Effect of ammonia treatment of straw on rumen environmental conditions affecting fibre degradation

Abstract

The increase in rumen digestion of cereal straw by its treatment with anhydrous ammonia has been commonly explained by a chemical action on plant cell wall structure, increasing its solubility and potential degradability, and by an enhancement of microbial access to degradable cell wall. However, although some authors (Kolankaya et al., 1985; Balcells et al., 1993) have also reported an increase in rumen microbial synthesis and activity by treating straw with ammonia, Fondevila et al. (1993) did not observed a higher rumen degradation in sheep given ammonia-treated straw compared with untreated straw. This work was conducted to study straw cell wall degradation and the possible differences on rumen fermentation characteristics induced by ammoniation of dietary straw.