Virulence Gene Profiling and Antibiotic Resistance Analysis of Clostridium perfringens from Farmed Sika Deer in Northern China

Clostridium perfringens is an important zoonotic pathogen that can be carried by both humans and small ruminants. This study aimed to investigate the virulence gene profiles and antibiotic resistance characteristics of C. perfringens isolates from farmed sika deer. A total of 10 isolates were obtained from fecal samples, with an overall isolation rate of 2.59%. All strains were identified as type A. Antimicrobial susceptibility testing revealed varying degrees of resistance to tetracycline (10%), tigecycline (50%), penicillin (50%), clindamycin (50%), and metronidazole (50%). Whole-genome sequencing identified 12 virulence-associated genes (including nagK, nagH, colA, cloSI, plc, and pfoA) and 8 resistance genes (tetA(P), tetB(P), ermQ, mprF, etc.). Molecular typing by multilocus sequence typing and core genome multilocus sequence typing uncovered limited clonal spread and substantial genetic diversity, with the majority of isolates (7/10) representing novel sequence types. These findings provide new insights into the genomic characteristics of C. perfringens in farmed sika deer and underscore the potential public health and animal health risks associated with antimicrobial-resistant strains.