• Fisheries and Aquatic Sciences
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• 제8권2호
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• pp.83-89
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• 2005

Morphology, histology, and histochemical characteristics of the digestive tract of the guirine goby (Rhinogobius giurinus: Gobiidae), collected from the coast of Jeju Island, Korea, were investigated. The digestive tract of R. giurinus, which is a brackish water species, has a short (relative length of gut=0.42), simple, and narrow gut. The gastric glands are well developed in the stomach, but pyloric caeca are absent. The mucosal folds are regularly branched, and the muscularis extern a is thickest in the esophagus, which also contained the most mucus-secreting goblet cells (P<0.05). In R. giurinus, digestive function occurs in the anterior portion of the digestive tract, where mucus protects the tract from the actions of digestive enzymes and functions to activate digestion.

• 한국패류학회지
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• 제32권3호
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• pp.165-174
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• 2016

바지락의 섭식 특성을 분석하기 위해 서해의 곰소만에서 바지락의 소화관 내용물과 표층 해수의 식물플랑크톤 군집에 대해 정량 및 정성분석을 실시하였다. 바지락의 소화관에는 규조류 (71.5%), 와편모류 (13.1%), 미소플랑크톤 (6.6%) 과 중형동물플랑크톤을 포함한 유기쇄설물 등이 관찰되었다. 소화관내에서 섭식량은 겨울과 봄에 많았고 여름과 가을에 낮게 나타난 반면, 표층 해수의 식물플랑크톤 현존량은 가을에 가장 많았다. 또한 바지락의 크기가 클수록 섭식한 먹이생물의 양은 증가하였다. 소화관에서 관찰된 우점종은 저서성 규조류인 Paralia sulcata 및 Navicula arenaria와 와편모류의 cyst 이었던 반면 표층해수에서 우점종은 부유성 규조류인 Chaetoceros 속, Skeletonema 속, Asterionellopsis 속 등과 cryptomonads 및 P. sulcata이었다. 소화관 내용물 분석을 통해 바지락의 주요 먹이원은 저서성 규조류이며, 식물플랑크톤의 크기와 모양에 따라 선택적으로 섭식함을 확인하였다.

• 한국발생생물학회지:발생과생식
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• 제11권2호
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• pp.121-125
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• 2007

넙치 자치어의 초기 발육단계에 따른 소화관의 형태 발달과정을 관찰한 결과, 부화 직후의 전기 자어는 평균전장 $25.0{\pm}0.14\;mm$(n=20)로 입과 항문이 아직 열려 있지 않았고, 소화관은 배체와 난황 사이에 원시 소화관의 형태로 거의 직선상으로 식도에서 항문이 생길 부분까지 길게 신장되어 있는 형태였다. 부화 후 $7{\sim}8$일째 후기 자어는 평균 전장 $5.05{\pm}0.40\;mm$(n=20)로 소화관이 발달하여 먹이의 섭취활동이 활발하였으며, 소화관은 배쪽으로 팽창하여 장과 연결되어 위가 발달하기 시작하였고, 소화관의 전반부와 후반부가 구별되어 소화기관이 분화하기 시작하였다. 부화 후 $13{\sim}14$일째 후기 자어는 전장이 $6.50{\pm}0.25\;mm$(n=20)였고, 소화관은 앞부분에서부터 1회전되어 회전부분의 면적이 넓어져 있었으며, 소화관이 식도, 전장, 중장, 후장으로 완전히 분화되면서 소화관의 기본적인 구조가 확립되었다. 부화 후 30일째 개체는 전장 $12.40{\pm}0.55\;mm$(n=20)로 위는 비대하여 분문부와 유문부가 뚜렷하게 구별되었고, 소화관은 위, 전장, 중장, 후장 및 직장이 명확하게 구분되어 치어기로 이행하여 성어와 유사한 구조로 발달하였다. 부화 후 40일째 치어는 전장이 $16.15{\pm}0.85\;mm$(n=20)로 소화관 형태는 식도부, 유문부, 장의 전장, 중장, 직장이 크게 팽창되어 상대적으로 후기 자어의 소화관 형태와는 다소 차이가 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.313-316
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• 2000

Three Holstein steers, fitted with ruminal and duodenal cannulas, were used in a replicated $3{\times}3$ Latin square design to determine the digestibility of dietary nitrogen in total digestive tract by three methods, 1) mobile nylon bag (MNB); 2) total fecal collection (TFC); and 3) washed fecal sample after freezing and thawing through a sieve with a pore size of $45{\mu}m$ (WFS). A basal diet of oaten hay-barley was supplemented with one of the following protein sources; soybean meal, fish meal or blood meal. Steers were fed at a level of 2% of body weight. The experimental diets were contained approximately 1.85% nitrogen. There were no differences (p>0.05) among the diets on DM, NDF and nitrogen disappearances, and the diet results were pooled to assess the methods. Total tract disappearances of dry matter and neutral detergent fiber were 61.6, 71.1 and 78.9 and 25.3, 63.2 and 64.6 for MNB, TFC and WFS methods, respectively. The lower digestibility of DM and NDF in the MNB method could be a result of low ruminal incubation time. The TFC method had the lower (p<0.05) determination of nitrogen disappearance in the total digestive tract than the MNB and WFS methods. On the other hand, nitrogen disappearance in the total digestive tract determined by the WFS technique was comparable to that in MNB technique, as there was no significant difference (p>0.05) between the methods. It is shown that the disappearance of dietary nitrogen in the total digestive tract could be estimated in the intact animals by using washed fecal sample prior to freezing and thawing.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.196-201
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• 2005

Diseases in the gastro-intestinal tract are on an increasing trend. In order to diagnose a patient, various signals of the digestive organ, such as temperature, pH, and pressure, can offer the helpful information. Among the above mentioned signals, we choose the pressure variation as a monitoring signal. The variation of a pressure signal of the gastro-intestinal tract can offer the information of a digestive trouble or some clues of the diseases. In this paper, a pressure monitoring system for the digestive organs of a living pig is presented. This is why a pig's gastro-intestinal tract is very similar as human's. This system concept is to transmit the measured biomedical signals from a transmitter in a living pig to a wireless receiver that is positioned out of body. The integrated solution includes the swallow type pressure capsule and the receiving set consisting of a receiver, decoder circuit. The merit of the proposed system is that the monitoring system can supply the precise and a durable characteristic to measure and to transmit a signal in the gastro-intestinal tract. We achieved the pressure tracings in digestive organs and verified the validity of system after several in-vivo tests using the pressure monitoring system. Through various experiments, we found each organ has its own characterized pressure fluctuation.

• Asian-Australasian Journal of Animal Sciences
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• 제16권6호
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• pp.863-866
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• 2003

This study was conducted to examine the effects of dietary cellulose levels on growth, nitrogen utilization, the retention time of diets in the digestive tract, and caecal microflora of 2-month-old Single Comb White Leghorn male chickens fed 3 purified diets that contained 0, 3.5% and 10% cellulose in equal amount of nutrients for 7 days. Body weight gain and nitrogen utilization were significantly higher (p<0.05), while total microflora counts in the caecal contents and retention time of the diet in the digestive tract were significantly lower (p<0.05) in the group fed 3.5% dietary cellulose compared with the group fed 10% dietary cellulose. Body weight gain, nitrogen utilization and retention time of the diet in the digestive tract decreased significantly while the total microflora count in the caecal contents increased significantly in the group fed 10% dietary cellulose compared to the group fed 0% dietary cellulose (p<0.05). Chickens fed 10% dietary cellulose had significantly increased counts of uric acid-degradative bacteria such as Peptococcaceae and Eubacterium, including Peptostreptococcus (p<0.05). The results suggest that cellulose in purified diets is an effective ingredient and the effects on growth, nitrogen utilization, caecal microflora counts and diet retention time in the digestive tract are dependent on the inclusion rate. Positive or negative effects of dietary cellulose are displayed by growth, nitrogen utilization, caecal microflora counts and retention time of the diet in the digestive tract. Positive effects were displayed when the inclusion rate is 3.5% and negative effects were displayed when that is greater than 3.5% of the diet, and the phenomenon is without reference to the age of the chickens.

• 한국발생생물학회지:발생과생식
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• 제7권1호
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• pp.29-34
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• 2003

이 연구는 자주복의 개체발생 단계에 따른 소화관 외부형태의 변화와 소화관의 발달 양상을 조직학적으로 조사하였다. 부화 직전 수정란의 소화관은 난황낭과 배체의 척추 사이에 위치하였고, 형태는 거의 직선상 이었다. 입은 부화 후 2일째, 항문은 부화 후 4일째 열렸다. 부화 후 4일째 소화관은 식도, 전장, 중장 그리고 직장으로 구분이 되었고, 전장과 중장이 괄약근에 의해 구분되었다. 부화 후 5일째 자어는 전장과 중장 사이가 배측으로 굴곡되었고, 식도상피에 점액세포가 분포하였다. 이 시기에 난황은 대부분 흡수되었다 부화 후 6일째 자어의 소화관은 전장이 두부 쪽으로 팽창하면서 U자형으로 분화하였다. 부화 후 10일 째에 팽창한 전장은 더욱 커져서 구형을 형성하였다. 부화 후 15일째 전장의 배측 부위 중간에서 함입되기 시작하여 전장이 두 부분으로 나누어졌다. 부화 후 21일째 전장의 앞부분이 팽창낭으로 분화하였다. 부화 후 24일째에 후장의 앞부분이 배측으로 다시 회전하였다. 부화 후 30일째 팽창낭은 두부 쪽과 항문 쪽으로 길게 신장되어 어미의 소화관 형태로 발달하였다.

• Applied Microscopy
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• 제24권3호
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• pp.34-45
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• 1994

This investigation has been carried out to examine the structure of digestive tract from Korean Leech, Erpobdella lineata, using light and electron microscope. The digestive tract is composed of mouth, pharynx, Oesophagus, six-chambered stomach, three-chambered intestine, rectum and anus. Stomach and intestine have not gastric or intestine ceca and consist of only straight tube. All digestive tracts from pharynx to rectum are covered with simple columnar epithelial cells. While the surfaces of endothelial cell of pharynx and rectum are covered with cuticular layer of about $0.3{\mu}m$ in thickness, stomach and intestine are covered with estimated $0.2-0.3{\mu}m$ and $0.5{\mu}m$ microvilli respectively. Circular folds were found only in first and second chambers of stomach, intestine and rectum, but not in pharynx and the other chambers (third to sixth) of stomach. The granules of $0.3-0.8{\mu}m$ and $0.5-1.0{\mu}m$ in diameter were observed in the cytoplasm of stomach endothelial cell. These granules were demonstrated to contain protein which showed a positive reaction to ninhydrin. It was also found that there are well-developed microvilli in the apical portion of intestine endothelial cell in which endocytosis occurs actively.

• 한국패류학회지
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• 제14권2호
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• pp.131-147
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• 1998

A histochemical and ultrastructural study on the epithelia of some selected digestive tracks such as esophagus, crop, intestine of a land snail N. samarangae was carried out during the period of June 1997 to may 1998. The epithelium of digestive tract are simple columnar epithelium and consisted of five types of columnar cells. Type 1 cell which is majority in number has a brush border with microvilli on the free surface of the cell and contains numerous secretory granules supposed to be neutral mucopolysaccharide. Type 2 cell, elongated conical in shape, is rarely found in the epithelium. This cell also has a brush border with microvilli on its free surface and contains well developed rough surfaced endoplasmic reticulum, Golgi bodies, and secretory granules in various electron densities. This cell seems to produce both of acid and neutral mucopolysaccharides. Type 3 cell, which is morphologically similar to the Type 1 cell, has microvilli and cilia on the free surface and exists in group only in the limited regions of the intestine. Type 4 cell, typical goblet cell containing secretory granules in high electron density. Type 5 cell rarely found in the digestive tract. This cell contain inconspicuous materials.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2006년도 The 6th Intermational Symposium on Developmental Biotechnology
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• pp.91-92
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• 2006