| Summary: | Carbapenem resistance has posed potential harmful risks to human and animals. The objectives of this study were to understand the prevalence of <i>bla</i><sub>NDM-5</sub> in pigs and investigate the molecular characteristics of NDM-5-producing <i>Escherichia coli</i> isolates in Guangdong province in China. Carbapenem-resistant <i>E. coli</i> isolates were isolated from pigs and obtained using MacConkey plates containing 0.5 mg/L meropenem. Conjugation assay and antimicrobial susceptibility testing were conducted for the isolates and their transconjugants. Whole-genome sequence (WGS) was used to analyze the plasmid genetic feature. A total of five <i>bla</i><sub>NDM-5</sub>-carrying <i>E. coli</i> isolates were obtained in the present investigations. They belonged to five ST types. The <i>bla</i><sub>NDM-5</sub> genes were found to be in IncX3 and IncHI2 plasmid. The IncX3 plasmid was 46,161 bp in size and identical to other reports. IncHI2 plasmid was 246,593 bp in size and similar to other IncHI2-ST3 plasmids. It consisted of a typical IncHI2 plasmid backbone region and a multiresistance region (MRR). The <i>bla</i><sub>NDM-5</sub> was closely associated with the <i>IS3000-ISAba125-blaNDM-5-bleMBL-trpF-tat-IS26</i> unit. We first reported the <i>bla</i><sub>NDM-5</sub>-carrying IncHI2 in <i>E. coli</i> isolates recovered from pigs and revealed the molecular characterization. Continued surveillance for the dissemination of <i>bla</i><sub>NDM-5</sub> among food-producing animals is required.
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