Effect of Taiwanese Green Propolis Ethanolic Extract on Growth Performance, Serum Biochemical Parameters, Intestinal Inflammation-Associated Gene Expression, and Fecal Microbiota in Pullets

ABSTRACT This study examined the effects of the supplementation of drinking water with Taiwanese green propolis ethanolic extract (TGPE) on the growth performance, serum biochemical parameters, intestinal inflammation-associated gene expression, and fecal microbiota in pullets. One-day-old pullets were divided into (1) a control group (without TGPE supplementation) (C), (2) a low-dose group (300 µg/mL TGPE) (L), and (3) a high-dose group (600 µg/mL TGPE) (H). Chicks were provided ad libitum access to feed and water for 12 weeks. The results revealed that there was no significant difference in growth performance and blood biochemical parameters among groups. Supplementation with 600 µg/mL TGPE reduced inflammation-associated gene expression in the duodenum and ileum. TGPE supplementation (300 and 600 µg/mL) reduced α-diversity (richness and evenness) in the feces of laying hen chicks at 12 weeks of age. β-diversity confirmed that bacterial structure were well-separated at 4, 8, and 12 weeks of age. TGPE supplementation (300 and 600 µg/mL) increased the abundance of the genus Lactobacillus and reduced the abundance of the genus Escherichia-Shigella. The abundance of the genus Escherichia-Shigella was positively correlated with inflammation-associated gene expressions, whereas the abundance of the genus Lactobacillus was inversely correlated with inflammation-associated gene expression in pullets at 12 weeks of age. In conclusion, supplementing drinking water with TGPE can reduce intestinal inflammation-associated gene expression and modulate fecal microbiota in pullets. TGPE at the optimal concentration of 600 µg/mL in drinking water may have anti-inflammatory effects and modulates gut microbiota in pullets.