| Sumario: | To investigate the prevalence and resistance against antimicrobials of<italic> Escherichia coli (E. coli)</italic> in Tai’an, March 2016, a total of 55<italic> E. coli</italic> strains were isolated from 60 faecal samples of diarrheic rabbits collected from three rabbit farms in Tai’an. The<italic> E. coli</italic> isolates were assayed for antimicrobial susceptibility and prevalence of resistance genes and Class I integrons and genotyped using Multilocus Sequence Typing (MLST). All the<italic> E. coli</italic> isolates were sensitive to ceftazidime, ceftriaxone, imipenem, and amikacin, while 78.2% of the isolates showed resistance against tetracycline, and 65.5% were resistant against ampicillin. The most common resistance gene detected was blaTEM, present in 98.2% of isolates, followed by blaCTX-M (94.6%) and<italic> sul2</italic> (58.2%). Class I integrons were detected in 17 out of the 55 (30.9%)<italic> E. coli</italic> strains. Seven kinds of gene cassette were detected:<italic> dfrA17</italic> +<italic> aadA5</italic>,<italic> dfrA1</italic> +<italic> catB3</italic> +<italic> aacA4</italic>,<italic> aadA2</italic> +<italic> LinF</italic>,<italic> dfrA1</italic> +<italic> aadA1</italic>,<italic> aadA22</italic>,<italic> dfrA12</italic> +<italic> orfF</italic> +<italic> addA2</italic>, and<italic> aadA16</italic> +<italic> dfrA27</italic> +<italic> arr-3</italic>. All the 55<italic> E. coli</italic> strains were identified and classified as 13 sequence types (STs); ST302 (22/55, 40.0%) was the most prevalent type, followed by ST370 (12/55, 21.8%). This study showed that<italic> E. coli</italic> isolated from diarrheic farmed rabbits in the Tai’an area exhibit sometimes very frequent resistance to antimicrobials important to human medicine, which further highlights the need for reasonable use of antibiotics.
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