The pig endometritis increased the PGE2, PGF2α and PGI2 amounts in the endometrium and myometrium [11,12], and the endometrial expression of PG-endoperoxidase synthase-2 (PTGS-2, also known as PGHS-2 or COX-2) [11,13,14] and microsomal PTGE synthase-1 (mPTGES-1, also known as mPGES-1; enzyme down streaming PTGS-2, terminating PGE2 synthesis) [15]. The gene discussed is PTGS2; the disease is endometritis.