Thesis Magali Naviner

Magali Naviner

Emergence and persistence of resistant bacteria in rainbow trout (Oncorhynchus mykiss) farms undergoing antimicrobial treatment

Summary of the thesis :

The objective of this study was to evaluate the consequences of the use of oxolinic acid (AO) or flumequine, antibiotics of the quinolone family commonly used in France for the treatment of rainbow trout, on the evolution of resistance of indicator bacteria in these fish and in fish farming, and the possible contamination by these resistant bacteria of fish products intended for human consumption. The choice of Aeromonas spp. as sentinel bacteria for the evolution of antimicrobial resistance within the trout microflora and its environment was found to be relevant (ease of isolation, diversity of antimicrobial susceptibility profiles) but of limited application for the gut compartment due to large seasonal quantitative variations. The objective of this study was to evaluate the consequences of the use of oxolinic acid (AO) or flumequine, antibiotics of the quinolone family commonly used in France for the treatment of rainbow trout, on the evolution of resistance of indicator bacteria in these fish and in fish farming, and the possible contamination by these resistant bacteria of fish products intended for human consumption. The choice of Aeromonas spp. as sentinel bacteria for the evolution of antimicrobial resistance within the trout microflora and its environment was found to be relevant (ease of isolation, diversity of antimicrobial susceptibility profiles) but of limited application for the gut compartment due to large seasonal quantitative variations.