The study identifies multiple antimicrobial resistance genes on plasmids pSC138 and pSCV50 in Salmonella enterica serovar Choleraesuis SC-B67, including blaTEM-1, blaCMY-2, tetRA, strA, aadA2, sulI, sulII, catI, cmlA, aph, sat, mef, mer, ebr, qac, and blaTEM-67. Additionally, mutations in the chromosomal genes gyrA and parC, along with the inactivation of acrR, contribute to ciprofloxacin resistance.