Baicalin-aluminum alleviates necrotic enteritis in broiler chickens by inhibiting virulence factors expression of .

type A is the main cause of necrotic enteritis (NE) in chickens. Since the use of antibiotics in feed is withdrawn, it is imperative to find out suitable alternatives to control NE. Baicalin-aluminum complex is synthesized from baicalin, a flavonoid isolated from Georgi. The present study investigated the effects of baicalin-aluminum on the virulence-associated traits and virulence genes expression of CVCC2030, it also evaluated the therapeutic effect on NE. The results showed that baicalin-aluminum inhibited bacterial hemolytic activity, diminished biofilm formation, attenuated cytotoxicity to Caco-2 cells, downregulated the expression of genes encoding for clostridial toxins and extracellular enzymes such as alpha toxin (CPA), perfringolysin O (PFO), collagenase (ColA), and sialidases (NanI, NanJ). Additionally, baicalin-aluminum was found to negatively regulate the expression of genes involved in quorum sensing (QS) communication, including genes of Agr QS system (, ) and genes of VirS/R two-component regulatory system (, ). experiments, baicalin-aluminum lightened the intestinal lesions and histological damage, it inhibited pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) expression in the jejunal and ileal tissues. Besides, baicalin-aluminum alleviated the upregulation of and and raised the relative abundance of in the ileal digesta. This study suggests that baicalin-aluminum may be a potential candidate against infection by inhibiting the virulence-associated traits and virulence genes expression.