This study is to explore the effects of natural tannin (NBT) on intestinal injury in piglets challenged with enterotoxigenic Escherichia coli (ETEC). Thirty-two 7-day-old piglets were divided into four groups: I) control group, piglets were fed a basic diet without challenge; II) ETEC group, piglets were fed a basic diet and challenged with enterotoxigenic E. coli; III) NBT + ETEC group, piglets were fed a basic diet with supplementation of 2 g/kg NBT and challenged with enterotoxigenic E. coli; and IV) ZnO + ETEC group, piglets were fed a basi...