Co-Authors:
Ben-Ghedalia, D., Institute of Animal Science, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
Yosef, E., Institute of Animal Science, Agricultural Research Organization, The Volcani Center, Bet Dagan, 50250, Israel
Abstract:
The participation of neutral detergent (ND)-soluble and cell wall (CW) monosaccharide residues in the fermentation of silages made of lucerne + wheat straw was studied in 2-l laboratory glass silos. The treatments consisted of: (a) lucerne wilted to 30% dry matter (DM) prior to ensilage (WL); (b) fresh lucerne + untreated wheat straw at a ratio of 60 40 on a DM basis (L + WS); (c) fresh lucerne + SO2-treated wheat straw at the same ratio (L + 40%TWS); (d) fresh lucerne + SO2-treated wheat straw at a ratio of 50 50 on a DM basis (L + 50%TWS). Silos were opened after 90 days of fermentation and silages were analyzed. ND-soluble glucose was extensively or completely fermented in the four silages, whereas the ND-soluble uronic acid (pectin) was hardly affected after 90 days of fermentation. The highest recoveries of ND-soluble sugar residues were in the L + 50%TWS silage. CW glucose and xylose did not participate in silage fermentation, but the minor CW sugars (arabinose, galactose and mannose) were slightly degraded in the L + WS and L + 50%TWS silages. The results indicate that the level of inclusion of SO2-treated wheat straw will determine whether the source material will be preserved as a result of direct acidification of the HSO3- residues present in the TWS, or as a consequence of normal fermentation of the CW-derived soluble sugars contributed by the TWS. © 1989.