Effect of Vitamin E and Zinc supplementation on the growth performance, immunity, serum biochemistry and antioxidant profile of broiler chicken under heat stress

Raza, M., Deo, C. and Siddiqui, R. 2024. Effect of Vitamin E and Zinc supplementation on the growth performance, immunity, serum biochemistry and antioxidant profile of broiler chicken under heat stress. Indian Journal of Poultry Science, 59(3): 247–255. A six-week feeding trial was carried out to evaluate the effects of dietary vitamin E and zinc on growth performance, immune response, and serum biochemical profile in broiler chickens. A total of 360 mixed-sex day-old chicks were randomly assigned to nine dietary treatments in a 3×3 factorial design, with three levels of vitamin E (50, 100, and 150 IU/kg diet) and three levels of zinc (40, 80, and 120 mg Zn/kg diet). Each treatment had five replicates of eight birds each. Birds were reared under ad libitum feeding and watering conditions, and body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR) were recorded across starter (0-3 weeks) and finisher (4-6 weeks) phases. Results indicated that birds supplemented with 100 IU/kg vitamin E and 80 mg Zn/kg diet exhibited significantly higher BWG and better feed efficiency. FI was higher at 50 IU/kg vitamin E with 40 mg Zn/kg diet, whereas FCR improved with 150 IU/kg vitamin E and 120 mg Zn/kg diet. Significantly (p=0.05) higher serum total protein was observed at 150 IU/kg vitamin E with 40 mg Zn/kg diet compared to 150 IU/kg vitamin E with 120 mg Zn/kg diet and 50 IU/kg vitamin E with 40 mg Zn/kg diet. Serum triglycerides was significantly higher at 50 IU/kg vitamin E than those recorded at other levels. Immune responses were significantly enhanced at 100 IU/kg vitamin E with 80 mg Zn/kg diet. Spleen weight was significantly affected by dietary treatments, but thymus and bursa weights remained unaffected. The study concluded that supplementation of 100 IU/kg vitamin E with 80 mg Zn/kg diet is optimal for improving growth performance, immune response, and feed efficiency in broiler chickens under heat-stressed conditions.