CXCL8 and susceptibility to pneumonia measurement: Animal serum inflammatory factors were elevated; IL-6 can enhance effect of other cytokines; IL-8 can attract and activate neutrophils; IL-12 can act on T cells and NK cells; TNF-α can resist infection and action as an endogenous heat source; RDA redundancy analysis of intestinal contents of four groups animals suggested that in structure of microorganism, high calorie diet combined with pneumonia enhanced effect of cytokines leading to inflammation and inhibits autoimmunity.