RESUMO
It is well documented that choline is known as one of the essential ingredients of phospholipids. Choline acts as a determinative element for appropriate cell membrane functions. On the other hand α-tocopherol (Vit E) is a fat-soluble vitamin. This vitamin acts as a strong antioxidant in the living body's defense system against oxidative stress. Lipid peroxidation in peripartum and early lactating cows is significantly increased while the level of serum Vit E is decreases dramatically. These concomitant physiological changes demonstrate a higher level of oxidative stress subsequently leads to serious health issues in dairy cows. Therefore, the present research was designed to investigate the following items in dairy cattle: 1) evaluation of the possible changes in serum protein fractions, and 2) comparing the oxidative status of orally RPC and vitamin E supplementation in dairy cows in early lactation period. In the current study 30 early lactating primiparous and multiparous Holstein cows (body condition score (BCS)=2.51 ± 0.10) were used beginning five weeks postpartum. All the animals were randomly divided in to three groups (n=10) (number of lactation=2.61). The animals were randomly assigned to receive one of the following treatments. Group 1 served as control group were not received any supplement. The second group was supplemented with 90 g/d of RPC (Reashre Choline, Balchem, USA). The third group was administrated 4400 IU/d vitamin E (Roche, Vitamins Ltd; Switzerland). In the current study, serum protein electrophoresis showed four main fractions as follows: albumin, α-globulin, ß-globulin, and γ-globulin. The recorded data showed that the percentages of albumin and γ-globulin fractions were higher in treated groups compared to the control group. In the animals supplementing with RPC and vitamin E the percentages of serum albumin increased to the value of 37. 70±1.63 and 38.21±1.28 respectively compare to the control group (34.69±1.21), which were significant (P<0.05).