Abstract
The study aimed to examine the effects of dietary supplementation with microencapsulated butyric acid (EBA) and yeast culture (YC) in broiler diets. A total of 450 Ross-308 broiler chicks were selected and randomly allocated to five dietary treatments with six replicates (15 birds per replicate) in a complete block design. The experimental diets included the following treatments: (1) Negative control (NC) with basal diet without any additives. (2) Positive control (PC) with basal diet + 0.2 g/kg enramycin. (3) EBA, basal diet + 0.3 g/kg EBA. (4) YC, basal diet + 1 g/kg YC. (5) EBA+YC, basal diet + 0.3 g/kg EBA and 1 g/kg YC. The results indicated a non-significant effect on feed intake (FI) during the experiment periods. However, the EBA+YC treatment exhibited significantly increased body weight gain (BWG), better feed conversion ratio (FCR), and enhanced carcass traits (p < 0.05) compared to other treatments. A significant effect was observed for the immune organ weights and ND titters. Villus height (VH) and the ratio of villus height-to-crypt depth (VH: CD) were noted for EBA+YC across all other treatments. Ileal microbial analysis revealed a significantly lower count of E. coli and Salmonella in the ileal digesta of broiler chickens in the EBA+YC treatment compared to the NC group (p < 0.05). In conclusion, dietary supplementation with any supplement positively influences the broiler's performance, carcass characteristics, gut health, and immune status over the NC group. More pronounced improvements were obtained from the EBA+YC group, indicating that EBA and YC had a synergistic effect on broilers.