IL2 and inflammatory response: Furthermore, according to the expression of intestinal inflammatory cytokines, the supplementation with starter feeding could increase the expression of some proinflammatory cytokines, including the IL-2, TNF-α, and IFN-γ (Maggioli et al., 2016), which indicated that the grain feed supplementation could increase the occurrence of intestinal inflammation, stimulate the differentiation of immune cells, and enhance the immune function.