Abstract
Necrotic enteritis (NE) caused by coccidia and Clostridium perfringens (CCP) infection poses significant economic losses in poultry production. The present study aimed to identify the potential beneficial effects of Lactobacillus reuteri (LR) postbiotics on broilers under necrotic enteritis challenge. A total of 180 Arbor Acres+ broilers were randomly assigned to three groups: control group (CTR, fed basal diet), CCP group (challenged with CCP) and LR + CCP group (100 mg/kg LR with CCP infection). The formal animal experiment lasted for 28 days. The results showed that LR + CCP group exhibited higher body weight on days 19 and 28 compared with the CCP group, along with increased average daily feed intake and average daily gain during days 1-18, 19-28 and 1-28 (P < 0.05). The LR supplementation significantly reduced plasma diamine oxidase and lysozyme levels, increased jejunal villus height and ileal Claudin-1 and Mucin2 expression of NE-challenged broilers (P < 0.05). It down-regulated ileal IL-1β, IFN-γ, NOD1 and TGF-β expression and up-regulated jejunal MHC-II and ileal Leap2 expression of challenged broilers (P < 0.05). Furthermore, LR supplementation decreased ileal Firmicutes and Proteobacteria and increased Bacteroidota abundance (P < 0.05). In summary, dietary LR improved intestinal morphology, mitigated intestinal inflammation, and modulated ileal microbiota, contributing to the improvement of intestinal health and growth performance of NE-challenged broilers.