Influence of Dietary Zinc and its Sources on Growth, Body Zinc Deposition and Immunity in Broiler Chicks

Effect of Zn supplementation from organic and inorganic sources was evaluated on the performance of broiler chicks fed on maize-soybean meal diet. A total 150 day-old-unsexed broiler chicks were randomly assigned to 3 treatments for 35 days. The basal diet (23.19 to 26.46 ppm Zn) was supplemented with 15 ppm Zn either as zinc sulfate or zinc proteinate. Live weight was significantly (P≤0.01) increased following Zn supplementation, irrespective of its source. However, feed intake and FCR were not affected by Zn supplementation. The level and sources of dietary Zn did not influence tibia ash (%) and muscle Zn content. Tibial Zn concentration was increased (P<0.01) by dietary Zn content and the response was greater in birds supplemented with zinc proteinate. Concentration of Zn in liver was significantly affected (P<0.05) by supplemental Zn, but not affected by the source. Antibody titer against ND virus vaccine at 35 days was increased (P<0.01) with Zn supplementation, and the increment was higher in Zn propionate supplemented birds than those supplemented with zinc sulfate. It was concluded that supplementation of maize-soybean meal diet with Zn at 15 ppm either from zinc sulfate or zinc proteinate improved broiler performance, but a better immune response occurred when Zn proteinate was added to the dietversus Zn sulfate.