Arula-7 powder improves diarrhea and intestinal epithelial tight junction function associated with its regulation of intestinal flora in calves infected with pathogenic Escherichia coli O 1

Background The effects of Arula-7 powder (ASP) on diarrhea and intestinal barrier function associated with its regulation of intestinal microflora in calves infected with pathogenic Escherichia coli O 1 ( E. coli O 1 ) were studied. Method Twenty Holstein calves were randomly divided into four treatment groups: normal control (NC), model control (MC), 0.5 mg/kg ciprofloxacin (CIP) and 2.50 g/kg ASP groups. Results ASP inhibited the relative abundance of Proteobacteria , Selenomonadales , and Enterobacteriales , and increased the relative abundance of Lactobacillus , Faecalibacterium , and Alloprevotella . Moreover, we demonstrated for the first time that the ASP and CIP promoted weight gain, reduced the diarrhea rate ( P < 0.05), and enhanced antioxidant capacity ( P < 0.05) due to the increase in average daily gain (ADG), total protein (TP), and albumin (ALB). In addition, ASP and CIP increased the expression of Zunola occludens-1 (ZO-1), Occludin, and Claudin-1 in the ileum ( P < 0.05), and improved immunity due to increase levels of interleukin-2 (IL-2), interleukin-4 (IL-4), interferon-γ (IFN-γ), immunoglobulin A (IgA), and immunoglobulin G (IgG) in the serum, strengthened CD4 + T levels in the ileal mucosa and reducing CD8 + T and CD11c + T ( P < 0.05). Conclusion Hence, The intestinal microbiota environment formed by early intervention of ASP powder has a protective effect on the intestinal mucosal function of calves infected with pathogenic E. coli . 4nw2EB1YynqDa4Tsj5-kjP Video Abstract