Distribution of elements between solid and supernatant fractions of digesta in sheep given six diets.

Abstract Three fresh and three dried diets comprising grasses and legumes were fed to six sheep, housed in metabolism crates, to determine the distribution of mineral elements between solids and supernatant fractions of rumen and abomasal digesta. Apparent absorption of elements from the rumen and intestine were also measured, together with dry matter (DM) digestibility. The feeds offered were fresh perennial ryegrass, fresh red clover, fresh lucerne, chaffed lucerne hay, chaffed meadow hay, and lucerne pellets. The feeds provided a 2-fold range in concentration of macro- and micro-elements in their DM (except for zinc (Zn)), with DM digestibilities from 54 to 78%. In rumen contents (pH 6.3–6.5) over 85% of calcium (Ca), manganese (Mn), copper (Cu), and zinc (Zn), and over 70% of magnesium (Mg), phosphorus (P), sulphur (S), and iron (Fe) were associated with the solid fraction (except for Mg and P with ryegrass). Potassium (K) and sodium (Na) predominated in the supernatant. In the abomasum (pH 2.4–2.9) l...