title: In vitro studies on intraspecific and interspecific chemical attraction in daughter rediae of Echinostoma trivolvis and E. caproni.
abstract: In vitro pairing and aggregation studies on daughter rediae of Echinostoma trivolvis and E. caproni were done at 22 degrees C in a Petri dish bioassay containing an agar substratum and a Locke's solution overlay. Pairing or aggregation was considered positive when rediae were in contact or within 1 mm of each other. Intraspecific and interspecific pairing or aggregation occurred in the bioassay when rediae were initially placed 5 or 10 mm apart. Movement of a single redia in the bioassay to a dialysis sac containing 1-10 rediae showed that intraspecific and interspecific pairing occurred in the absence of redial tactile stimulation. Movements of single rediae in the bioassay to agar plugs impregnated with redial excretory/secretory (ES) products occurred. The lipophilic fraction of the ES products was significantly more attractive than the hydrophilic fraction. The significance of redial chemical communication is not clear.
authors.affiliation: Department of Biology, Lafayette College, Easton, PA 18042, USA.
authors.forename: A
authors.initials: A
authors.lastname: Reddy
authors.forename: B
authors.initials: B
authors.lastname: Fried
mesh_terms: D000818:Animals; D004449:Echinostoma / Q000378:metabolism*; D000267:Tissue Adhesions