IL4 and infection: In this study, yellow cattle and water buffalo were artificially infected with S. japonicum cercariae, and at different times post infection(0 weeks [w], 2w, 4w, 7w), the CD4+ and CD8+ T cell subsets and the intracellular cytokines interferon-γ(IFN-γ) and interleukin-4(IL-4) in the peripheral blood, as well as specific serum IgG antibodies, were detected and analyzed.