Imported ornamental fish are colonized with antibiotic-resistant bacteria

Area of Science:

• Aquatic microbiology
• Veterinary medicine
• Antimicrobial resistance

Background:

• Growing concern over antibiotic overuse in the ornamental fish industry.
• Potential impact on antimicrobial resistance in fish pathogens and commensals.
• Need for understanding bacterial diversity and resistance in imported fish.

Purpose of the Study:

• Assess bacterial diversity and antibiotic resistance in imported ornamental fish.
• Identify potential fish and human pathogens.
• Inform treatment strategies and zoonotic risk.

Main Methods:

• Kidney samples from 32 freshwater ornamental fish from diverse origins.
• Bacterial isolation and identification using PCR and 16S rRNA gene sequencing.
• Antibiotic resistance profiling against nine different antibiotics.

Main Results:

• Sixty-four unique bacterial isolates identified, including potential pathogens.
• Significant antibiotic resistance observed, with tetracycline resistance at 77% and cefotaxime resistance at 16%.
• Identification of bacteria with potential to cause disease in both fish and humans.

Conclusions:

• Imported ornamental fish harbor diverse bacteria with varying antibiotic resistance profiles.
• Findings are crucial for effective treatment of infected fish and managing potential zoonotic diseases.
• Highlights the need for responsible antibiotic use in aquaculture.