Intestinal pH and Absorption and Deposition of Ca 47 in the Rachitic Chick. ∗

Summary

The effect of pH of the dosing solution on the relative tibia deposition of Ca⁴⁷ absorbed from the duodenum of rachitic and vit. D-treated chicks was examined. Vit. D had its usual enhancing effect on Ca⁴⁷ absorption; however, it was observed that the percent absorbed Ca⁴⁷ deposited in tibia varied with intraduodenal pH and vit. D-status of the chick. At low pH values (1.9, 2.0), there were no differences in the percent of duodenally absorbed Ca⁴⁷ accumulated by tibia in rachitic or vit. D-treated chicks whereas, at high pH values, proportionally less of the absorbed Ca⁴⁷ was deposited in rachitic tibia; pH was without effect on uptake of Ca⁴⁷ by tibia in the vit. D-treated birds.