Development of Multi-Bioactive Driven Composite Plant Extracts and Functional Study in Mice and Piglets

This study aimed to develop a multi-bioactive composite plant extract as an alternative to dietary antibiotics for application in animal production. Five plant materials were initially selected from 23 candidate plants via in vitro antibacterial, antioxidant, and anti-inflammatory screening, and formulated into three candidate extracts (C1, C2, C3) by orthogonal design, with respective dominant activities and moderate the other activities. Three feeding trials in mice demonstrated that administration of 1000 mg/kg C1 or C2 caused no adverse effects on hematological parameters or organ indexes. Supplementation with 250 mg/kg C1 or 125 mg/kg C2 significantly increased body weight gain and feed intake, reduced the feed-to-gain ratio, and modulated gut microbiota composition. In LPS-challenged mice, C1 and C2 restored jejunal villus height and crypt depth, downregulated the gene expression of TLR4, TNF-α, NF-κB, and IL-1β, and increased hepatic T-AOC activity while decreasing MDA content. Furthermore, a feeding trial in piglets demonstrated that dietary supplementation with 200 mg/kg C2 achieved growth performance comparable to that of conventional antibiotic supplementation, highlighting its potential as a substitute for feed antibiotics. In conclusion, this study has developed a new multi-bioactive composite plant extract that may serve as a promising alternative to feed antibiotics.