The cultivation of cellulolytic protozoa isolated from the rumen

Conditions are described for the isolation from the rumen and subsequent growth of six species of cellulolytic protozoa: Enoploplastron triloricatum, Eudiplodinium maggii, Diploplastron affine, Epidinium ecaudatum caudatum, Diploidinium monacanthum and Diploidinium pentacanthum. The protozoa were grown in an atmosphere of 95% nitrogen plus 5% carbon dioxide, or pure carbon dioxide, in a potassium phosphate-rich medium containing cysteine, sometimes 10% prepared fresh rumen fluid, and daily additions of powdered dried grass. Population densities of 10 to 6000 protozoa/ml (depending on the species) were obtained in cultures that were diluted with fresh medium twice each week. Extracts of these protozoa digested a [14C]cellulose preparation, liberating soluble 14C-labelled compounds.