Effect of zinc supplementation on haematology and serum biochemical constituents in Murrah buffalo calves

Eighteen buffalo calves (125±2.5 kg) were randomly allotted to 3 groups in a completely randomized design. The dietary treatments were viz., Basal diet (BD; 29.72 ppm Zn from feed ingredients), BD supplemented with 80 and 140 ppm Zn as ZnSO₄.7H₂O (22% Zn). The nutritional requirements were met by feeding sorghum stover based complete diets comprising of mainly sorghum stover, maize grain, soya bean meal and red gram chunni for a period of 120 days. Results showed that Zn supplementation at either 80 or 140 ppm had no influence on haematological constituents (haemoglobin, total erythrocyte and leucocytes count, packed cell volume, MCV, lymphocytes, monocytes and granulocytes) and biochemical constituents (total protein, albumin, cholesterol, glucose and albumin: globulin ratio) analyzed at 90 d of trial. Irrespective of dose, alkaline phosphatase activity and globulin concentration in serum increased (P<0.05) with Zn supplementation and no difference was observed between two doses of Zn supplementation. The Zn supplementation at higher concentration (140 ppm) had no adverse affect on concentrations of copper, manganese and iron in the serum at 60, 90 and 120 d of blood collection. An increase in serum Zn concentration was observed in 80 and 140 ppm Zn supplemented calves at 120 d of experiment. The study indicated that Zn supplementation at either 80 or 140 ppm in diets of buffalo calves improved the serum globulin concentration, a component of immune system and Zn supplementation up to 140 ppm (total dietary concentration of 169.72 mg/kg) had no adverse effect on serum trace mineral concentration, haematological and biochemical constituents.