Utilization of Lolium multiflorum by sheep 2. The effect of drying the herbage on soluble nitrogen content and partial digestion

Abstract

The amount of soluble N and the effective degradation of fresh and dry herbage of Lolium multiflorum cv. Midmar (ryegrass) was determined by the nylon bag technique. In another experiment the digestion and disappearance of organic matter (OM) and nitrogen (N) were measured on fresh and dry ryegrass herbage fed to sheep either ad lib or at ad lib‐20%. The amount of soluble N was reduced by drying at 60°C but the effective degradation remained unaltered. The disappearance of OM and N components in the digestive tract was not significantly influenced by treatment but the effect of level of intake was significant. There was, however, no significant treatment × feeding level interaction. The soluble N content of ryegrass did not affect non‐ammonia N absorption in the small intestine significantly. It was concluded that amino acid absorption from the small intestine will not be limiting at dry matter contents of Midmar ryegrass of 18–20%.