The impact of ZnO as a feed additive on growth-performance and intestinal function of Enterotoxigenic Escherichia coli (ETEC) K88-infected piglets remains unclear. Fecal scores of piglets in ETEC group were significantly increased compared to control group. ETEC K88 significantly damages the small intestine, including a reduction in villus height in the jejunum, duodenum, and ileum, and a decrease in total superoxide dismutase activity in the jejunum and catalase activity in the ileum and jejunum. Compared to control group, ETEC K88 infection s...