Effects of inulin on rumen metabolism in vitro

Abstract

The objective of this study was to investigate the effects of inulin [as topinambur (Helianthus tuberosus L.) powder] on in vitro rumen fermentation of diets containing hay and pelleted concentrate for sheep (approximately 60:40%) in artificial rumen (the RUSITEC system). The RUSITEC system consisted of six fermentation vessels. Topinambur powder was added at levels of 0.2, 0.4, 0.6, 0.8 and 1.0 g/day into the five fermentation vessels while the last one served as a control (without having any topinambur powder). The results showed that the addition of topinambur powder up to 1.0 g/day reduced NH3-N concentration significantly (p<0.05). However, the other basal parameters of rumen fermentation (pH, short-chain fatty acid production and organic matter digestibility) examined in this study were not significantly affected by the addition of topinambur powder. These results indicated that inulin has the potential to improve ruminal nitrogen utilization.