Abstract:
Two experiments were conducted to determine the effect of dietary ascorbic acid supplementation levels on productivity, carcass characteristics and mortality of Venda chickens. The first experiment determined the effect of dietary ascorbic acid supplementation levels on productivity and mortality rate of 175 unsexed Venda chickens between 1 and 6 weeks old. The second experiment determined the effect of dietary ascorbic acid supplementation levels on productivity, carcass characteristics and mortality rate of 140 female Venda chickens between 8 and 13 weeks old. A Completely Randomized Design was used in both experiments. The treatments ranged from 0 to 2000 mg of ascorbic acid per kg DM feed. A quadratic equation was used to determine levels of ascorbic acid supplementation for optimum feed intake, feed conversion ratio, growth rate, live weight and breast meat yield. Feed conversion ratio, growth rate and live weight were optimized at different levels of 1050, 1301 and 1500 mg of ascorbic acid per kg DM feed, respectively, during the starter phase. Similarly, feed conversion ratio, growth rate, live weight and breast meat yield were optimized at different levels of 1000, 1250, 1482 and 769 mg of ascorbic acid per kg DM feed, respectively, during the grower phase. Dietary feed intake in both phases was not optimized within the range of values of ascorbic acid supplementation used in this experiment. The results indicate that at each growth phase, different levels of ascorbic acid supplementation optimized feed conversion ratio, growth rate and live weight of Venda chickens. However, level of ascorbic acid supplementation for optimum breast meat yield was lower than those for feed conversion ratio, growth rate and live weight. These findings have implications on ration formulation for Venda chickens.
