DON caused intestinal barrier disruption and reduction of IPEC-J2 cell viability. IPEC-J2 cells were treated with DON (0, 2, or 5 μg/mL) for 0, 24, 48 or 72 h. A TEER values were measured using epithelial voltohm meter at indicated time points. Data represent mean ± SD of TEER (n = 4). B Viability of the cells was examined by MTT assay at 48 and 72 h after DON treatment (n = 3). *P < 0.05, **P < 0.01, and ***P < 0.001 001, determined by (A) two-way ANOVA with Bonferroni’s posttest, or (B) one-way ANOVA with Tukey’s posttest. To examine the expression of tight junction proteins, IPEC-J2 cells were treated with DON (0, 0.2 and 2 μg/mL) for 24, 48, or 72 h. Whole-cell lysates were analyzed for the expression of (C) Claudin-3, ZO-1 and β-actin by using Western blot assay. The representative figure from three similar results is shown. D ZO-1 expression in IPEC-J2 was visualized using confocal microscopy after staining with anti-ZO-1 antibody conjugated with Alexa fluor 488-FITC (green) and nuclei (DAPI; blue) (n = 3). Scale bar = 50 μm.