• 한국수산과학회지
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• 제49권3호
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• pp.337-342
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• 2016

Sea cucumbers have been an important part of human diets throughout history; demand is increasing every year, making the species a target for coastal resource development. New harvesting technologies have been developed in response to demand, including nursery production and insemination aquaculture, but such methods produce relatively few individuals and productivity per unit area is very small. For example, captures are prohibited during July and August due to the breeding season, and sea cucumbers aestivate during the hot season and hibernate during the cold season, all factors that limit natural-environment production in Korea. Problems with slow growth of sea cucumbers have been encountered in previous rearing experiments. To assess the importance of feeding ecology on sea cucumber growth, we conducted pond-bottom and lantern-net culture experiments. Results showed that sea cucumbers in bottom cultures grew from 3.06 to 102.59 g, but those in lantern cultures only grew from 25.60 to 28.03 g.

• Animal cells and systems
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• 제1권4호
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• pp.571-576
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• 1997

The playas of the Southern High Plains (SHP) of Texas, USA are an important habitat for over one million wintering waterfowl. However, the recent trend toward the modification of playas for agricultural use is threatening winter habitat of waterfowl in this region. Diurnal activity budgets of wintering mallards (Anas platyrhynchos) were conducted from 1 October to 31 March, 1983-1984, and 1984-1985) at three habitat types; steep-sided pits, terraced pits, and open lakes. All seven activity patterns (feeding, locomotion, resting, comfort, courtship, alert, and agonistic) were different (P<0.05) among the three habitat types for wintering mallards on the SHP of Texas. Terraced pits supported more feeding activity (27.8%) (P<0.001) than steep-sided pits (11.2%) or open lakes (2.6%) due to their abundance of natural seeds and aquatic invertebrates. Hens (17.5%) fed more than drakes (11.7%) (P<0.05). Locomotion (32.2%) and alert (2.8%) behavior across the three habitat types showed the highest level during the early morning (6:00-9:00 AM). Paired mallards rested more (37.9%) than unpaired mallards (25.8%) (P<0.05). Agonistic activity was highest (2.4%) in terraced pits throughout the season.

• 한국환경농학회지
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• 제28권4호
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• pp.356-364
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• 2009

In 2006 and 2007, there was a big outbreak of the Ussur Brown Katydid, Paratlanticus ussurriensis in the central part of Korea attacking some orchard trees. Until 2000, the katydid had not been regarded as an agricultural pest because they were distributed widely in Korea with low population density and their habitats were confined mainly to hillsides of forested areas. The fact that katydid attacked orchard trees with a higher population density seemed to be related to a change in feeding environment. And the shift of their habitats from oak woodlands to commercial orchards was thought to be related to the nutritional contents of their feed. In an attempt to understand these relationships, we conducted an ecological study of the affected areas. When the katydids changed their habitats in early May of 2008 and 2009, they shifted their host plants from oak trees to peach trees. The habitat shift was closely related to the nitrogen (N) content of the host plant leaves. When katydid moved to the hillside adjacent to orchard farm, N content of oak tree leaves decreased dramatically from 5.3% to 2.2%. At that time N content of peach tree leaves were higher than the 2.2% of oak leaves, showing 3.5~5.0%. This range of N content of peach tree leaves has been consistent until late June. And feed preference analysis carried out in the laboratory showed that katydid prefered peach tree leaves to peach fruit to oak tree leaves.

• Asian-Australasian Journal of Animal Sciences
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• 제21권11호
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• pp.1642-1650
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• 2008

The objective of this study was to assess the effect of clinoptilolite (a natural zeolite) on growth and performance of broilers as well as on the quality of their litter. A total of 5,200 one-day old broiler chickens (Cobb 500) were used in two consecutive rounds lasting 42 days each. The broilers were given free and continuous access to a nutritionally non-limiting diet (in meal form) that was either a basal diet (B) or a 'zeolite diet' (Z; the basal diet supplemented with clinoptilolite at a level of 2%). A $2{\times}2$ factorial design consisted of two feeding treatments (B and Z) and two bedding types, sawdust (S) and sawdust with zeolite (Sz, which was the result of adding $2kg\;zeolite/m^2$), was used. In each round the broilers were randomly assigned to one of four (n = 650), treatment groups: two fed on the basal diet (B) and had bedding of either sawdust (group BS) or sawdust and zeolite (group BSz) and two fed on the Z diet and had as bedding either sawdust (ZS) or sawdust and zeolite (ZSz). Average growth rates were significantly (p<0.05) different between broilers of different groups; broilers that were fed on the 'zeolite diet' (Z) and were placed either in a compartment with sawdust bedding or sawdust bedding and zeolite (ZS and ZSz) as well those that were fed on the basal diet in a compartment with sawdust bedding and zeolite (BSz) grew at a faster rate (p<0.05) compared with those of the control group (BS). The incorporation of NZ in broilers diets and in their bedding material decreased the organic content in litter samples throughout the experimental period. The lowest organic content was recorded in group ZSz where NZ was added in both feed and litter. Mean ammonia concentration (ppm) was significantly higher in group ZS in comparison to groups BSz and ZSz (27.00 vs. 20.55 and 21.71 respectively). The results of this study showed that the incorporation of the clinoptilolite both in feed and into the litter had a positive effect on broiler growth and also on the quality of their litter.

• 한국환경생태학회지
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• 제22권4호
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• pp.420-426
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• 2008

본 연구는 무심천의 상류부터 하류까지 총 9개 지점을 선정하여 수서곤충의 EPT-group을 이용하여 EPT-비율, EPT 풍부도, EPT 종수와 개체수를 지점별로 비교분석하였고 수서곤충의 종 조성에 따른 UPGMA분석으로 조사지점간의 유사도를 비교하였으며 수서곤충의 섭식기능군은 하천차수에 의해 비교분석하였다. 조사결과에 의하면 무심천의 수서곤충은 총 8목 36과 71종으로 조사되었고 EPT 비율과 EPT 풍부도는 지점 3에서 각각 0.72, 3.89로 다른 지점에 비해 다소 높게 나타났으며 이와 반대로 지점 9에서는 0.03, 0.09로 비교적 낮게 나타났다. 또한 EPT 종수 및 개체수는 지점 9에서 가장 낮게 나타났다. UPGMA분석 결과 무심천의 각 지점은 A1(st. 1, 7, 8), A2(st. 2, 3, 4, 5, 6), B(st. 9)로 3개의 그룹으로 나뉘었으며 섭식기능군은 지점별 차이는 나타나지 않았지만 상.중류역에서는 써는무리와 긁어먹는 무리가 다른 지점에 비해 다소 높게 나타난 반면 하류에서는 걸러먹는무리와 줍는무리가 우세한 것으로 확인되었다. 본 연구 의하면 조사지점에 따라 수서곤충의 EPT-richness, EPT-ratio, EPT 수 뿐만 아니라 섭식기능군의 조성에도 영향을 주는 것으로 나타났다.

• 한국환경생태학회지
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• 제24권5호
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• pp.556-565
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• 2010

본 연구는 왕피천의 섭식기능군을 이용해 군집분석을 실시하기 위한 것으로 2007년 10월부터 2008년 5월까지 총 4회에 걸쳐 조사를 수행하고 그 결과를 분석하였다. 조사시기동안 출현한 저서성 대형무척추동물은 총 4문 6강 16목 58과 138종이었으며, EPT index 값은 61.59%로 매우 높게 나타나 왕피천의 하천생태계는 매우 청정하고 건강한 것으로 분석되었다. 왕피천의 하천지점별 섭식기능군을 살펴본 결과 긁어먹는 무리와 주워먹는 무리가 지류에 비해 우점하고 있는 일반적인 하천 중류의 특징을 보이는 그룹과 썰어먹는 무리가 본류에 비해 높은 비율을 차지하고 있는 상류 특성을 보이는 지류의 그룹인 두 개의 그룹으로 나뉘어졌다. 유사도 지수를 근거로 각 지점별 클러스터 분석을 실시해 본 결과, 자연 상태의 비교란 지역(A그룹)과 제방 및 보 등에 의한 인위적 교란지역(B그룹; 지점 8, 11)으로 그룹화 되었다. 또한 비교란 지역은 본류(지점 1, 2, 3, 4, 7) 및 지류(지점 5, 6, 9, 10)의 특성을 갖는 두개의 그룹으로 분류됨을 확인 할 수 있었다.

• 한국환경생태학회지
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• 제20권2호
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• pp.259-266
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• 2006

2004년 5월 29일부터 2004년 11월 6일까지 4회에 걸쳐 원주천의 섭식기능군을 이용해 군집분석을 하였다. 조사기간동안 출현한 수서곤충은 총 8목 37과 62속 92종이었으며, 원주천의 현존량과 동태는 지점 7, 9를 제외하고 양호하였다. 원주천의 섭식기능군(FFG)을 알아본 결과 본류는지점 1에서 9로 갈수록 써는무리(shredders)와 긁어먹는무리(scrapers)가 점차적으로 점유율이 낮아지고 주워먹는무리(collectors-gathering)와 걸러먹는무리(collectors-flitering)가 현저하게 증가하였다. 지점 2는 다른 지류지점에 비해 긁어먹는무리와 써는무리가 다소 높은 비율을 나타내어 산간계류의 특성을 가지고 있었다. 원주천의 각 지점별 유사도분석(UPGMA)을 한 결과 최상류수역을 보이는 지점 1, 2와 중류역의 특성을 보이는 지점 3, 4, 5, 6, 7, 8 그리고 최하류역으로 보이는 지점 9 등, 3개의 그룹으로 나뉘었다.

• 한국환경생태학회지
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• 제32권3호
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• pp.256-260
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• 2018

카니발리즘은 동물계에 널리 알려져 있다. 그러나 조류의 경우 둥지 조사가 아닌 야생에서 관찰되는 경우는 드물다. 이러한 행동은 불규칙적으로 발생할 뿐만 아니라 지속적 관찰이 거의 불가능하기 때문이다. 독수리의 카니발리즘은 2017년 1월 17일 월동지인 해남군 금호호 농경지 주변($34^{\circ}35^{\prime}58.25^{{\prime}{\prime}}N$, $126^{\circ}26^{\prime}57.64^{{\prime}{\prime}}E$) 한 무리의 독수리에서 관찰되었다. 관찰은 현장으로부터 20m 또는 60m 정도 떨어진 곳의 승용차 내에서 쌍안경을 통하여 이루어 졌고, 사진 촬영을 위해 망원렌즈가 장착된 카메라도 함께 사용되었다. 현장에서 취식을 하던 마지막 독수리가 떠난 후 먹이의 잔존물을 확인하였다. 독수리가 취식했던 장소에는 독수리의 몸깃, 두개골, 흉골, 양쪽 다리 등 독수리의 잔존물들이 발견되었다. 그리고 그 외에는 그들의 먹이가 되는 다른 동물의 어떠한 흔적도 발견되지 않았다. 본 연구는 독수리의 카니발리즘에 관한 최초 보고로 카니발리즘에 대한 세부적인 설명 및 그 행동에 영향을 미친 환경적 요인에 대하여 알아보고자 하였다.

• 한국가정과학회지
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• 제8권1호
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• pp.49-58
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• 2005

This study was designed to observe the effects of the feeding Callophyllis japonica extracts on the improvement of the blood glucose, lipid in the serum of dietary hypercholesterolemic rats(S.D. strain, ?) fed the experimental diets for 4 weeks. Concentrations of total cholesterol and LDL-cholesterol in serum were significantly lower in the Callophylis japonica extracts group than in the choloesterol supplemented diet group. Concentrations of HDL-cholesterol in serum were higher in the Callophyllis japonica extracts group than in the cholesterol supplemented diet group. Concentrations of free cholesterol, triglyceride, phospholipid and blood glucose in serum were significantly lower in the Callophyllis japonica extracts group than in the cholesterol supplemented diet group. The activities of aspatate aminotransferae(AST), alanine aminotransferase(ALT), lactate dehydrogenase(LDH) and alkaline phosphatase(ALP) in serum were lower in the CAllophyllis japonica extracts supplemented group than in the cholesterol diet group. From the above research, the physiological activity substances in Callophylis japonica extracts were effective on the improvement of the blood glucose, lipid compositions in serum of dietary hypercholesterolemic rats.

• Molecular & Cellular Toxicology
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• 제4권2호
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• pp.138-143
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• 2008

We investigated if Chlorella vulgaris (CV) has protective effects on cadmium (Cd) induced liver damage in male Sprague-Dawley (SD) rats. Forty rats, aged 5 weeks old and weighed 90-110g, were divided into a control (with Cd free water), 50 ppm of $CdCl_2$ in drinking water treated groups (Chlorella 0% diet group (Cd/CV0%), Chlorella 5% diet group (Cd/CV5%) or Chlorella 10% diet group (Cd/CV10%). All the rats had freely access to water and diet for 8 weeks. The results show that body weight gain and relative liver weight had significantly lower in Cd/CV0%-treated group than in Cd/CV-treated groups. Hepatic Cd contents showed significantly less by feeding CV (P<0.05). Cd/CV0%-treated rats had significantly (P<0.05) higher hepatic T-MTs, and Cd-MTs concentrations, compared to Cd/CV5% or Cd/CV10% treated rats. The MT I/II mRNA was expressed in the liver of all experimental rats. Its expression was more increased in Cd/CV5%- or Cd/CV10%-treated rats, compared to control and Cd-treated rats. Thus, this study suggested that CV would have a protective effect on Cd-treated liver injury by the reduction of Cd concentrations and stimulation of Cd-MT binds in the liver. However, more studies are needed to identify the proper mechanism of CV and liver toxicity.