Effect of dietary supplementation with phytogenic blend on growth performance, apparent ileal digestibility of nutrients, intestinal morphology, and cecal microflora of broiler chickens.

The effects of dietary supplementation with phytogenic blend (PB) of Aerva lanata, Piper betle, Cynodon dactylon, and Piper nigrum on growth performance, ileal nutrient digestibility, intestinal morphology, and cecal microflora were determined in a 42-day broiler feeding trial. A total of 192 broilers were assigned to 4 dietary treatments (6 replicates and 8 birds/replicate): basal diet, basal diet supplemented with antibiotic (chlortetracycline), 1% and 2% PB, respectively. The body weight gain (BWG) of starter chicks increased linearly (P = 0.023) as dietary supplementation levels of PB increased. At grower phase, broilers fed diet supplemented with 1% PB had similar BWG with the antibiotic group, but other treatments had reduced (P = 0.0001) BWG. Dietary supplementation with 1% PB resulted in the highest (P < 0.0001) BWG during the study. Feed intake was not affected by the treatments during the starter, finisher, and overall rearing periods. Broilers fed diet supplemented with 1% PB had the best (P < 0.0001) feed conversion ratio during the study. Overall, broilers fed only basal diet had the highest (P = 0.0450) mortality. Ileal organic matter (OM) digestibility increased linearly (P = 0.044) with broilers fed diet supplemented with PB, but reduced with antibiotic group. Dietary supplementation with 1% PB had the highest (P = 0.0402) ileal digestibility of tryptophan. In the duodenum, broilers fed diet supplemented with PB had longer (P = 0.0006) villi heights than the birds fed only basal diet, but similar with antibiotic group. Broilers fed diet supplemented with PB had longer (P = 0.0064) villi height in the jejunum than the antibiotic group. Bifidobacterium concentration of the cecum content showed a slight increase (P = 0.053) with increasing supplementation levels of PB. In conclusion, the current study shows that dietary supplementation with PB improves growth performance, intestinal morphology, and apparent ileal digestibility of OM and tryptophan in a dose-dependent manner with the best response at 1% inclusion level.