Effect of mineral and vitamin C mix on growth performance and blood corticosterone concentrations in heat-stressed broilers.

Heat stress is a major problem in the poultry industry, especially during summer months and when birds are raised under high-density conditions. Previous studies have reported that vitamin C or electrolyte supplementation could palliate the effects of heat stress in broiler chickens. The present study evaluated the effect of a mineral and vitamin mix (AHS) added to drinking water on the performance of broiler chickens. In total, 1,824 one-day-old birds were randomly allocated to 48 pens. Maximum animal density was 26.5 kg/m2. The control group received no additive; AHS-1 and -2 groups received the AHS mix at a concentration of 1 and 2 kg/1,000 L in drinking water, respectively; and the Vit-C group received vitamin C in drinking water at 200 g/1,000 L. All birds were fed the same diets based on a 3-phase feeding program; feed and water were given on ad libitum basis. To mimic heat stress conditions, temperature in the barn was raised to 35 C from 08:00 to 14:00 h each day. For the overall growing period (0 to 35 D), adding AHS to drinking water increased final BW, ADG, and ADFI linearly (PLinear, 0.05); FCR was decreased linearly with AHS supplementation (PLinear, 0.05). Final BW, ADG, and FCR for the Vit-C group were intermediate between AHS-2 and the control groups (P . 0.10). No significant effect on mortality were found (8.77%; P . 0.10). Relative to control, all the treatments tested reduced (P, 0.05) corticosterone concentration in blood serum. In conclusion, the combined use of supplementary levels of minerals and vitamins could alleviate the effects of heat stress on broilers chickens. [ABSTRACT FROM AUTHOR]