Abstract
1. Balance studies were carried out with rats and golden hamsters (Mesocricetus auratus) given diets high and low in calcium (10.8 and 5.1–5.2 g Ca/kg respectively) and high and low in phytate (3.4 and 1.6 g phytate-phosphorus/kg respectively) in a 2 × 2 factorial experiment.2. Values for Ca absorption and phytate availability (relative to the amount ingested) and for urinary excretion of Ca and P were significantly higher in the hamster than in the rat for all four diets.3. Phytate availability was significantly greater on the low-Ca than on the high-Ca diets with both species.4. Ca absorption was greater on the low-phytate than on the high-phytate diets but the differences were significant only for the hamster.5. Absorption of both Ca and P was poorly controlled in the hamster compared to the rat.