Distribution of medically important freshwater snails and larval trematodes from <i>Parafossarulus manchouricus</i> and <i>Semisulcospira libertina</i> around the Jinyang Lake in Kyongsang-Nam-Do, Korea

, Cho, Hae Chang; , Chung, Pyung Rim; , Lee, Keun Tae

doi:1983.21.2.193

Korean J Parasito > Volume 21(2):1983 > Article

Original Article


Korean J Parasitol. 1983 Dec;21(2):193-204. English. Published online Mar 20, 1994. http://dx.doi.org/10.3347/kjp.1983.21.2.193
Copyright © 1983 by The Korean Society for Parasitology


Distribution of medically important freshwater snails and larval trematodes from Parafossarulus manchouricus and Semisulcospira libertina around the Jinyang Lake in Kyongsang-Nam-Do, Korea
Hae-Chang Cho,Pyung-Rim Chung and Keun-Tae Lee
Department of Parasitology, College of Medicine, Yonsei University, Korea.



Abstract
The Jinyang Lake is dammed up Nam River, and surrounded by Jinju city and four counties; Jinyang, Sanchong, Hadong, and Sachon in Kyongsang-Nam-Do, Korea. The area around this man-made lake have been known as an endemic focus of clonorchiasis in Korea. The present study was first aimed to know the distribution of freshwater mollusks including medically important snails, and larval trematodes shed from Parafossarulus manchouricus and Semisulcospira libertina. In addtion to above studies, water analyses in each snail habitat were carried out in order to figure out a part of their environmental factors. This malaco-ecological survey was done at the six areas around upper, middle and lower parts of the lake for 4 months, August-November, 1983. Total nine species of freshwater mollusks were collected throughout the study: 4 species of gastropods; Semisulcospira libertina, Cipangopaludina chinensis, Parafossarulus manchouricus and Radix auricularia, and 5 species of bivalves; Unio douglasiae, Anodonta woodiana, Lamprotula gottschei, Corbicula fluminea and Limnoperma lucustris. Out of nine species of freshwater mollusks, three species of gastropods; S. libertina, P. manchouricus and R. auricularia were medically important in terms of the transmission of digenetic trematodes to humans. P. manchouricus and R. auricularia were mainly collected from the shallow ponds and the irrigation channels with the muddy basin, but S. libertina and the bivalves were only collected from the stream of Nam river where the gravels and rocks were dominant. The levels of dissolved oxygen(D.O.) and biochemical oxygen demand (B.O.D.₅) of the water specimens sampled from the study areas ranged from 6.0 to 9.6 ppm and from 0.4 to 1.6 ppm respectively. As a result, it is considered that water system around the Jinyang Lake might be relatively clean without any heavy pollution of aquatic microorganisms and organic materials during the period of this study. On the other hand, eight metalic constituents from the water samples were also assayed, and all metalic ions detected were remarkably low below the legal criteria. However, calcium ion in the water samples from the habitats of P. manchouricus was considerably higher than others. Infection rates of digenetic trematodes in the snails were 6.9% in P. manchouricus and 4.8% in S. libertina, respectively. P. manchouricus snails harboring with the cercariae of Clonorchis sinensis were only 0.14% among the snails examined and other trematode cercariae except cercaria of C. sinensis were; furcocercus cercariae, cercaria of Loxogenes liberum type I and II. S. libertina snails parasitized with the cercariae of Metagonimus yokogawai were 1.5% out of the snails examined and no cercaria of Paragonimus westermani was found in S. libertina snails in the present study. Digenetic trematode cercariae other then M. yokogawai in S. libertina snails were: Cercaria yoshidae (B type), Cercaria cristata, Cercaria innominatum, Cercaria of Centrocestus formosanus and Cercaria nipponensis.

Figures


	Fig. 1 Map of the Jinyang Lake, Kyongsang-Nam-Do, depicting collection sites.


	Fig. 2 Cercariae shed from Parafossarulus manchouricus. 1. Cercaria of Clonorchis sinensis (100×) 2. Furcocercus cercaria (Family Sanguinicolidae) (100×) 3. Cercaria of Loxogenes liberum, type I(100×) 4. Cercaria of Loxogenes liberum, type II(100×)


	Fig. 3 Cercariae shed from Semisulcospira libertina. 1. Cercariae of Metagonimus yokogawai (100×) 2. Cercariae yoshidae, B type (200×) 3. Cercariae cristata (100×) 4. Cercariae innominatum (100×) 5. Cercariae of Centrocestus formosanus (100×) 6. Cercariae nipponensis (100×)


	Fig. 4 Freshwater gastropods collected around the Jinyang Lake. 1. Semisulcospira libertina 2. Parafossarulus manchouricus 3. Cipangopaludina chinensis maleata 4. Radix auricularia coreana


	Fig. 5 Freshwater bivalves collected around the Jinyang Lake. 1. Unio douglasiae 2. Lamprotula gottschei 3. Limnoperma lucustris 4. Corbicula fluminea 5. Anodonta woodiana

Tables


	Table 1 Species of mollusks collected at the Jinyang Lake areas


	Table 2 Monthly observations of trematode cercariae shed from Parafossarulus manchouricus (Dae-Pyong, Hoi-Byong, Omi)


	Table 3 Incidences of larval flukes shed from Parafossarulus manchouricus (Dae-Pyong, Hoi-Byong, Omi)


	Table 4 Monthly observations of trematode cercariae shed from Semisulcospira libertina (Dam Area)


	Table 5 Incidences of larval flukes shed frm Semisulcospira libertina (Dam Area)


	Table 6 pH values and temperature (℃) of waters at the collecting areas of Jinyang Lake in August, 1983


	Table 7 D.O and B.O.D₅ values of waters at the collecting areas around Jinyang Lake in August, 1983


	Table 8 Chemical analysis of waters in which the mollusks were collected at the Jinyang Lake areas in August, 1983

References


1.	Choi DW, Chung BJ. Clonorchis sinensis in Kyungpook Province, Korea: 1. Distribution and demonstration of the cercaria of Clonorchis sinensis from snail, Parafossarulus manchouricus Bourgigant. Korean J Parasitol 1975;13(2):133–138.

2.	Choi DW, Ahn DH, Kim HS. Larval Trematodes From Semisulcospira Snails In Kyungpook Province, Korea. Korean J Parasitol 1982;20(2):147–159.

3.	Hamajima F, Ishii Y. Studies On The Host-Parasite Relationship Of Paragonimus Westermani (Kerbert, 1878). I. Incidence Of Cercariae In The Snail Host, Semisulcospira Bensoni (Philippi) At Some Different Localities. Kyushu J Med Sci 1963;14:189–194.

4.	Han JS, et al. Bulletin of Pusan Fisheries Coll 1963;5:39–44.

5.	Hirose H. J Chosen Med Assoc 1913;4:105–106.

6.	Kim CH, et al. Korean J Parasit 1981;19:191–192.

7.	Kobayashi H. J Chosen Med Assoc 1918;21:19–80.

8.	Kobayashi H. Dobutsugaku Zasshi 1922;34:252–270.

9.	Kwon OK, et al. Korean J Limnol 1979;12:25–33.

*10.*	Miyazaki I. Thoracic Diseases 1961;5:953–962.

*11.*	Muda N. Okayama Med J 1913;287:15–32.

*12.*	Soh CT. Yonsei Rep Trop Med 1978;9:1–10.