A short-term study of calcium and phosphorus absorption in sheep fed on diets high and low in calcium and phosphorus

Abstract

Compartmental modelling techniques were used to measure the absorption of calcium and phosphorus in young sheep which had been fed ad libitum for 6 months on one of four diets containing 1.35 or 8.2 g calcium and 0.72 or 4.5 g phosphorus per kg dry matter. In most of the compartmental models, absorption could be represented by a primary and secondary compartment. The percentage of 45Ca absorbed increased as calcium intake decreased so that the amount of calcium absorbed was not greatly affected by changes in the dietary intake or abomasal contents of calcium. Also, there were no differences due to treatment in the amount of calcium absorbed by primary or secondary absorption. The percentage ..