# Effects of a Compound Probiotic on Production Performance, Intestinal Health, Immune Function, and Gut Microbiota in Broiler Chickens

## TL;DR

A multi-strain probiotic improves growth, meat quality, immunity, and gut health in broiler chickens.

## Contribution

This study demonstrates the combined benefits of a five-strain probiotic on multiple aspects of broiler health and performance.

## Key findings

- Probiotic supplementation increased growth performance and feed efficiency in broilers.
- The probiotic improved meat quality, including tenderness and water-holding capacity.
- Probiotic-fed broilers showed enhanced immune responses and gut microbiota composition.

## Abstract

Maintaining good intestinal health is essential for disease resistance and overall health in broiler chickens. Probiotics are commonly used in poultry production, but the combined effects of specific multi-strain probiotics on growth, meat quality, immunity, and gut health are not fully understood. In this study, we evaluated a compound probiotic containing five beneficial microorganisms and its effects on broiler chickens during a 42-day feeding trial. Broilers receiving the probiotic supplement showed improved growth performance and feed efficiency, as well as better meat quality, including increased tenderness and water-holding capacity. Probiotic supplementation also enhanced immune responses and antioxidant capacity while reducing inflammatory markers in the blood. In addition, the probiotic improved intestinal structure, strengthened the gut barrier, and favorably altered the composition of intestinal microbiota. Overall, our findings indicate that dietary supplementation with this multi-strain probiotic can effectively support intestinal health, immune function, and overall performance in broiler chickens, suggesting its potential as a practical nutritional strategy to promote poultry health and productivity.

Maintaining intestinal health is fundamental to immune competence and disease resistance in broiler chickens; however, effective nutritional strategies that enhance gut barrier integrity and systemic health remain under investigation. This study evaluated the effects of a multi-strain probiotic composed of Lactobacillus buchneri, Lactobacillus casei, Lactobacillus fermentum, Lactiplantibacillus plantarum, and Bacillus subtilis on growth performance, meat quality, immune response, antioxidant capacity, and intestinal health in broilers. The research included 144 Ross 308 broilers aged one day, distributed randomly into two diet groups, each containing 6 replicates of 12 birds. During the 42 d trial, the control group (CON) was fed a basal diet composed of corn and soybean meal, with the compound probiotics (CP) diet additionally containing 0.3% compound microbial preparation. Growth performance, meat quality, serum immune and antioxidant indices, intestinal morphology, intestinal barrier-related genes and cecal microbiota were analyzed. Compared with the CON, CP supplementation significantly increased average daily gain, reduced feed conversion ratio, and improved eviscerated and breast muscle yields (p < 0.05). Meat quality was enhanced, as indicated by higher pH45min, increased redness (a*), and reduced shear force and drip loss in breast muscle (p < 0.05). In addition, CP broilers exhibited improved amino acid and fatty acid profiles in breast muscle (p < 0.05). Serum analysis revealed elevated immunoglobulin G and interleukin-10 levels, reduced pro-inflammatory cytokines, and enhanced antioxidant capacity in the CP group (p < 0.05). Probiotic supplementation significantly improved intestinal morphology and upregulated barrier-related genes such as mucin-1 (MUC-1), claudin-1(CLDN-1), zonula occludens-1 (ZO-1), and occludin (OCLN) (p < 0.05). Moreover, cecal microbiota analysis demonstrated increased abundance of Bacteroidota and enrichment of beneficial genera, including Megamonas, Ruminococcus, and Prevotella (p < 0.05). Overall, dietary supplementation with 0.3% compound probiotics effectively enhanced growth performance, immune function, antioxidant capacity, and intestinal health in broilers.