In vitro excystation of metacercarial cysts of Echinostoma trivolvis from Rana species tadpoles

Original Article


Korean J Parasitol. 1997 Jun;35(2):75-77. English. Published online Jun 20, 1997. http://dx.doi.org/10.3347/kjp.1997.35.2.75
Copyright © 1997 by The Korean Society for Parasitology


In vitro excystation of metacercarial cysts of Echinostoma trivolvis from Rana species tadpoles
B Fried,^* and J D Bradford
Department of Biology, Lafayette College, Easton, PA 18042, USA.

Received April 20, 1997; Accepted May 27, 1997.
Abstract
In vitro excystation studies were done on the metacercarial cysts of Echinostoma trivolvis obtained from the kidneys of naturally infected Rana species tadpoles. Cysts were excysted in an alkaline trypsin-bile salts medium and the percentage of excystation was compared with that from previous studies done on cysts obtained from the kidneys of snails. The percentage of excystation of E. trivolvis metacercariae from tadpole kidneys was similar to that reported for previous studies on cysts obtained from experimentally infected gastropod hosts. The possible role of tadpoles as an agent for the transmission of Echinostoma and echinostomiasis to humans is discussed.

Tables


	Table 1 Incidence of infection of Echinostoma trivolvis cysts in randomly selected Rana species tadpole kidneys


	Table 2 Percentage excystation of Echinostoma trivolvis metacercarial cysts from tadpole kidneys

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