The objective of this study is to comparatively analyze the effect of S. Enteritidis and S. Heidelberg infection on CD4+CD25+ T regulatory cell properties and CD4+CD25- T cells in chickens between 4 to 32 dpi to identify if infection with two different serovars of Salmonella can induce host immune cells properties in an antigen-specific pathway. This evidence concerns the gene CD4 and infection.