Comparative effects of Chinese green tea (Camellia sinensis) extract and powder as feed supplements for broiler chickens

The comparative effects of green tea extract (GTE) and powder (GTP) on performance of broilers were studied. A total of 405-day-old male Ross 308 broiler chicks were randomly assigned to 9 groups containing 3 replicates of 15 chicks each. The treatments consisted of a control and diets supplemented with 4 levels (10, 20, 30 and 40 g/kg) of GTP and GTE. Feed intake and body weight gain were suppressed (P<.05) by GTP supplementation (P<.05). The best feed conversion ratio was observed on the GTE supplemented group. The highest mortality rate was recorded on the control and the lowest on the GTP groups (P<.05). The best economic index was achieved with GTE supplementation of the diet (P<.05). Relative weights of carcass, breast and drumstick were significantly reduced on GTP compared to GTE (P<.05). GTE up to 40 g/kg diet will maintain growth and feed utilization but inclusion of the powder even as low as 10 g/kg the diet may compromise feed intake, growth performance and carcass traits. Differences in the polyphenol content of the extract (10.2%) and powder (14.9%) may be reasons these performance results. Further studies on green tea source and method of processing are recommended.