Effect of Dietary Ascorbic Acid Supplementation on Egg Production, Egg Quality and Hatchability of Indigenous Venda Chicken Hens

摘要

An experiment was conducted to evaluate the effect of ascorbic acid supplementation on egg production, egg quality and hatchability of Venda hens. A total of 75 indigenous Venda chickens hens were randomly assigned to five ascorbic acid supplementation levels with three replications, each having five birds. The study was a completely randomized design. The experimental diets were isocaloric and isonitrogenous but with different ascorbic acid supplementation levels ranging between 0, 200, 500, 1000 and 1500 mg of ascorbic acid per kg DM feed. Level of dietary ascorbic acid supplementation had effect (p<0.05) on Venda hens egg weight, egg albumen weight, egg yolk weight, egg shell weight and hatchability values. Venda hens supplemented with 200 and 500 mg of ascorbic acid per kg DM feed produced heavier (p<0.05) eggs than those from hens supplemented with 1000 and 1500 mg of ascorbic acid per kg DM feed as well as those from the unsupplemented birds. Venda hens supplemented with 200 mg of ascorbic acid per kg DM feed produced eggs with higher (p<0.05) hatchability values than eggs from hens supplemented with 1500 mg of ascorbic acid per kg DM feed and the unsupplemented birds. Additionally, optimum ascorbic acid supplementation level of 700 mg kg~(-1) DM feed supported optimum egg production while a higher ratio of 750 mg kg~(-1) DM feed supported optimum hatchability. It is concluded that ascorbic acid supplementation to the diets of indigenous Venda chicken hens is desirable, mainly because of its positive effect on egg weight and hatchability.