Acta Veterinaria et Zootechnica Sinica ›› 2021, Vol. 52 ›› Issue (9): 2561-2568.doi: 10.11843/j.issn.0366-6964.2021.09.019

• PREVENTIVE VETERINARY MEDICINE • Previous Articles     Next Articles

Analysis of Epidemiological Characteristics of Clinical Staphylococcus pseudintermedius Isolated from Dogs

ZHANG Haixia, ZHANG Zhenbiao, DAI Hegen, SONG Yu, LI Lei, XIA Zhaofei*   

  1. College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
  • Received:2020-12-28 Online:2021-09-23 Published:2021-09-26

Abstract: This study aimed to investigate the antimicrobial resistance phenotype, genotype, and molecular characteristics of Staphylococcus pseudintermedius isolated from clinical samples in dogs. From November 2017 to April 2019, 601 samples were collected from the Veterinary Teaching Hospital of China Agricultural University (VTH-CAU) and third-party testing organizations, and identified by PCR amplification of 16S rDNA gene sequencing. Antimicrobial susceptibilities of S. pseudintermedius strains were determined by agar microdilution method according to the CLSI recommendations. All strains were subjected to whole genome sequencing (WGS). Then resistant genes, multilocus sequence typing (MLST), SCCmec types were deduced from WGS data. A total of 75 (12.5%) S. pseudintermedius were isolated from all clinical samples, including 42 (56%) methicillin-resistant S. pseudintermedius (MRSP) and 33 (44%) methicillin-susceptible S. pseudintermedius (MSSP). All of S. pseudintermedius were highly resistant to penicillin, azithromycin, clindamycin, doxycycline, enrofloxacin, ciprofloxacin, chloramphenicol and oxacillin; and were sensitive to linezolid, vancomycin, amikacin and rifampicin. Multi-drug-resistant (MDR) rate of 75 S. pseudintermedius were 90.7% (n=68/75), while all of MRSP isolates (100%, n=42/42) were MDR. Nineteen antimicrobial resistanct genes were detected by WGS. The detection rate of blaZ and aac(6')-aph(2″) were the highest, both were 92% (69/75). A total of 70 sequence types (STs) were detected, and 54 were novel. There were no dominant STs in this study. Among 42 MRSP isolates, 23 (54.7%) belong to staphylococcal cassette chromosome mec (SCCmec) V. This study showed that MDR of MRSP and MSSP were both high, which presents very important issue that MDR-MSSP cannot be ignored; and high genetic diversity among S. pseudintermedius exhibited in China.

Key words: dog, Staphylococcus pseudintermedius, multidrug-resistant, antimicrobial resistance genes, molecular typing

CLC Number: