Effects of Supplemental Ascorbic Acid on the Performance and Immunity of Commercial Broilers

Abstract

An experiment was conducted to evaluate the efficacy of supplemental ascorbic acid on the performance of broiler chickens. Three hundred thirty Ross chicks were divided into 5 groups of 66 each, comprising 3 replicates. They were fed 0, 10, 50, 100, and 200 ppm of supplemental ascorbic acid, respectively, for a period of 6 wk. The performance data revealed significantly higher weight gains in the supplemental groups at higher levels as compared with control. The nutrients’ digestibility during starter and finisher phases was significantly higher at higher levels of supplementation. The carcass traits were significantly better in supplemented groups than the control; however, abdominal fat percentage was not affected. The bone resistance was improved at higher levels of ascorbic acid supplementation, since the bone mineral content (Ca and P) was higher in these groups. As the levels of supplementation increased, the ascorbic acid content in plasma and liver also increased linearly. The lymphocyte subpopulation measured showed higher CD4 and T-cell receptor-II (TCR-II) cells in the 100-ppm supplemented group as compared with its counterparts. The infectious bursal disease (IBD) and Newcastle disease (ND) titers measured postvaccination showed significantly higher IBD titers in the 200-ppm group. It can be concluded from the above study that supplementation of ascorbic acid at 200 ppm is beneficial for improving the performance and immunity and for exploiting the full genetic potential of the commercial broilers.