The immune (A2M, TLR2, TGF-β, IRAK3, CCl2, and iNOS), metabolic (ADAMTS20, KCNT2, MAP3K4, MAPK14, RXFP1, FKBP5, RXFP1 FCAMR, and EPHA4), and antioxidant (SOD3, CAT, GPX, and NDUFS5) genes in endometritis-affected and healthy Holstein dairy cows were characterized in this research using a PCR-DNA sequencing technique. This evidence concerns the gene CAT and endometritis.