Abstract: T-2 toxin is the most toxic trichothecene mycotoxin and can be present in many human foods and animal feeds. Currently, most of the studies related to the toxicology of T-2 toxin based on animal models are acute attack tests, but the contamination level of T-2 toxin in feed materials and livestock and poultry compound feeds is mostly low-level contamination. In this study, C57BL/6J mice were treated with 1 mg·kg^-1 BW T-2 toxin three times a week to assess its effects on the colonic barrier and the colonic flora. 100 mg·kg^-1 BW tannic acid (TA) was applied every day to ameliorate the toxicity of the T-2 toxin. T-2 toxin did not cause significant morphological damage and marked inflammatory responses in colonic tissue but significantly decreased the number of goblet cells in colon tissue (P<0.01). T-2 significantly downregulated the expression of mucoprotein Muc1 and the tight junction proteins Occludin, Claudin1, and ZO-1 (P<0.01). T-2 toxin changes the diversity of colonic flora in mice, the intervention of TA can make harmful bacteria in the colon of T2 group mice, such as Patescibacteria, Saccharimonadales, Candidatus-Saccharimonas, Odoribacter, Bilophila, and unclassified_f__Ruminoccaceae decreased significantly (P<0.05) or extremely significantly (P<0.01), while the abundance of beneficial microorganisms norank_f__Oscillospiraceae and Oscillibacter increased significantly (P<0.05) and extremely significantly (P<0.01) respectively. In summary, a low-dose T-2 toxin exposure will lead to the impaired colonic barrier and dysbiosis of colonic flora in mice, and TA treatment can alleviate T-2 toxin-induced colonic mucosal damage and improve intestinal health in mice.

Key words: T-2 toxin, tannic acid, antinutritional factors, intestinal barrier, intestinal flora