Influence of Organic Zinc (Zn Proteinate) Supplementation on Antioxidant Status, Blood Biochemistry and Immunity in Buffalo Heifers

Abstract

Eighteen buffalo heifers (261.1±11.6 kg) were randomly allotted to 3 dietary groups in a completely randomized design to determine the effect of organic and inorganic Zn combinations on antioxidant status, blood biochemistry and immune response. The concentrate mixture was supplemented with 80 ppm Zn, supplied from 100% ZnSO4 (100 I-0 O, control), 75% Zn from ZnSO4 and 25% from Zn Proteinate (ZnProt, 75 I-25 O) and 50% from ZnSO4 and 50% as ZnProt (50 I-50 O) up to 90 days of experiment. The humoral immune response was assessed against Brucella abortus S19 and chicken RBC antigens by administering suitable doses on 60th d with a booster dose after 15 days and antibody titres against these antigens were measured by standard tube agglutination test and direct haemagglutination test, respectively in serum collected at 8, 15, 22 and 29 d post sensitization. At the end of experiment, cell mediated immune response was determined by in vivo delayed type hyper sensitivity reaction against phytohaemagglutinin-P. Lipid peroxidation and glutathione peroxidase activity was comparable among the three dietary groups while RBC-catalase activity was higher in organic Zn combination groups compared to the 100% inorganic Zn supplemental group. The levels of alkaline phosphatase activity, serum glucose, cholesterol, serum total protein, albumin, globulin and albumin: globulin ratio and serum Zn in heifers of groups 100 I-0 O, 75 I-25 O and 50 I-50 O were comparable. The humoral immune response against both the antigens was not affected with replacement of inorganic with organic Zn source. The cell mediated immune response was higher (P<0.05) with inclusion of ZnProt replacing 25 or 50% of ZnSO4. The results indicated that supplementing 80 ppm Zn in diets as combinations of inorganic and organic Zn in ratio of 75: 25 or 50: 50 had no effect on biochemical constituents and humoral immune response in buffalo heifers. The cell mediated immune response and RBC-catalase activity improved with replacing inorganic Zn with organic Zn by 25%.