Influence of purslane extract on immuno-antioxidant status, intestinal barrier, and microbiota of chicks after experimental infection with Escherichia coli O78

This study focused on examining how Portulaca oleracea L. extract (POLE) influences production performance, antioxidant capacity, immunity, anti-apoptotic ability, and intestinal health in chicks exposed to Escherichia coli O78(E. coli). A 2 × 2 factorial design was used to randomly divide male chicks into 4 groups: (1) basal diet (CON group), (2) basal diet supplemented with 0.5 g/kg POL (CPOL group), (3) basal diet with E. coli challenge (ECON group), and (4) basal diet supplemented with 0.5 g/kg POL as well as E. coli challenge (EPOL group).The experiment lasted for 19 days. The POL supplementation was found to decrease the feed conversion ratio and liver and spleen indexes and increase the average daily gain and bursa indexes (P<0.05). Moreover, in chicks infected with E. coli, POL reduced the levels of serum DAO and caspase 8 (P<0.05). POL notably elevated the serum levels of immunoglobulins and IL-10, an anti-inflammatory cytokine, which also decreased the levels of proinflammatory cytokines TNF-α and IFN-γ. At the same time, dietary POL enhanced the mRNA expression of genes related to antioxidation and reduced the expression of genes associated with proinflammatory cytokines and apoptosis in the liver, spleen, jejunum, and ileum. In addition, dietary POL repaired the intestinal barrier and injury. More importantly, by boosting the abundance of beneficial bacteria such as Butyricicoccus and Blautia, and reducing harmful bacteria like Enterococcus and Escherichia, POL induced changes in the gut microbiota composition. Spearman's correlation study revealed that Dorea and Butyricoccus had a strong positive link with intestinal barrier function and antioxidant capacity, while Escherichia had a substantial positive correlation with pro-inflammatory cytokines. In summary, this study suggests adding POL to the diet as a beneficial supplement to enhance chick performance.