Influence of Green Tea on Performance, Nutrient Utilisation and Cecal Microbiota of Broiler Chickens

The present study was conducted to assess the influence of green tea supplementation on performance, nutrient utilisation and cecal microbiota of broiler chickens. Treatments consisted of a wheat-based basal diet and the basal diet supplemented with one of two types of green tea, namely normal (N-GTE) or selenium-rich (Se-GTE) at an inclusion rate of 1%. Bird performance, nitrogen-corrected apparent metabolizable energy (AMEn), and total tract digestibility of fat and starch were measured on d 7, 21 and 35. In addition, effects on cecal microbiota counts were determined in a cohort study. Green tea supplementation lowered (P<0.05) weight gain and feed intake, but improved feed per gain (P<0.05). Supplementation with N-GTE increased the AMEn on d 7 and 21, and with Se-GTE on d 7 (P<0.05). AMEn increased with age for all treatments. Fat digestibility increased with N-GTE supplementation on d 21 and with Se-GTE supplementation on d 7 and 21 (P <0.05). Starch digestibility increased on d 21 with N-GTE supplementation and on d 7 with Se-GTE supplementation (P<0.05). The abdominal fat pad, as a proportion of carcass weight, decreased in the Se-GTE diet (P<0.05) and numerically in the N-GTE diet. Drip losses were lowered (P<0.05) by both GTE treatments. There was no difference in cooking losses and breastmeat yield between treatments. Dietary inclusion of green tea had a positive effect on the cecal microbiota, with an increased (P<0.05) number of beneficial bacteria (Lactobacillus spp. and Bifidobacterium spp.) and a reduced (P<0.05) number of pathogenic bacteria (Clostridium spp and Bacteroides spp.). Differences were observed between the two green tea types, with Se-GTE being more beneficial than N-GTE in the positive modulation of gut microbiota.