Microbial Isolation and Comparison of Antibiotic Resistance Pattern in Rainbow Trout (Oncorhynchus mykiss) from Chaharmahal-va-Bakhtiari Province, Iran (۲۰۲۲-۲۰۲۳)

Background: Increased antibiotic resistance due to the overuse and misuse of antibiotics is a severe threat to both the aquaculture industry and human health. This study aimed to determine the antibiotic resistance pattern of bacteria isolated from rainbow trout. Materials & Methods: A total of ۷۹ and ۱۲۰ fish samples were collected in ۲۰۲۲ and ۲۰۲۳, respectively. Swab samples were enriched in TSB (tryptic soy broth) and cultured on TSA (tryptic soy agar). The grown colonies were evaluated for Aeromonas hydrophila, Lactococcus garvieae, Streptococcus iniae, and Yersinia ruckeri. Antibiotic resistance patterns against ۱۰ common antibiotics were evaluated. Findings: In this study, four types of bacteria (A. hydrophila, L. garvieae, S. iniae, and Y. ruckeri) were isolated. The results of antibiotic resistance analysis during ۲۰۲۲-۲۰۲۳ showed that in all isolated bacteria, the percentage of antibiotic resistance against enrofloxacin and florfenicol was higher in ۲۰۲۳ than in ۲۰۲۲. Conclusion: The isolated bacteria had different resistance patterns, these patterns could be used as a guide for selecting appropriate antibiotics to control infectious diseases in rainbow trout. This finding may be due to improper administration of these antibiotics in rainbow trout production.

کلیدواژه ها:

Drug resistance ، Oncorhynchus mykiss ، Aquaculture