Baicalin Modulates Hepatic Lipid Metabolism and Improves Intestinal Health in White-Feathered Broilers

Liver and intestinal health govern the production performance of broilers. Baicalin (BA) is a flavonoid extracted from the dried roots of Scutellaria baicalensis and possesses a wide range of biological activity. In this study, 66 one-day-old white-feathered broilers were selected and randomly divided into two groups. Broilers in the control group were fed a basal diet, whereas the BA group received the basal diet supplemented with 100 mg/kg BA. The results showed that BA supplementation markedly elevated the antioxidant capacity of the serum and liver (p < 0.05). Meanwhile, the villus height/crypt depth ratio and the activity of intestinal digestive enzymes were significantly higher in the BA group (p < 0.01). Transcriptomics, RT-qPCR, and Western blot assays revealed that BA-mediated effects were associated with the hepatic PPARα signaling pathway and the regulation of lipid metabolism. Furthermore, a combined analysis encompassing intestinal microbiota 16S rRNA sequencing and plasma metabolomics revealed that the BA-induced enrichment of multiple bacterial taxa, such as Lachnospiraceae, may modulate butyrate metabolism and circulating metabolites including isoleucyl-glutamate in broilers. In conclusion, dietary BA supplementation improved the hepatic and intestinal health of white-feathered broilers, reshaped the intestinal microbiota composition, and altered the plasma metabolite profile, with these benefits linked to the PPARα signaling pathway.