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Dynamics of the intramolluscan larval development of Schistosoma haematobium: replication of daughter sporocysts and cercarial production

Published online by Cambridge University Press:  05 June 2009

N. Kechemir
Affiliation:
Service de Parasitologie, Institut Pasteur d'Algérie, Rue du Dr. Laveran, Alger, Algeria
A. Théron
Affiliation:
Laboratoire de Biologie Animale, UA CNRS n° 698, Centre de Biologie et d'Ecologie tropicale et méditerranéenne, Université, Av. de Villeneuve, 66025 Perpignan Cedex, France

Abstract

During the intramolluscan larval development of Schistosoma haematobium (Algerian strain) in Bulinus truncatus, two replication processes of daughter sporocysts occur. Replication by direct sporocystogenesis appears more important than sporocystogenesis post cercariogenesis. These mechanisms assure a periodic renewal of the sporocyst stock in the snail host and seem to be synchronized with the development of cercarial generations. The succession of several generations of cercariae is responsible for the alternation of high and low periods of productivity.

The scheme proposed for the intramolluscan development of S. haematobium is compared with those described for S. mansoni and S. bovis and interpreted in terms of demographic strategies adapted to a better exploitation of the snail host.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1989

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