Effects of Black Tea Powder on Production Performance and Biochemical Parameters of Huainan Spotted-yellow Chicken

Five hundred and twenty-eight Huainan spotted-yellow chickens including 480 female and 48 male(290 days age) were randomly allotted into 4 treatments with four replications and were used in a 50-day performance trail with 4 diets:Control group with zero percent black tea powder in feed,three trail groups with 0.5 percent,1.5 percent and 2.5 percent black tea powder supplemented in control diet,respectively.The results showed that black tea powder scould increase the activity of serum superoxide dismutase(P 0.05 or P 0.01).Suitable concentration of black tea powder in the feed could improve the production and reproductive performances in late laying period,and increase yolk color and concentration of yolk phospholipid.The diets with excessive black tea powder had negative impact on egg shell quality of Huainan spotted-yellow chicken.