FIG. 5. Variations in the magnesium content of the blood plasma of rats deficient in magnesium
N.B. 1. These were young growing rats weighing 40-100 gm.
        2. The synthetic ration contained 2 mg. magnesium per 100 gm. (i.e. approximately 0-0024% magnesium in the dry matter).
        3. This ration contained 0-87% calcium or approximately 1-02% in the dry matter.
From TUFTS