• 수산해양기술연구
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• 제36권4호
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• pp.267-273
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• 2000

민들조개 형망의 갈퀴에 의해 어획될 확률을 조개크기와 갈퀴간격 사이의 관계로부터 구했다. 이때 기존의 방법에서는 각장만을 이용했는데 여기서는 각장 이외에 각고(또는 각폭)에 의한 효과를 추가시켜 어획될 확률을 구하고 로지스틱 어획선택성 곡선에 적합시켰으며, 그식은 다음과 같았다. P=(equation omitted)$.$민들조개의 경우 생물학적 최소형은 각장이 25mm인 것으로 알려져 있으며, 이 최소성숙각장에 대해 50% 어획될 갈퀴간격을 구하면 16.2mm이다. 따라서, 민들조개 형망의 적정 갈퀴간격은 기존에 사용하고 있는 12mm를 16mm로 늘리는 것이 자원보호상 바람직하며, 이것은 예망작업시 모래 속을 끄는 갈퀴의 갯수도 상대적으로 적어지므로 어구저항이 감소되어 연료가 절약되며, 선상에서는 작은 조개를 체를 이용하여 거르는 인력작업도 줄일 것으로 여겨진다.

• 한국패류학회지
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• 제24권1호
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• pp.11-24
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• 2008

GDNA was isolated from the jedo venus clam (Protothaca jedoensis, Lischke) from Boryeong (jedo venus clam from Boryeong JVCB) and Wonsan (jedo venus clam from Wonsan; JVCW) located in the West Sea and the East Sea of Korean Peninsula, respectively and we performed clustering analyses, DNA polymorphisms and the populations genetic variations. In the present study, the seven decamer primer generated the one hundred and eleven major/minor specific bands in JVCB population and ninety four-specific bands in JVCW population. Seven primers generated the unique shared bands to each population of one hundred and seventy-six, on average of 25,1, in JVCB population from Boryeong and three hundred thirty, on average of 47,1, in JVCW population from Wonsan, respectively. The dendrogram obtained by the seven oligonucleotides primers, indicates two genetic clusters. Especially, two Protothaca between the individual WONSAN no. 12 and BORYEONG no. 10 showed the longest genetic distance (0.537) in comparison with other individuals used. Accordingly, RAPD analysis showed that the JVCB was a little more genetically diverse than the JVCW population. This result implies the genetic similarity owing to rearing in the same and/or similar circumstances or inbreeding within the JVCW population. So to speak, JVCB population may have high levels of genomic DNA variability owing to the introduction of the wild individuals from the other sites to sampling sites although it may be the geographically diverse distribution of this species. However, it was confirmed that it did not appear like that really in this study. We feel convinced that RAPD analysis discovered a significant genetic distance between two Protothaca population pairs (P<0.001). The existence of population discrimination and genetic diversity between two Protothaca populations was identified by RAPD analysis.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2004년도 수산관련학회 공동학술대회 발표요지집
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• pp.512-512
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• 2004

Venus clam, Protothaca jedoensis was collected in lune 2003 from Yosu, Korea. The prevalence and infection intensity of Perkinsus was determined by Ray's Fluid thioglycollate medium technique and Choi's 2 M NaOH digestive assay. The prevalence of infection was 80% in Yosu; 54.2% in Taejon and 15.5% in Sachon. Consequently, infection intensity was highest in clams from Yosu (6250${\pm}$8188 Perkinsus cells/g of tissue) whereas lower levels were found in Taejon (5072${\pm}$10862 Perkinsus cells/g of tissue) and in Sachon (2452${\pm}$15300 Perhnsus cells/g of tissue). Histological observation showed that Perkinsus presented in mantle, gills, digestive tubes and gonad of clams. The hemocytic infiltrations and tissue damages were found in heavy Perkinsus-infected clams. Results after immunofluorescence staining with antibody developed from Perkinsus atlanticus suggested that there is closed relationship between Perkinsus found in Venus clam and Manila clam.

• 한국패류학회지
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• 제16권1_2호
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• pp.43-48
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• 2000

기생충 감염에 의한 폐사와 생식세포형성 영향여부를 확인하고자 1999년 6월부터 2000년 5월까지 매월1회씩 전북 부안군 계화도와 고창군 부안면 상포 지선의 간석지에서 양식하고 있는 가무락조개를 채집하여 조사한 결과를 요약하면 다음과 같다. 검출된 기생충은 극구흡충과(棘口吸蟲科, Echinostomatidae)에 속하는Himasthla kusasigi Yamaguti ,1939의 피낭유충(metacercaria)뿐이었다. 양 조사지역에서의 년 평균 기생율은 계화도 93%, 고창 상포 81%이었으며, 월간 가장 기생율이 높았던 시기를 보면 먼저 계화도는 1999년 9월 및 2000년 3, 4월에 100% 기생된 반면에 7월이 80%로 가장 낮은 기생율을 나타냈다. 고창 상포구역은 가장 높았던 달이 2000년 1월 99%, 가장 낮았던 달은 1999년 11월의 47%이었다. 조개내의 Himasthla kusasigi의 기생부위는 다리를 포함한 내장낭, 아가미, 외투막으로써 기생율은 계화도와 고창지역 각각 내장낭 76.7%, 81.3%, 아가미 19.1%. 14.5%, 외투막 5.1%, 4.2%이었다. 조개의 크기가 클수록 기생율이 높았다. Himasthla kusasigi의 피낭유충이 감염된 가무락조개 일지라도 조직학적 조사에서 아무런 이상을 발견하지 못하였다.

• 한국발생생물학회지:발생과생식
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• 제10권4호
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• pp.227-238
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• 2006

한반도의 동쪽에 위치해 있는 삼척(venus clam from Samcheok; VCS)과 원산(venus clam from Wonsan; VCW) 지역에서 채취된 민들조개(Gomphina aequilatera)에서 genomic DNAs(gDNAs)를 분리 추출하였다. 증폭산물은 primer agarose 전기영동법에 의해서 생성되었고, EtBr에 의해서 염색된 이후에 자외선에 의해서 확인되었다. 150 bp에서 2,400 bp에 해당되는 shared loci, polymorphic 및 specific loci를 얻기 위해서 BION-21, BION-23, BION-25, BION-27, BION-29, BION-31 및 BION-33와 같은 7개의 primer를 사용하였다. 본 연구에서 7개의 primer는 VCS 민들조개 집단에서 147개의 polymorphic loci(147/954 loci, 15.41%)와 VCW 집단에서 274개의 polymorphic loci(274/996 loci, 27.51%)를 확인하였다. 이것은 VCS 민들조개 집단에서 보다 VCW 집단에서 더 높은 유전적 변이를 나타내고 있다는 것을 제시하고 있다. 특히 BION-21 primer에 의해서 나타난 700 bp는 민들조개 2개 집단에서 공통적으로 확인되었으며, 이러한 것은 집단이나 종을 확인할 수 있는 marker로서 활용이 가능할 것이다. 이러한 특이한 primer는 개체, 종 및 집단에서 서로 다른 DNA 다형성을 나타내며, 개체나 집단을 확인하는 데 유용하다는 것을 알 수 있다. 2개 민들조개 집단의 개체들을 비교해 보았을 때 SAMCHEOK no. 03와 WONSAN no. 22에서 가장 긴 유전적 거리(0.696)를 나타내었다. 3개의 genetic groupings and dendrogram을 포함한 complete linkage cluster analysis을 통해서 볼 때 지리적 거리가 있었지만 삼척과 원산 2 민들조개 집단의 개체 정체성과 다소 가까운 친척관계를 확인시켜 주었다. 분자적인 표지인자로부터 얻어진 종내 분류와 clustering analyses은 패각 크기, 패각 형태 및 패각 색깔과 같은 형태적인 형질을 기초한 재래적인 종 분류를 지원하고 있다. 따라서 위에서 언급된 바와 같이 RAPD 분석은 VCS 민들조개 집단이 VCW 집단과 어느 정도 차이가 있다는 것을 확인시켜 주었다.

• 한국패류학회지
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• 제20권1호
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• pp.27-34
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• 2004

Based on both field and laboratory experiments, seasonal changes in the species composition and abundance of phytoplankton in the gut contents of the jedo venus clam, Protothaca jedoensis, and its feeding selectivity were investigated. The phytoplankton in the gut contents comprised Bacillariophyceae (diatom), Chlorophyceae, Chrysophyceae, and Dinophyceae, of which the diatoms being the most predominant throughout the year. Although the number of species and the abundance of phytoplankton in the sea water were always more diverse and more abundant than in the gut contents, the relative number and abundance were generally similar in the seawater and in the gut contents. In the laboratory experiments, the relative abundances of Coscinodiscus marginatus and Thalassirosira eccentrica were much more higher in the gut contents than any other algal species, while Paralia sulcata, Skeletonema costatum, and Eucampia zodiacus were abundant in order of cell density in the ambient water. These results suggest that P. jedoensis may feed preferably on single algal cell or smaller chains of algal cells.

• 한국수산과학회지
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• 제36권5호
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• pp.463-468
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• 2003

This study observed change of survival rate, activity and foot structure of the equilateral venus (Gomphina veneriformis) exposed to cadmium. Survival rate and activity of the clam exposed to cadmium was reduced with increase of exposure duration and concentration. Change of survival rate and activity was observed in the early exposure time (7 days) in the condition of above 1 77 mg/L and 0.88 mg/L, respectively. Activity reduction of the clam exposed to cadmium seems to be caused by epidermal layer deformation, muscle fiber fragmentation and muscular layer collapse of the foot.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.497-498
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• 2000

The venus clam, Ruditapes philippinarum, is an aquaculture shellfish mainly distributed in an intertidal zone of East Asia including Korea, China and Japan. The morphological variation of this species is great. In fact, two of the most popular markers used in molecular evolution, mitochondrial DNA (mtDNA) and nuclear ribosomal DNA (rDNA), have quite different properties, which could translate into different consequences of mutation, drift, migration and selection on patterns of geographical variation and molecular divergence. (omitted)

• 한국가정과교육학회지
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• 제12권2호
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• pp.47-64
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• 2000

The purpose of this study was to search the calcium and iron rich foods in Korean people. The food sources presented in the current home economics textbooks of middle and high school were investigated. And 40 kinds of calcium and iron rich foods were selected by the quantity in 100g edible portion. one serving size and according to 1997 food supply data. Also 3 major food groups of calcium and iron supply in Korean were identified, and 10 rich foods for each food groups were selected. The results were summarized as follows. 1. The food sources of calcium 1) The food sources of calcium presented in the home economics textbooks of middle and high school are milk and dairy products. small fishes such as anchovy icefish and dried strip and green vegetables etc. 2) The calcium rich foods by 100g edible portion were in order of skim milk powder river snail sesame sea mustard. whole milk powder. snapping turtle loach sea tangle(dried) opossum shrimp and sea lettuce(dried). And the calcium rich foods by the calcium content in one serving were in order of river snail snapping turtle opossum shrimp loach spiny lobster skate skim milk powder small alaska pollack freshwater crab condensed milk whole milk powder skate ray and milk. 3) The 3 major calcium supply food groups in Korean were vegetables fish and shellfishes and milk and dairy products. 4) The calcium supply foods according to the quantity of food supply in 1997 was in order of sea mustard, milk anchovy chinese cabbage soybean skin milk powder laver shrimp welsh onion and maize. The vegetables were the important sources of calcium in Korean. 2. The food sources of iron 1) The food sources of iron which are commonly presented in the textbooks of middle and high school were meat liver egg(egg yolk) and green vegetables etc 2) The iron rich foods on the basis of the iron content in 100g edible portion were in order of surf clam marsh clam laver(dried)( sea lettuce(dried), crayfish pelilla seed little neck clam orient hard clam, venus clam, and freshwater carab. And the iron rich foods by the iron content in one serving were in order of surf clam marsh clam crayfish little neck clam orient hard clam freshwater crab venus clam hen cockle green confertii(fresh) pen shell and spiny lobster. 3) The 3 major iron supply food groups in Korean were cereals an cereal products fishes and shellfishes and vegetables. 4) The iron supply food according to the quantity of food supply in 1997 was in order of soybean sea mustard maize rice meat edible viscera laver wheat flour, pook, red pepper, egg and bovine meat.

• 한국수산과학회지
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• 제36권4호
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• pp.352-357
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• 2003

Gonadal development and gametogenic cycle of the equilateral venus, Gomphina collected in the coastal waters of Gangneung, Gangwon-do, Korea were investigated by means of histological method from March 2001 to February 2002. Sex of the clam was dioecious. The gonads are composed of a number of gametogenic follicles. The gonad index (GI) was reached the maximum in June (3.87), and the minimum in August (0.66). The condition index (CI) was reached the maximum in May (0.051), and the minimum in January (0.028). The gametogenic cycle of the clam could be divided into five stages inactive (September to November), early active (November to March), late active (April to May), ripe (June and July) and spent/degenerative stage (July to August). Sex ratio (male/female) was 1:0.9.