Gene expression of innate Th1-, Th2-, and Th17-type cytokines during early life of neonatal foals in response to Rhodococcus equi

► We examined Th-type cytokine mRNA expression in foals during the first 3 weeks of life. ► IFN-γ (Th1) mRNA expression in response to Rhodococcus equi did not change with age. ► IL-4 (Th2) mRNA expression in response to R. equi was significantly lower at birth. ► IL-17 (Th17) mRNA expression in response to R. equi increased with age. ► R. equi strongly induced IL-17 mRNA expression by bronchial cells and PBMCs.