• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
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• pp.110.3-110
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• 2000

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• Parasites, Hosts and Diseases
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• 제54권1호
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• pp.109-112
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• 2016

We performed a molecular genetic study on the sequences of 18S ribosomal RNA (ITS1 region) gene in 4-day-old adult worms of Macroorchis spinulosus recovered in mice experimentally infected with metacercariae from crayfish in Jeollanam-do Province, Korea. The metacercariae were round, $180{\mu}m$ in average diameter, encysted with 2 layers of thick walls, but the stylet on the oral sucker was not clearly seen. The adult flukes were oval shape, and $760-820{\mu}m$ long and $320-450{\mu}m$ wide, with anterolateral location of 2 large testes. The phylogenetic tree based on ITS1 sequences of 6 M. spinulosus samples showed their distinguished position from other trematode species in GenBank. The most closely resembled group was Paragonimus spp. which also take crayfish or crabs as the second intermediate host. The present study is the first molecular characterization of M. spinulosus and provided a basis for further phylogenetic studies to compare with other trematode fauna in Korea.

• Journal of Animal Science and Technology
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• 제56권5호
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• pp.16.1-16.9
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• 2014

Fatty acids (FA) have recently been used in several studies to infer the diet in a number of species. While these studies have been largely successful, most have dealt with predators that have a fairly specialized diet. In this paper, we used FA analysis as a tool to infer the diet of the nearctic river otter (Lontra canadensis). The river otter is an opportunistic predator known to subsist on a wide variety of prey including, fishes, crayfish, molluscs, reptiles and amphibians, among others. We analyzed the principle components of 60 FA from otters and 25 potential prey species in Illinois, USA. Prey species came from 4 major taxonomic divisions: fishes, crayfish, molluscs and amphibians. Within each division, most, but not all, species had significantly different profiles. Using quantitative FA signature analysis, our results suggest that, by mass, fish species are the most significant component of Illinois River otters' diet ($37.7{\pm}1.0%$). Molluscs ranked second ($32.0{\pm}0.8%$), followed by amphibians ($27.3{\pm}4.3%$), and finally, crayfish ($3.0{\pm}0.6%$). Our analysis indicates that molluscs make up a larger portion of the otter diet than previously reported. Throughout much of the Midwest there have been numerous otter reintroduction efforts, many of which appear to be successful. In regions where mollusc species are endangered, these data are essential for management agencies to better understand the potential impact of otters on these species. Our analysis further suggests that quantitative FA signature analysis can be used to infer diet even when prey species are diverse, to the extent that their FA profiles differ. Better understanding of the otter's metabolism of FA would improve inferences of diet from FA analysis.

• 한국양식학회지
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• 제22권1호
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• pp.16-22
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• 2009

한국산 가재 Cambaroides similis 자연 개체군의 생활사를 밝히기 위해 2006년 3월부터 10월까지 약 8개월간 서울소재 관악산에 서식하는 가재를 조사하였다. 조사기간 중 포획 및 재포획 방법을 사용하여 총 551개체에 대한 조사가 이루어 졌다. 연구결과 관악산의 가재 개체군은 체장 빈도 분포를 통해 4개의 연령 구조를 가지는 것으로 추정되며, 암수 성비는 거의 동일하였다. 성장률은 수은에 크게 영향을 받음을 알 수 있었다. 6월에 확인된 어린 유생들은 8월에 성체로 성장하였다. 논란이 있었던 한국산 가재의 교미시기는 늦은 가을부터 시작됨을 확인하였다.

• Journal of Ecology and Environment
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• 제48권3호
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• pp.214-221
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• 2024

Background: To identify and avoid predators, amphibians rely on chemical cues. Onychodactylus koreanus undergo two to three years of the larval stage in mountainous streams, where they encounter various predators. We aimed to identify the potential predators of O. koreanus larvae based on their antipredator responses to predator odors. Additionally, we examined whether the response was innate or can be strengthened by predator olfactory learning. Results: In Experiment 1, O. koreanus larvae exhibited a substantial antipredator response to Chinese minnow (Rhynchocypris oxycephalus) odor but not to Korean freshwater crayfish (Cambaroides similis) odor. In Experiment 2, O. koreanus larvae, who did not previously expose to R. oxycephalus odor, demonstrated a substantial antipredator response to it. Experiment 3 indicated that predator olfactory learning of R. oxycephalus did not enhance the antipredator response of the larvae. Conclusions: Rhynchocypris oxycephalus could prey on O. koreanus larvae, whose antipredator response to R. oxycephalus odor is innate and not enhanced by olfactory learning. Further investigation into the olfactory system of this species may provide insights into the life cycle of O. koreanus, uncovering hidden underground breeding sites and unknown breeding periods.

• Parasites, Hosts and Diseases
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• 제23권1호
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• pp.102-110
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• 1985

경북 청진군에서의 폐흡충 침윤상을 알아보기 위해 1984년 3월부터 10월까지 폐흡충의 제 1중간숙주, 다슬기와 분포상과 이들 다슬기에서의 폐흡충 유미유충의 기생상, 제2중간숙주, 가재에서의 본충 피낭유충 기생상 및 주민들에서의 폐흡충 감염상을 조사하였다. 청진군에서 7개지역의 다슬기 서식처를 발견하였으며, 이들 서식처에서의 다슬기의 분포밀도는 하서 Im2당 5∼25개, 평균 15개였으며, 이들 다슬기에서의 폐흡충 유미유충의 기생률은 매우 낮아 0.0152%였다. 폐흡충의 제2중간숙주, 가재에서의 본충 피낭유충 검출률은 18.7%(604마리중 113마리)였으며, 이중 두천계곡에서는 39.0%로 가장 높았으며, 그 다음은 소광계곡(21.6%), 구산계곡(5.9%) 순이었다. 청진군 주민 819명에서의 폐흡충 감염률은 25.8%였으며, 성별 감염률에 있어서 남성은 30.8%, 여성은 19.9%로써 남녀간의 유의적 차를 인정할 수 있었다(t>2). 연령군별 감염률에 있어서는 0∼9세 18.9%로 시작하여 연령이 많아질수록 그 율이 점차로 증가하여 30∼39세 군에서 37.5%로 최고치를 나타내었다. 이상의 성적으로 미루어 보아 경북 소진군에서는 폐흡충 유행지역으로 남아있을 뿐만 아니라, 주민들에서의 폐흡충감염률은 아직도 높음을 알았다.

• 농촌의학ㆍ지역보건
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• 제4권1호
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• pp.71-80
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• 1979

Paragonimiasis is a common trematodiasis of medical importance and one of public health problems in many areas of sob thern part of Korea. During the last sixty years, several on the prevalence among the Korean population have been carried out by various investigators, although the general distribution and prevalences of paragonimiasis are now yet clearly determind. This study was undertaken to evaluate the status of human paragonimiasis in Kang Hwa Gun, Kyung gi Province, Korea by the use of intradermal screening test whih Veronal buffered saline antigen. A total number of 208 residents (male 119, female 89) of all age group in Kilgeong-Ri, Yangdo Myun, Kang Hwa Gun were examined by the intradermal test with paragonimus antigen. The infestation rate of crayfish with Paragonimus metacerearia was also examine in Konneung and Jeoungha village, Kilgeong-Ri from March 1973 to October 1978 by the interval of two to five years. 1. In the resnlt of 208 residents, Kilgeong-Ri, the positive rate showed in 29.3% in as a whole(36.1% in male, 20.2% in female). The highest positive rate showed in 10 to 19 age group(41.5%). 2. Among the residents in Kilgeong-Ri, Paragonimus eggs were detected in 11 residents by the sputum and the stool examinations without the intradermal test result. 3. The infestation rate of crayfish with Paragonimus inetacercaria was 90.6%(116 out of 128 crayfishes) in Konneung village, and 61.5%(24 out of 39) crayfishes) in Jeongha village, Kilgeng-Ri. 4. The fluctation of the infestation tate and density of crayfish with Paragonimus metacercaria was decreased by the interval of two to five years in Konneung and Jeongha village in Kilgeong-Ri.

• Parasites, Hosts and Diseases
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• 제34권1호
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• pp.1-6
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• 1996

강원도 양양군 현북면 어성전리에 서식하는 참가재(Cambaroines simiLis)의 근육에서 Marroorchis spinulosus Ando. 1918(Digenea: Nanophyetidae)의 피낭유충을 검출하고 마우스 흰쥐 및 고양이에 실험감염시켜 성충을 얻은 다음 형태학적 특징을 관찰하였다. 실험동물 들의 소장으로부터 감염 5-21일에 총 117마리의 충체를 회수하였으며. 평균 충체회수율은 31-37%로서 동물별로 큰 차이가 없었다. 피낭유충은 등글고. 평균 직경 0.18 mm이며. 2개의 두꺼운 막으로 둘러싸여 있고. Y-자형의 배걸낭을 가지고 있었다. 성충은 대부분 난형이며 길이 0.66-0 71 mm. 폭 0.36-0.41 mm이었다. 구흡반에는 침(stylets) 1개가 있고. 난소가 체중앙부 근처에서 다양하게 위치하며. 저정낭이 이낭형(bilobed)이고 두 고환이 약간 전측방에 위치하는 점 등의 형태학적 특성을 나타내었다. 실험 감염에서 얻은 성충들을 M. spinulosus로 동정할 수 있었으나 그 형태가 최초 기록과 몇 가지 다른 점이 있어 앞으로 이 흡충의 원환한 진단을 위왜 충체의 형태를 수정하여 재기록하였다 이 장흡충푸 국내에는 미 기록종이며 포유동물을 종숙주로 하고 있을 것으로 추측되며 인체 감염 가능성도 배제할 수 없다. 이 충체의 우리발 이름을 가시큰고환흡충으로 부를 것을 제안한다.

• 농촌의학ㆍ지역보건
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• 제6권1호
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• pp.5-12
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• 1981

Paragonimus infection is prevalent in Korea, establishing several endemic foci. Kim(1969) reported an endemic area in Hyeonbuk Myeon. Yangyang-Gun, but thereafter no further epidemiologic study of Paragonimus infection was performed in the Gangweon-Do. Hoengseong-Gun is mountainous area which is located in the southwestern part of Gangweon-Do and borders with Hongcheon-Gun on the east, with Pyeongchang-Gun on the east, with Yeongweol-Gun and Weonseong-Gun on the south, and with Yangpyeong-Gun on west. The author carried out an epidemiologic study of Paragonimus infection by intradermal test with V.B.S antigen, and of intermediate host (crayfish) in Hoengseong-Gun, Gangweon-Do. The results are summarized as follows: 1. The positive skin test reaction to Paragonimus antigen was 14.5% from 2,807 examiness; 16.0% in male and 11.6% in female and no sex or age difference on the skin test positive reactions was noticed among the villages. 2. The positive skin test reactions were 31.3% in Gapcheon-Myeon, 20.5% in Cheongil-Myeon and 19.8% in Woocheon-Myeon. Primary school children in Byeongjibang-ri, Gapcheon-Myeon showed positive in 36.4%. 3. The prevalence by skin test reaction by social strata was 16.1% (226 out of 1,408) in primary school children, 12.8% out of 725) in middle school, 6.4% (11 out of 172) in high school students, and 15.3% (77 out of 502) in inhabitants of Heongseong-Gun. 4. Metacercarial positives of Paragonimus in crayfish were 20.9%. Through the survey results, it is postulated that Heongseong-Gun, Gangweon-Do is to be categorized as an endemic area of Paragonimus infection.

• Journal of Species Research
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• 제5권3호
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• pp.459-462
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• 2016

The branchiobdellidan species Holtodrilus truncatus (Liang, 1963) is reported for the first time in Korea. The genus Holtodrilus Gelder and Brinkhurst, 1990 is monotypic within the family Xironodrilidae, and the genus and family of this species are also new to the Korean fauna. The branchiobdellidan specimens were collected from the exoskeletons of the freshwater atyid shrimp, Neocaridina sp., sampled from the 'Andeok Valley', Jeju-do Province, South Korea. Holtodrilus truncatus is characterized by its terete body form, 7/7 dental formula (with a large medial tooth and three pairs of smaller lateral teeth), and no trunk appendages. In addition, we determined a partial sequence of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene as a DNA barcode marker for H. truncatus. The present study is the first record of the branchiobdellidan occurrence on a non-crayfish host (shrimp) in Korea. To date, seven species (four genera in three families) of branchiobdellidans have been reported in the Korean fauna.