Comparative effects of Mannan oligosaccharide, synbiotic, and their combination on growth performance and intestinal health in broiler chickens

This study evaluated the effects of mannan oligosaccharide (MOS), synbiotic, and their combination (M + S) on growth performance, gut morphology, microbial population, and immune response of broiler chickens. A total of 500 Cobb 500 chicks were allocated into five dietary treatments: control, antibiotic, MOS, synbiotic, and M + S, with five replicates of 20 birds each, in a completely randomized design for 42 days. Results showed that MOS, synbiotic, and M + S improved daily body weight gain during the during 1–21 days of age and over the entire experimental period (1–42 days) compared with the control ( P < 0.05). No significant differences were observed in feed intake or feed conversion ratio. Jejunal morphology analysis revealed longer villi in the antibiotic and synbiotic groups, while villus thickness was reduced in M + S and antibiotic groups ( P < 0.05). The M + S treatment significantly reduced E. coli counts and pH in both ileum and cecum ( P < 0.05), while enhancing total bacteria and Lactobacillus populations. Although numerical increases in Newcastle disease virus antibody titers were observed, the differences were not statistically significant. In conclusion, MOS and synbiotic, especially in combination, improved broiler performance and modulated gut microbial balance, suggesting their potential as effective alternatives to antibiotics in poultry production.