Effects of Astragalus membranaceus on laying performance and antioxidant status of laying hens

SUMMARY Interest in the use of natural feed additives in the animal and poultry industries is growing. In the present study, we assessed the effects of dietary supplementation of Astragalus membranaceus root powder (AMP) on the laying performance and serum and egg yolk antioxidant status of laying hens. Four groups (135 each) of laying hens fed a corn- and soybean meal-based diet were supplemented with 0, 5, 10, or 15 g/kg of diet of AMP for 10 wk, and their laying performance and serum and egg yolk antioxidant status were measured. Supplementation of AMP did not affect ADFI or average egg weight but did linearly increase egg mass of the laying hens. Antioxidant status of the serum and egg yolk was improved, as judged by an increase in antioxidant enzymatic activities and a decrease in concentrations of oxidized products, with supplementation of AMP in a dose-dependent manner. In conclusion, supplementing a cornand soybean meal-based laying hen diet with AMP at levels of 5 to 10 g/kg of diet had the potential to improve the antioxidant status of laying hens and improve laying performance.