• Parasites, Hosts and Diseases
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• v.28 no.4
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• pp.235-240
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• 1990

During an investigation on intestinal flukes of house rats in Yangyang-gun, Kangwon-do, a total of 6 species of trematodes belonging to 3 families; Echinostom-atidae (Echinostoma hortense, E. cinetorchis, E. revolutum and Echinoparyphium recurvatum), Diplostomidae (Fibricoza seoulensis) and Plagiorchiidae (Plagiorchis muris), were recovered from two adult rats. E. revolutum and E. recurvatum were new trematode faunae of rats in Korea. 5. revolutum had an elongated body, 5.3∼6.Omm long and 1.0∼1.3mm wide. The total number of collar spines was 35∼37 including 5 end group ones on each ventral corner. Its coiled uterus contained numerous eggs.5. recurvatum also had an elongated body, 3.5∼4.7 mm long and 0.50∼0.65 mm wide. It had total 45 collar spines including 4 end group ones. The uterus toras short with only a few eggs. It has been first confirmed by this study that E. revolutum and E. recurvatum are indigenously distributed among house rats in Korea. Kef lords: Echinostoma revolutum, Echinoparyphium recurvatum. new fauna. house rats, Yangyang-gun ( Kangwon-do )

• Parasites, Hosts and Diseases
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• v.51 no.6
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• pp.663-667
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• 2013

Free-grazing ducks play a major role in the rural economy of Eastern Asia in the form of egg and meat production. In Thailand, the geographical location, tropical climate conditions and wetland areas of the country are suitable for their husbandry. These environmental factors also favor growth, multiplication, development, survival, and spread of duck parasites. In this study, a total of 90 free-grazing ducks from northern, central, and northeastern regions of Thailand were examined for intestinal helminth parasites, with special emphasis on zoonotic echinostomes. Of these, 51 (56.7%) were infected by one or more species of zoonotic echinostomes, Echinostoma revolutum, Echinoparyphium recurvatum, and Hypoderaeum conoideum. Echinostomes found were identified using morphological criteria when possible. ITS2 sequences were used to identify juvenile and incomplete worms. The prevalence of infection was relatively high in each region, namely, north, central, and northeast region was 63.2%, 54.5%, and 55.3%, respectively. The intensity of infection ranged up to 49 worms/infected duck. Free-grazing ducks clearly play an important role in the life cycle maintenance, spread, and transmission of these medically important echinostomes in Thailand.

• Parasites, Hosts and Diseases
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• v.40 no.2
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• pp.67-73
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• 2002

The present study was performed to observe tegumental ultrastructure of Echinoparyphium recurvatum according to developmental stages. Worms (1, 3, 5 and 15-day old) were recovered from chicks experimentally infected with metacercariae from radix auricularia coreana. One-day old worms were elongated and ventrally concave, and covered with peg-like tegumental spines except the adjacent areas of the head crown and excretory pore. Type I sensory papillae were distributed on the lip of the oral sucker, and grouped ciliated papillae were around the oral sucker. Peg-like tegumental spines were densely distributed on the anterior surface of the ventral sucker level. The ventral sucker had an aspinous tegument and no sensory papillae. Tegumental spines on the posterior surface of the ventral sucker level were sparsely distributed and disappeared posteriorly. In 3 and 5-day old worms, the tegument around the oral sucker was aspinose and wrinkled concentrically. The ventral sucker had a wrinkled tegument and many bulbous papillae. Type I sensory papillae were distributed between the bulbous papillae. Tegumental spines were spade-shaped with a terminal tip. A total of 45 collar spines including 4 end group ones on both ventral corners was alternately arranged in 2 rows. The 15-day old worms were very stout and their tegumental spines were tongue-shaped without a terminal tip, From the above results, it is confirmed that the surface ultrastructure of E. recurvatum was generally similar to that of other echinostomatid flukes. However, some features, i.e., morphological change of tegumental spines and appearence of sensory papillae on the ventral sucker according to development, and number, shape and arrangement of collar spines, were characteristic, which may be of taxonomic and bioecological significance.

• Parasites, Hosts and Diseases
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• v.36 no.2
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• pp.91-98
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• 1998

The present study was performed to observe characteristics of the lifE history of Echinoparvphium recunpatum under both natural and laboratory conditions in Korea. A batch of Rcnix aunculnria corecna was collected from Sunamchon, one of the stream of West Naktonggang (River), in Kangso-gu, Pusan during August and September 1992. Out of 106 snails examined by crushing,52 (49.0%) were infected with larval E. recurvaum i.e. rediae, cercariae and metacercariae. Cercariae naturally shed from snails encysted in the snails of same species and loaches, but not in mud-snails. Adult worms were detected from chicks and ducks experimentally infected with metacercariae, but not from rats and mice. The average recovery rate of adults from chicks was 13.1%. Rediae were sac-like, $2.437{\;}{\times}{\;}0.317{\;}mm$ in average size, with a muscular pharynx and a brownish cecum which reached the anterior half of the body. Cercariae consisted of a spindle-shaped body ($0.262{\;}{\times}{\;}0.129{\;}mm$ in average) and a rod-like tail ($0.528{\;}{\times}{\;}0.056{\;}mm$ in average). In the cercarial body, 45 collar spines were observed on the head crown, and double rows of excretory ducts with fine granules were laterally arranged between the pharynnx and the ventral sucker. Metacercariae were spherical, $0.144{\;}{\times}{\;}0.142{\;}mm in average size, with thick hyaline outer and thin elastic inner walls, and many excretory granules. Adults were slender and more attenuated in the anterior end, $0.2760{\;}{\times}{\;}0.550{\;}mm$ in average size, and had 45 collar spines including four end group spines on both ventral corners. From the above results, it was confirmed that R. auriculnna corennc plays a pivotal role in the life cycle of 5. recuwatum as the first and/or second intermediate hosts in Korea.