Abstract
The increase in the R-fraction (total base determined by resin method, mEq/l-chlorine mEq/l) in the plasma of hen during egg-laying period was reported in the previous paper. Another type of investig-ation of this phenomenon was performed using the serum of estrogenized rooster. The amounts of diff-usible and non-diffusible calcium were determined by an ultrafiltration technique. The results confirm that the lipoprotein in the serum of estrogenized rooster is responsible for the increases in the R-fraction and in the protein-bound calcium.
