Extent of Solubilization of -Cellulose and Hemicellulose of Low-protein Teff Hay by Pure Cultures of Cellulolytic Rumen Bacteria

Abstract

SUMMARY Ten isolates belonging to the genus Butyri vibrio and two each of Rumino-coccusalbus, R. flavefaciens and an unidentified Clostridium sp. were isolated from high dilutions of rumen fluid from sheep conditioned to low-protein teff hay. The butyrivibrios solubilized between io and 37 % of the α-cellulose of the hay (average 21 %). The two isolates of Ritminococcus albus degraded 43 and 56 % of the α-cellulose and the two of R. flavefaciens 39 and 66 %, while the two Clostridium cultures achieved only 10 % degradation. Hemicellulose degradation by the Butyrivibrio isolates was between 25 and 67 % (mean 48 %) and that by the four Ruminococcus cultures between 47 and 65 %. One of the Clostridium cultures solubilized 21 % and the other 51 % of die hemicellulose. The butyrivibrios appear capable of contributing a greater share towards cellulose digestion in ruminants on low-protein hay than has been inferred from qualitative in vitro tests for cellulolysis, using refined cellulose preparations; they are probably less active than the ruminococci.