This study was carried out to evaluate the effects of herbal mixture on the growth performance, intestinal microbial population, and immune responses of broiler chickens. In all, 600 day-old as-hatched Ross 308 broiler chickens were assigned in a completely randomized design with four treatments, five replicates, and 30 birds in each replicate. The four treatments were: the control group (not treated) and, the second group received 1 mL L-1 herbal solutions (Bioherbal®), and two other groups were received 16.6, and 33.3 mL L-1 commercial herbal solutions (Orex®), respectively. Results showed that while water supplementation of the herbal mixture had no significant effect on feed intake (FI), body weight (BW), and feed conversion ratio (FCR) of broiler chickens (p > 0.05), the productive efficiency index (PEI) improved by dietary inclusion of herbal blend at 33.3 mL L-1 (p < 0.05). Furthermore, the lactobacilli population increased and E. coli population was reduced by both herbal mixture addition (p < 0.05). The application of both Herbal growth promoters (Orex® and Bioherbal®) boosted cellular and humoral immunity and decreased the heterophil-to-lymphocyte ratio (p < 0.05). The present study indicated the positive effect of Orex® addition to water at both concentrations (16.6 or 33.3 mL L-1) on livability, PEI, ileal microbial populations, and immune system function.
Alizadeh‐Ghamsari et al. (Fri,) studied this question.