The Excystation,Cultivation and Encystation of Endamoeba colt.

Abstract

Summary

Twenty-six strains of Enda-mæba coli were used for culture experiments, 2 strains in the trophic stage and 24 in the cystic stage. The former did not reproduce in subculture but 15 of the latter excysted and grew abundantly. Four of these are still being cultivated. A modified Locke's egg serum medium plus starch was the only one in which excystation occurred and proved to be the optimum one for continued growth of the organism. The medium was incubated at 37°, had an initial pH of 7.8-8.0 and a final pH of 6.8-7.0. Encystation occurred spontaneously but was never produced at will.