Protective effects of α-terpineol and Bacillus coagulans on intestinal function in weaned piglets infected with a recombinant Escherichia coli expressing heat-stable enterotoxin STa

This study was to investigate the impact of α-terpineol (α-TPN) and Bacillus coagulans (B. coagulans) on weaned piglets infected with Enterotoxigenic Escherichia coli (ETEC). Thirty-two weaned piglets were assigned into four treatments: Control group (basal diet), STa group (basal diet + 1 × 10(10) CFU ETEC), TPN+STa group (basal diet + 0.01% α-TPN + ETEC) and BC+STa group (basal diet + 2 × 10(6) CFU B. coagulans + ETEC). Result showed that both α-TPN and B. coagulans could alleviate diarrhea (decreased diarrhea rate), intestinal injury (improved intestinal morphology, decreased blood I-FABP concentration, increased protein expression level of Occludin), oxidative stress (increased GSH-Px activity and decreased MDA content) and inflammation (altered concentration of TNF-α, IL-1β in blood) induced by ETEC infection. Mechanism investigation further demonstrated that the beneficial effects of α-TPN and B. coagulans supplementation upon ETEC infection may be achieved by decreasing the protein expression levels of caspase-3, AQP4 and p-NF-κB and decreasing the gene expression levels of INSR and PCK1. Besides, α-TPN supplementation could specifically decreased expression level of gene b(0,+)AT, and B. coagulans supplementation could specifically decreased expression level of gene AQP10 and protein HSP70 in ETEC-infected weaned piglets. These results suggested that α-TPN and B. coagulans can be used as antibiotic alternatives against ETEC infection in weaned piglets.