The effects of dietary oxyberberine supplementation on the growth performance, carcass traits, blood biochemical parameters and intestinal health in broilers.

Oxyberberine (OBB), a novel intestinal metabolite of berberine (BBR), has demonstrated anti-tumor, anti-inflammatory and antioxidant activities superior to those of BBR. Nevertheless, current studies on OBB have focused primarily on rodents, and its potential as a livestock feed additive for nutritional regulation remains largely unexplored. The present study aimed to elucidate the effect of dietary OBB on growth performance, biochemical parameters and intestinal health of broilers. A total of 300 1-d female broilers (Shengze 901+) were randomized into five treatment groups (6 pens/treatment and 10 birds/pen): basal diet group as control (Control), basal diet + 50 mg/kg BBR (BBR 50), basal diet + 25 mg/kg OBB (OBB 25), basal diet + 50 mg/kg OBB (OBB 50), basal diet + 75 mg/kg OBB (OBB 75). The feeding trial lasted for 6 weeks, dividing into an early stage (1-21 d) and a late stage (21-42 d). These findings demonstrated that supplementing with 25 mg/kg OBB dramatically improved the growth performance of broilers during the later growth phase (P < 0.05), and also apparently increased semi-eviscerated, eviscerated and breast muscle weights (P < 0.05). OBB supplementation markedly increased the activities of SOD, CAT, T-AOC and GSH-Px (P < 0.05), while also significantly decreasing serum DAO and enhancing immune function by boosting IgA, IgM, and IgG concentrations (P < 0.05). OBB supplementation markedly (P < 0.05) lowered serum UN, TC, and TG levels, as well as noticeably upregulated the expressions of tight junction proteins and augmented the number of goblet cells (P < 0.05). 16S rRNA sequencing revealed that significant enrichment of Prevotellaceae, Desulfovibrio and Bacillales in the OBB 25 group. Taken together, supplementation with OBB, especially 25 mg/kg, could improve growth performance and slaughter performance, which may be related to improving antioxidation capacity, immune function and intestinal barrier function.