• Parasites, Hosts and Diseases
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• v.28 no.4
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• pp.221-234
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• 1990

The present study was performed to know the epidemiological statug of echinostomiasis in the Chungju Reservoir and upper streams of Namhan River, together with an experimental study on the life history o( Echinostoma hortense. The stool specimens of 169 inhabitants and 473 junior high school students from 5 different villages revealed 3(0.5%) echinostomatid egg Positive cases. E. hortense adult worms were recovered from one patient after a treatment and purgation. For the other two patients, it was presumed that one had 2. hortense and another E. cinetorchis infection, based on the morphology of eggs. Five kinds of freshwater snails(168 Radix auricularia coreane, 534 Physa arutp, 144 Hippeutis cnntori, 56 Cipcngopaludina chinensis malleata and 125 Semiiulcospira nediila glebus) examined for the cercariae of echinostomes showed negative results. Ten kinds of freshwater fishes examined for E. herten-'emetacercariae revealed positive rates as Misgurnus anguillicaudatus 40.5%, Odentobutis obscura interrupta 20.3%, Moroco onycephalus 3.9%, and Coreoperca hawamebari 2.0%. In the experimental study, the metacercariae of E. horlense were infected to rats, eggs were collected from adult worms and cultivated, and miracidia were obtained. The miracidia were artificially infected to freshwater snails (R. auricularia), and cercarial shedding was studied. It was revealed that, when the snails were kept at a low temperature ($24^{\circ}C$), only 523 cercariae (on average) were produced during 24 hrs, while they were at a high temperature ($30^{\circ}C$), as many as 9, 990 cercariae (on average) were shed during the same time. The experimental infection of E. hortense cercariae to freshwater fishes was successful in 0. obscura interrupta 52.0%, M. anguillicaudatus 30.3%, C. kawamebari 27.0%, Cobitis lutheri 15.0%, M. cxycephazus 7.3%, Pseudogobio esocinus 4.3%, Squalidus cereanus 2.0%, Zccco platypus 1.3%, and Pungtungia herzi 1.3%. However, infection was not successful to snails, C. chinensis. It has been proved that the Chungju Reservoir and upper streams of Namhan riyrr are endemic areas of echinostomiasis, especially of E. horfense, and snails such as R. auritulerie coreana and fishes such as O. obscura interrupts, M. gnguillicgudgtus, and others are taking the role of 6rst and second intermediate hosts, respectively.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.11a
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• pp.201-205
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• 2001

설악산 국립공원지역 산간계류의 17지점에서 2000년 6월부터 2001년 6월까지 어류상 및 이화학적 요인 분석을 실시하였다. 모든 조사지점은 1-3차 이내의 하천으로 비교적 물리ㆍ화학적 교란이 적었으며 하천폭은 5～30 m 정도였다. 채집된 어류는 총 17과 42종 2,557개체였고, Cyprinidae는 16종 2,165개체가 채집되어 84.7%의 상대풍부도를 나타냈으며, Cobitidae는 5종으로 Cyprinidae 다음으로 가장 많은 종이 채집되었으나 개체수는 109개체로 4.2%의 상대풍부도를 보였다. Gobiidae가 4종 (5.0%), Salmonidae는 모두 3종 (0.8%)이 채집되었다. 이외에도 Oryziatidae, Plecoglossidae, Amblycipitidae, Cottidae, Serranidae 등 12과는 각각 1종씩 모두 117개체 (4.6%)가 채집되었다. Cyprinidae는 전체 채집종의 37.2%를 나타냈다. 우점종은 Zacco temmincki로 10개 지점에서 738개체가 채집되어 28.9%의 상대풍부도를 나타냈으며, 아우점종은 Moroco kumtangensis와 Z.platypus로 각각 4개 지점 648개체 (25.3%)와 7개 지점 344개체 (13.5%)로 나타났다. 한국고유종 (Korean endemic species)은 모두 4과 11종 781개체로 30.5%의 상대풍부도를 나타냈으며, 고유화 빈도는 25.6%로 한국의 평균 고유화 빈도와 유사하게 나타났다 우점종은 M. kumkangensis (한국고유종 중 83.1%)로 나타났으며, 아우점종은 Coreoperca herzi (5.8%), Microphysogobio longidorsalis (3.8%)와 Coreloeuciscus splendidus (2.6%)로 나타났다. 본 조사에서 외래어는 채집되지 않았다. 어류의 다양성은 국립공원내에서보다 하천폭이 커지고 서식처자 비교적 다양한 경계지역의 하천 조사지점에서 더 높게 나타났다.따라서 국립공원의 경계지역에 대한 효율적인 생태적 관리가 요구되며, 국립공원 내의 어류의 다양성 유지와 회복을 위해서는 공원 내는 물론 경계지역 산지하천의 물리적 변형 (보, 제방, 석축 등)과 오염원의 유입 (점, 비점오염원)에 대한 고려가있어야 한다.

• Journal of Environmental Science International
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• v.10 no.3
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• pp.225-231
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• 2001

The fish species collected in the Keumho River basin are 42 species 31 genera belonging to 15 Families. This report was investigated for the evaluation of water quality in the Keumho River system which is a tributary of Nakdong River in Korea on september in 1999. The fishes collected were 42 species, 31 genera belonging to 15 Families. The dominant species were 5 species; Zacco platypus, Zacco temmincki, Squalidus chankaensis tsuchigae, Moroco oxycephalus, Squalidus gracilis majimae, and 8 species; Hemibarbus longirostris, Pseudogobio esocinus, Culter brevicauda, Cobitis rotundicaudata, Pseudobagrus fulvidraco, Pungitius sinensis kaibarae, Monopterus albus, Channa argus were rare species. The relationship among the GPI, EC and BOD by the organic pollutants were over 0.9. The group pollution index(GPI) was lowest at St. 1(0.85) and highest at St. 1(0.85) and highest at St. 5(2.33). The water quality of the Keumho river divided into 3 parts; the water of upper reaches in river(St. 1) was 1st class(oligotrophic condition), middle parts(St. 2, 3, 4) were 3rd class($\alpha$-mesosaprobic condition) and lower part(St. 5) was 4th class(Polysaprobic condition) as the source of tap water, respectively. And the tributary which are the Sinryeong Stream(St. 6), the Sincheon(St. 7) and the Donghwa Stream(St. 9) in Keumho river were 2nd class as the source of tap water. The results in this study was represented same patterns as the result by the use of indicator species like as algae and invertebrates for the discrimination of water quality. So, some freshwater fish species can be use applicant for the discrimination of water quality.

• The Korean Journal of Zoology
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• v.16 no.2
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• pp.97-108
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• 1973

Karyological characteristics and relative DNA values were investigated in four species of the family Cyprinidae of Korean fresh-water. The results obtained were as follows; 1) The two Hemibarus species, H. longirostris and H. labeo, had the aiploid chromosome number of 50. The compliment of former consisted of 7 metacentric, 14 submets- and subtelocentric and 4 telo- or acrocentric pairs, whereas latter had 9, 11 and 5 pairs respectively, Total arm numbers (AN) were 92 and 90. 2) In the case of two species of genus Moroce, M. oxycephalus and M. lagowskii, their diploid number and karyotype showed in identical pattern for each other (2n=50); 6 pairs of metacentrics, 14 pairs of submeta- and subtelocentrics and 5 pairs of telo- or acrocentrics. The AN of both species were 90. 3) Relative DNA values of all species were measured as about 60% that of gold fish. From the above observation, the cytogenetical character was discussed with special concern to the phylogenetic significance.

• The Journal of Natural Sciences
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• v.7
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• pp.121-131
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• 1995

Orientalism showed in early 20th century as change of Style. Modern characteristics is understanded through big stream of change before historical conception. Change of style in West began by artist having oriental and exotic taste. These are mimesis of outershape about Japanese, Moroco, north Africa etc. Theses are called chinoiserie & turquise taste. Stream of 20th century style is continued expressionism. Cubism, Sur realism, Pop Art etc. but in my thesis orientalism is caused change of 20th Century after exotism (after showed as Primitivism ). In modern costume, concerned works of Paul Poiret changed body concious. He's a image creator as Yve St. Laurent, Chanel, Balenciaga. At that time Russia Ballet, Fauvist, vivid colors are back ground of series of modern costume. Soft and sleek body, transparent stocking, minaret tunic, turban is begin of oriental image. Modern costume and modern art are begins as change of aesthetic taste before historical conception.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.1
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• pp.35-41
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• 2004

The yeongok stream originates at the natural park, Mt. O-dae and flows to the East Sea of korea, normally maintaining I or II grade of water quality and its average water flux is 352,100 ㎥/d. However, the typhoon 'Rusa', which occured on 31 August 2002, changed its watercourse and configuration, and the ecosystem was deeply damaged. Moreover, the hydrological characteristics were once more transformed, and the ecosystem was secondarily damaged during repair-work of destroyed bridges and elevations. After the flood disaster, the species diversity diminished 17% for attached diatom and 44% for aquatic animals. However, the earth and sand, dug from river bed during intensive repair-work throughout the entire stream, made diversity drop to 32% for the diatom and the aquatic animals were wiped out. Especially, fishes were totally destroyed except for some species such as Moroco oxycephalus in the upper stream. The yeongok stream has little contamination source and short water residence time due to the short length and rapid slope, and consequently a temporary deterioration of water quality caused by repair-work may be rapidly recovered, but it needs a long time to restore the damaged ecosystem.

• Parasites, Hosts and Diseases
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• v.24 no.2
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• pp.121-136
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• 1986

Recently there have been some reports on human infections of Echinostoma hortense in Korea. It was found that a few species of freshwater fishes were playing the role of the second intermediate host of E. hortense. However, molluscan intermediate host has not been identified yet in Korea. The present study aimed to establish the life cycle of E. hortense in laboratory. Experimental studies such as egg production from the rat, development of the eggs in vitro, exposure of miracidia to freshwater snails, shedding pattern of cercariae from infected snails, morphology of cercariae, cercarial infection to the second intermediate host and infection of metacercariae to the definitive hosts were done. In addition, epidemiological surveys on the infection status in inhabitants and house rats, and on the natural infection of larval echinostomes in the snails and fishes were carried out along the South Hangang-river. The results obtained were as follows: 1. The eggs deposited from adults in physiological saline were cultivated at room temperature($20{\sim}24^{\circ}C$). The miracidia were firstly observed on 8 days after cultivation, and 85.5% of the eggs contained the mature miracidia on 11 days after cultivation. More than 90% formed the miracidia when cultivated at temperature $22{\sim}27^{\circ}C$. Hatching of the miracidia began on 12 days after cultivation and continued for a week. The size of the miracidia was $103.0{{\times}}51.4{\mu}m$ in average. The motility of the miracidia were active up to 8 hours after shedding, but they were all dead within 10 hours after shedding. 2. A freshwater snail, Radix auricularia coreana was cultivated in aquaria. A hatched $F_1$ snails from the egg masses were exposed to 20 miracidia respectively. Escape of cercariae started on 15 days after infecton. Radix auricularia coreana was experimentally identified as the first intermediate host of E. hortense in Korea. 3. Cercarial shedding started on $15{\sim}20$ days after infection by snail, continued for about 10 days (8.8 days in average). Infected snails were dead within 32 days after the miracidial infection. About 1,335 cercariae($328{\sim}1,994$) per snail were shed in its life, and 119 cercariae in average per snail per day were shed. The cercariae were motile for more than 24 hours, and then squirming at the bottom until death. The body and tail sizes of cercariae were $356{\times}186{\mu}m$ and $510{\times}68{\mu}m$ in average, respectively. The rediae parasitized in the snail hosts were found mainly around the pericardial regions, and their size was $1,575{\times}258{\mu}m$ in average. The numbers of developing cercariae in a mature redia were 14 in average ($7{\sim}20$ in range). The numbers of rediae in a snail were 102 in average on 15 days after miracidial infection and 221 in average on 28 days. 4. Three uninfected Misgurnus anguillicaudatus, less than 6.5cm long were used in for the cercarial infection. They were all exposed with 755 cercariae, and examined at 5-day intervals starting from 10 days after infection. All the fishes were infected with metacercariae of E. hortense and a total of 275 was found infected(36.4%). The metacercariae were fed to rats and the adult worms were obtained on 15 days after infection. 5. The infected rats began to deposit the eggs on 11 days after infection. The number of eggs deposited per day per worm (EPD/worm) was $400{\sim}500$ on 3 weeks after infection and was increased to $1,000{\sim}1,500$ on 4 to 17 weeks, then decreased to 800 on 21 weeks after infection. 6. A total of 745 stool specimens collected from 576 male and 169 female residents of 8 different villages along South Hangang basin was examined. Out of 745 specimens, the eggs of Echinostoma sp. were found in 2 cases (0.3%). Of 34 house rats one showed egg-positive (2.9%). 7. Total 971 Radix auricularia coreana collected from 7 sampling stations were examined for shedding of cercariae. Three snails (0.3%) shed the cercariae of E. hortense. A total of 119 out of 542 freshwater fishes (22.0%) had the metacercariae of E. hortense. The fishes parasitized with the metacercariae were 4 out of 14 examined species. The infection rates of 4 species were 34.1% (106 out of 311) in Misgurnus anguillicaudatus, 30.4% (7 out of 23) in Misgurnus mizolepis, 4.3% (2 out of 46) in Moroco oxycephalus and 22.2% (4 out of 18) in Odontobutis obscura interrupta. In summarizing the above results, the first intermediate host of E. hortense was found as Radix auricularia coreana in Korea. Also, it took about 46 days for the shortest completion of a life cycle of E. hortense in summer; that is, 10 days for miracidial development in eggs, 15 days for cercarial development in the snail, about 10 days for metacercarial development in the second intermediate hosts, and 11 days for the maturation as the adults in the definitive hosts. The natural infection rates of E. hortense in the intermediate hosts were relatively high but those in the definitive hosts were low in the middle areas of South Hangang basin.

• Korean Journal of Environmental Biology
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• v.17 no.2
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• pp.169-173
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• 1999

The present study was undertaken to survey the infection status of Metagonimus sp. metacercariae in freshwater fishes from Tong river located in Kangwon Province, a total of 178 freshwater fishes of 11 species were collected by a fish net and traps from the end of September to early October 1998. They were brought to the laboratory and examined under a stereomicroscope after artificial digestion with pepsin-HCI solution for one hour. Ten out of eleven species of freshwater fishes examined were found to contain metacercariae of Metagonimus sp. The most frequently infected fish was Liobagrus andersoni Regan 91.7% (11 of 12 fishes), followed by Gobiobotia breviburba Mori 75.0% (6 of 8 fishes), Zacco temmincki 66.2% (49 of 74 fishes), Cobitis koreensis Kim 50.0% (1 of 2 fishes), Microphysogobio longidorsails Mori 42.9% (9 of 21 fishes), Cobitis rotundicudata Wakiya et Mori 33.3% (2 of 6 fishes), Hemibarbus longirostris 33.3% (1 of 3 fishes), Pungtungia tenuicorpus 30.0% (3 of 10 fishes), Coreoleuciscus splenddus Mori 28.6% (4 of 14 fishes), Coreoperca herri Herzeanstein 11.1％ (1 of 9 fishes) respectively Metagonimus metacercariae was not found from Moroco kumgangensis Uchida of freshwater fish. The total number of Metagonimus sp. metacercariae was 81, 17, 216, 1, 14, 2, 1, 4, 10, 1, respectively. Infection rates of Metagonimus sp. in the five districts was shown as follows : Chongson-up Kyulam-ri 50.0% (12 of 24 fishes), Chongson-up Kasu-ri 34.0% (17 of 50 fishes), Shindong-up Unchi-ri 56.0% (14 of 25 fishes), Shingdong-up Kosong-ri 57.1％ (20 of 35 fishes), Shingdong-up Duckchon-ri 54.5% (24 of 44 fishes) respectively. Infection rate of freshwater fish was 48.9% (87 of 178 fishes) and from the results obtained in this survey, it was confirmed that freshwater fishes from Tong river was infected with metacercariae of Metagonimus sp.

• Journal of fish pathology
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• v.33 no.2
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• pp.111-118
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• 2020

The genus Edwardsiella belonging to the family Enterobacteriaceae is a member of Gram-negative rod-shaped bacteria that cause disease in diverse aquatic organisms such as fish, amphibians and reptiles as well as avians and mammals including human throughout the world. This genus had been composed of three species, E. hoshinae, E. ictaluri and E. tarda, but recent researches erected two novel species, E. anguillarum and E. piscicida that were conventionally identified as E. tarda. In this study, we isolated seven strains belonging to the genus Edwardsiella from freshwater fishes that had been reared at inland fish farms in South Korea and investigated their biochemical characteristics and molecular phylogenetic relationships. The seven strains showed typical characteristics of four Edwardsiella species, E. anguillarum, E. ictaluri, E. piscicida and E. tarda, by biochemical analyses of Gram staining, indole and hydrogen sulfide (H2S) production, and API (Analytic Profile Index) 20E test. Molecular phylogenetic analyses inferred from DNA sequence data of both 16S ribosomal RNA (rRNA) and DNA gyrase subunit B (gyrB) genes were congruent with the biochemical characteristics. As a result, both biochemical and molecular phylogenetic analyses identified four strains isolated from three Anguilla species as E. anguillarum, E. piscicida and E. tarda, two strains from Pelteobagrus fulvidraco and Silurus asotus as E. ictaluri, and one strain from Moroco oxycephalus as E. piscicida. In this study, we isolated and successfully identified recently newly erected species, E. anguillarum and E. piscicida in addition to historically notorious pathogenic species, E. ictaluri and E. tarda. In the future study, systematic and comprehensive monitoring of the four Edwardsiella species are required for studying differences in pathogenicity among freshwater fishes.