.63{\pm}0.50\;mm$ and $7.33{\pm}0.43\;mm$ in the Nannochloropsis oculata, Isochrysis galbana and control treatments conducted with 3 larvae/L, respectively (P<0.05). There were significant differences in larval growth between the treatments and controls conducted with 6 larvae/L and 9 larvae/L, respectively (P<0.05) but there was no significant difference between the N. oculata and I. galbana treatments (P>0.05). There were no significant differences in larval growth between the treatments at densities of 3-9 larvae/L (P>0.05). At highest density level, the larvae reared in I. galbana had the highest survival rate whereas survival was lowest in the control.

• Parasites, Hosts and Diseases
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• 제43권4호
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• pp.141-147
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• 2005

A practical and convenient method of rearing Eucyclops serrulatus in a microculture environment is described. A complete life cycle of E. serrulatus was maintained in a narrow space on a microscope slide glass on which a cover glass of $22{\times}40mm$ in size was mounted at a height of 0.8mm. The culture medium was constituted by bottled mineral water boiled with grains of Glycine max (soybean). Chilomonas paramecium, a free-living protozoan organism, was provided as live food. Growth of nauplii hatched from eggs to the first stage of copepodite took an average of 7.7 days, and the growth of copepodite 1 to the egg-bearing adult female took an average of 20.1 days in the microculture cell with an average life time of 44.7 days. Continuous passage of cope pods was successfully maintained as long as sufficient medium and food were provided. The microculture method enables an in situ microscopic observation on the growth and developmental process of helminth larvae experimentally infected to copepods as well as of copepod itself. Furthermore, it does not require anesthetization and, therefore, minimize the amount of stress exposed to cope pods during the handling process.

• 한국조경학회지
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• 제18권2호
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• pp.111-125
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• 1990

Korea is a nation with poor natural resources. There is a greats need to save resources that are running out in fast face. The purpose of this thesis is to bind the means to save rosources in housing site, especially in highrise apartment. The reason why the high-rise apartments are chosen as a case is 7hat the high-rise is becoming the major form of dwelling in most urban areas. As a tool of saving the ecological way is chosen because ecological energy is free, clean and unlimited. The resources to be saved are divided into two categories, namely energy and non - energy resources as water, land and food. The contents of the thesis are comprised of 4 chapters. The early chaspters are devoted to the understanding of the ecosystem and problems of current energy consumption in the apartment. It is fellowed by the introduction of the hypothesis that can possibly save reouruces. The hypothesis are then transformed into the actual theories through verification, to be established as the new techniques of the site planning. The ecosystem is the functional relationship between the living organisms and their physical surroundings. The living organisms are the plants that produce, animals that consume and bacterias that decompose. They live in the environment which consists of the three worlds of atmosphere, hydrosphere and lithosphere. The whole system is activated by the solar energy that turns the inorganic mallet- into the living organism and back to the inorganic. It is the recycling principle of the ecosystem. The elements of ecosystem that fan be unilimited as the tools of resources -saving are the sun, wind, water, soil, plant and waste. They are unlimited sources of energy. free of pollution and cheap in price. Each of these ecological elements Provide the opportunities that can save the heating fuel, air conditioning energy, water resource, land and food. The ecological approch should be pursued actively in this age of short resources and growing pollution. In the scale of total energy consumption the housing takes the second position next to the industrial use. It is followed by the transportation which shows for less consumption than former two.

• Journal of Microbiology
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• 제43권2호
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• pp.133-143
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• 2005

Shigellosis is a global human health problem. Four species of Shigella i.e. S. dysenteriae, S. flexneri, S. boydii and S. sonnei are able to cause the disease. These species are subdivided into serotypes on the basis of O-specific polysaccharide of the LPS. Shigella dysenteriae type 1 produces severe disease and may be associated with life-threatening complications. The symptoms of shigellosis include diarrhoea and/or dysentery with frequent mucoid bloody stools, abdominal cramps and tenesmus. Shigella spp. cause dysentery by invading the colonic mucosa. Shigella bacteria multiply within colonic epithelial cells, cause cell death and spread laterally to infect and kill adjacent epithelial cells, causing mucosal ulceration, inflammation and bleeding. Transmission usually occurs via contaminated food and water or through person-to-person contact. Laboratory diagnosis is made by culturing the stool samples using selective/differential agar media. Shigella spp. are highly fragile organism and considerable care must be exercised in collecting faecal specimens, transporting them to the laboratories and in using appropriate media for isolation. Antimicrobial agents are the mainstay of therapy of all cases of shigellosis. Due to the global emergence of drug resistance, the choice of antimicrobial agents for treating shigellosis is limited. Although single dose of norfloxacin and ciprofloxacin has been shown to be effective, they are currently less effective against S. dysenteriae type 1 infection. Newer quinolones, cephalosporin derivatives, and azithromycin are the drug of choice. However, fluoroquinolone-resistant S. dysenteriae type 1 infection have been reported. Currently, no vaccines against Shigella infection exist. Both live and subunit parenteral vaccine candidates are under development. Because immunity to Shigella is serotype-specific, the priority is to develop vaccine against S. dysenteriae type 1 and S. flexneri type 2a. Shigella species are important pathogens responsible for diarrhoeal diseases and dysentery occurring all over the world. The morbidity and mortality due to shigellosis are especially high among children in developing countries. A recent review of literature (KotIoff et al.,1999) concluded that, of the estimated 165 million cases of Shigella diarrhoea that occur annually, $99\%$ occur in developing countries, and in developing countries $69\%$ of episodes occur in children under five years of age. Moreover, of the ca.1.1 million deaths attributed to Shigella infections in developing countries, $60\%$ of deaths occur in the under-five age group. Travellers from developed to developing regions and soldiers serving under field conditions are also at an increased risk to develop shigellosis.