Modulation of Intestinal Energy Metabolism and Microbial Profiles by Dietary Starch Characteristics Under EGCG Supplementation in Broiler Chickens

This study evaluated the effects of dietary starch characteristics on intestinal energy metabolism and microbial profiles in Epigallocatechin gallate (EGCG)-supplemented broiler chickens. A total of 300 Arbor Acres male broilers were assigned to five dietary treatments consisting of a corn–soybean basal diet (NC), EGCG supplementation (500 mg/kg) (PC), or diets in which 20% corn was substituted with purified corn (CS), cassava (TS), or pea starch (PS) in the presence of EGCG (500 mg/kg). Growth performance, starch digestion, intestinal energy status, cecal microbiota, and metabolomic profiles were evaluated. The results showed that broilers fed the corn starch-containing diet under EGCG supplementation showed improved average daily gain and feed conversion ratio (p < 0.05). This treatment also increased intestinal ATP and cAMP concentrations while reducing AMP and the AMP/ATP ratio, accompanied by enhanced activities of Na+-K+-ATPase, citrate synthase, and pyruvate dehydrogenase. Cecal microbiota analysis showed that Lactobacillus abundance was increased in the CS group, whereas Barnesiella was enriched in the PS group. Differential metabolites associated with energy metabolism, including lipoic acid, palmitoylcarnitine, and crotonic acid, were significantly changed among treatments. In conclusion, dietary starch characteristics influenced intestinal energy metabolism-related indicators, microbial profiles, and metabolite patterns in broilers receiving EGCG supplementation.