Criteria for Judging a True Rumen Organism and a Description of Five Rumen Bacteria

In recent years several investigators have isolated bacteria in pure culture from the rumen and have studied these bacteria. Kohler (8), Johnson et al. Pochon (9) isolated an anaerobic, spore-forming, cellulose-digesting rod from undiluted rumen contents, while Sijepsteijn (11) also has isolated several cellulose-digesting bacteria from raw rumen contents, but only a few were obtained in pure culture. Hungate (4, 5) isolated several anaerobic cellulose-digesting bacteria from diluted rumen contents, and analyses were carried out on the end-products formed when these organisms break down cellulose. Johns (6) used the Warburg technic to study the mechanism of propionie acid formation brought about by an anaerobic micrococcus obtained from the rumen of sheep.