Changes in Specific Blood Serum Protein Levels Associated with Parturition in the Bovine

Abstract

Starting about 14 weeks before parturition, the level of serum proteins in the blood of the bovine started increasing to reach a maximum about 4 weeks before parturition and then started decreasing to reach a minimum at parturition. The drop at parturition was caused by a loss of immune [beta]2- and [gamma]1-globulins and some [beta]-globulins from the blood; the level of serum albumin and the [beta]1- and [gamma]2-globulins did not change appreciably. The drop corresponded with the time the colostrum was being formed in the mammary gland.