We characterized 67 Escherichia coli isolates with reduced susceptibility to cefotaxime or ceftiofur obtained from healthy broilers housed in five Italian farms. The bla _CTX-M-1 , bla _CTX-M-32 and bla _SHV-12 β-lactamase genes were identified on IncI1, IncN, or IncFIB plasmids. Considerable genetic diversity was detected among the extended-spectrum β-lactamase (ESBL)-producing isolates, and we identified indistinguishable strains in unrelated farms and indistinguishable plasmids in genetically unrelated strains. The detection of highly mobile plasmids suggests a potential animal reservoir for β-lactamase genes.

Aims: The prevalence, level of contamination and epidemiological profile of Listeria monocytogenes were investigated in two meat‐producing plants during a 20‐month period. Methods and Results: Sampli...