In Cpn group, infection induced down-regulation of acetyl-Coenzyme A acyltransferase 2 (Acaa2, FC = 0.41), ELOVL family member 6, elongation of long chain fatty acids (Elovl6, FC = 0.44), and nuclear receptor subfamily 1, group D, member 2 (Nr1d2, FC = 0.44) (Additional file 3: Table S3). The gene discussed is CPN1; the disease is infection.