Abstract
The study investigates the potential of fenugreek leaf powder (FLP) as a natural feed additive to improve growth performance and intestinal health in yellow-feathered broilers, with a focus on immune function, antioxidant capacity, and gut microbiota regulation. A total of 240, 21-day-old broilers were randomly assigned to four groups, each with six replications and 10 chickens per replication: a control group receiving a basal diet and three groups supplemented with 0.5 %, 1 %, or 2 % FLP for 42 days. Results showed that dietary supplementation with 0.5 % and 1 % FLP significantly improved average daily gain and feed intake (P < 0.05). FLP supplementation enhanced immune function, as reflected by increased serum immunoglobulin levels and immune organ indices (P < 0.05), and improved antioxidant capacity, evidenced by increased antioxidant enzyme activity and reduced lipid peroxidation (P < 0.05). Intestinal morphology was improved, shown by increased duodenal villus height (VH) and better villus height-to-crypt depth (VH/CD) ratios (P < 0.05). FLP also modulated the expression of genes associated with nutrient transport, barrier function, antioxidant defense, and inflammation (P < 0.05). Furthermore, 16S rRNA sequencing indicated that FLP supplementation altered cecal microbial composition. In conclusion, dietary FLP supplementation improves growth performance and intestinal health in broilers, supporting its potential as a natural and cost-effective alternative to antibiotic feed additives in poultry production.