Extended spectrum β-lactamase SHV-12-producing Salmonella from poultry

Salmonella strains isolated from poultry and poultry products over the period 2005–2006 have been investigated in order to ascertain the presence of extended spectrum cephalosporins (ESC) resistance. Twelve (ESC)-resistant isolates (n = 1 S. Enteritidis, n = 1 S. Braenderup and n = 10 S. Livingstone) were characterized as SHV-12-positive. The multi-drug resistant S. Livingstone SHV-12-producing isolates, untypeable by pulsed-field gel electrophoresis (PFGE), showed a clonal relationship by random amplified polymorphic DNA (RAPD) analysis. The SHV-12 β-lactamase is reported for the first time in Salmonella enterica strains isolated from poultry in Italy. The results suggest poultry as a source of Salmonella carrying extended spectrum β-lactamases (ESBLs) genes and highlights the need of monitoring animal productions to prevent spreading of (ESC)-resistant strains.