Abstract
Gnotobiotic cultures of Entodinium caudatum were prepared from the clones of this protozoon. The organism grew well with any of the bacterial species investigated, irrespective of shape, origin, and gram-staining property. The cultures with Escherichia coli, as well as Streptococcus bovis, were maintained for over 2 months.
The protozoa free from living bacteria were prepared from the gnotobiotic cultures established. These axenic protozoa could be kept alive in the presence of dead bacterial cells for up to 3 weeks, but their growth was extremely slow and the population densities maintained were much lower than those in the cultures with living bacteria.
