Mean frequencies CD3+CD4+ (A) and CD3+CD8+ (B) T cells among mononuclear cells (MNCs) and CD4+CD25+Foxp3+ (C,D) among CD4 T cells in vitamin A deficient (VAD) and sufficient (VAS) pigs vaccinated with AttHRV vaccine or placebo with or without vitamin A supplementation in blood, spleen, ileum and duodenum post-virulent HRV challenge Bars represent mean values and standard error of the mean. Significant differences between groups are indicated by capped lines as determined by non-parametric Kruskal-wallis rank sum test (p ≤ 0.05). Vac = 3X AttHRV vaccinated only, Vac+VitA = 3X AttHRV vaccinated + 100,000 IU of vitamin A, Ctrl = non-vaccinated and non-vitamin A supplemented, Ctrl+VitA = 3X 100,000 IU of vitamin A only.