Effects of Feeding Rumen-Protected Choline and Vitamin E on Serum Protein Fractions, Total Thiol Molecules and Total Antioxidant Capacity in Early Lactating Dairy Cows

Twenty four primiparous and multiparous Holstein cows on early lactation, beginning five weeks postpartum, were used for four weeks to investigate the effects of supplementation of rumen-protected choline (RPC) or vitamin E on blood serum protein fractions, plasma total thiol molecules (TTM), and plasma total antioxidant capacity (TAC). Cows were randomly assigned to one of the following treatments: I - no supplement (control), II - 90 g/d of RPC, and III - 4400 IU/d of vitamin E. Serum protein electrophoresis of samples exhibited four main fractions in the blood serum of the cows including: albumin, α, β, and γ. The electrophoresis was carried out by capillary zone electrophoresis (CZE). In this study, feeding RPC or vitamin E affected the blood serum albumin fraction as well as blood plasma TTM (P<0.05) but the treatments did not affect the different fractions of globulin as well as plasma TAC (P>0.05). The results showed that the increases in serum albumin fractions and TTM which observed in this study, pointed towards a beneficial role of RPC and vitamin E in early lactating dairy cows.