Five metabolic pathways, including KO00642 (ethylbenzene degradation), KO03320 (PPAR signaling pathway), KO00965 (betalain biosynthesis), KO05322 (systemic lupus erythematosus), and KO05131 (shigellosis), were significantly up-regulated in semi-free-range cranes compared to captive cranes, based on the third level of KEGG (p < 0.05) (Figure S2). Here, PPARA is linked to systemic lupus erythematosus.