The biochemistry of rumen protozoa. 1. Carbohydrate fermentation by Dasytricha and Isotricha

Abstract

Suspensions of Dasytricha ruminantium and of mixed Isotricha intestinalis and Isotricha prostoma have been prepared from the rumen liquor of specially treated sheep, and used in manometric experiments. The D. ruminantium suspensions, but not the isotrichs, were able to ferment galactose, maltose and cellobiose. Some naturally occurring (3-glucosides were more readily fermented by D. ruminantium than by the isotrichs. The products of galactose fermentation by D. ruminantium were the same as those formed from glucose by the same species. Only the isotrichs could ferment rice-starch grains; neither genus could utilize starch grains from rumen holotrichs. Previous observations on the rumen holotrichs, mostly made on mixtures of Dasytricha and Isotricha, are discussed in the light of these results.