Antimicrobial susceptibility and genetic relatedness of Salmonella enterica subsp enterica serovar Mbandaka strains, isolated from a swine finishing farm in Greece

The current study investigated the antimicrobial susceptibility of Salmonella enterica subsp. enterica serovar Mbandaka ( Salmonella Mbandaka) isolated from finishing swines in Greece. Pulsed-field gel electrophoresis (PFGE) was used to examine the genetic relatedness of the isolates. The study was carried out for 1 year as part of a project focusing on antimicrobial resistance of salmonellae recovered from asymptomatic pigs. A total of 400 finishing pigs stabled in 20 swine farms in central Greece were included in the study. Fecal samples taken directly from the rectum, one sample from each pig, were cultured for Salmonella spp. Five of the 400 tested finishing pigs, originating from the same herd, were asymptomatic carriers of Salmonella Mbandaka. All five isolates were resistant to tetracycline, four were resistant to trimethoprim/sulfamethoxazole, and three to ampicillin and amoxicillin/clavulanic acid. In contrast, all five isolates were susceptible to cefuroxime and ceftriaxone, as well as to nalidixic acid, ciprofloxacin, and levofloxacin. All five isolates had indistinguishable PFGE patterns. The present study confirms the existence of a nontyphoid Salmonella serotype, Salmonella Mbandaka in asymptomatic carrier pigs in Greece. Further, the Salmonella Mbandaka isolates were found to be resistant to several antimicrobials