Broiler Chickens and Xuefeng Black-bone Chickens were used for examining the effects of Eucommia ulmoedes oliver leaves as a feed additive on their performance. Mealed Eucommia ulmoedes oliver leaves were added to a basal diet at 0% (control),0.5%,1.0%,1.5% and 2.0%. At the end of the 60-day and 90-day feeding trial, daily weight gains, feed efficiency (feed /gains), carcass characters (breast and thigh muscle ratios and abdominal fat ratios) and blood parameters were measured. The results indicated that fe...