Mechanisms of antimicrobial resistance in finfish aquaculture environments

Abstract

Consumer demand for affordable fish drives the ever-growing global aquaculture industry. The intensification and expansion of culture conditions in the production of several finfish species has been coupled with an increase in bacterial fish disease and the need for treatment with antimicrobials. Understanding the molecular mechanisms of antimicrobial resistance prevalent in aquaculture environments is important to design effective disease treatment strategies, to prioritize the use and registration of antimicrobials for aquaculture use, and to assess and minimize potential risks to public health. In this brief article we provide an overview of the molecular mechanisms of antimicrobial resistance in genes found in finfish aquaculture environments and highlight specific research that should provide the basis of sound, science-based policies for the use of antimicrobials in aquaculture.

Serotype distribution and antimicrobial susceptibilities of Streptococcus agalactiae isolated from infected cultured tilapia (Oreochromis niloticus) in Thailand: Nine-year perspective

“…Similar resistant phenotypes of GBS were reported in silver pomfret (Pampus argenteus) cultured in Kuwait (Duremdez et al, 2004). Generally, resistance to oxolinic acid, a member of the quinolone family, is primarily mediated by chromosomal mutations in topoisomerase genes and mutations that decrease drug accumulation by reducing uptake or increasing efflux (Miranda et al, 2013), while resistance to gentamicin by GBS is mediated by the production of aminoglycoside-modifying enzymes 69-acetyltransferase and 29-phosphotransferase (Buu-Hoï et al, 1990). Sulfamethoxazole and trimethoprim are used in combination as the drug co-trimoxazole (Schmitz al., 2001).…”

Impacts of rearing techniques on growth, survival and bacterial microbiota of carpet shell clam (Ruditapes decussatus) larvae

“…However, several reports have demonstrated that the extensive use of antibiotics in aquaculture could facilitate the emergence and the selection of resistant bacteria (Laganà et al 2011;Mechri et al 2015). Previous studies of antimicrobial resistance in fish pathogenic bacteria have reported the occurrence of the floR gene as the major facilitator superfamily and code for efflux proteins that export florfenicol out of the cell (Miranda et al 2013;Schwarz et al 2004). Recently, Miranda et al (2015) found that most of gram-negative bacteria associated with scallop hatcheries carried the floR gene.…”

“…FF is a fluorinated derivative of thiamphenicol with an expanded spectrum of activity and enhanced potency but with less harmful effects (Samuelsen and Bergh 2004;Xu et al 2005). Thus, FF is often used to control bacterial disease outbreaks in mollusk larval hatcheries (Torkildsen et al 2002;Torkildsen and Magnesen 2004;Miranda et al 2013). However, several reports have demonstrated that the extensive use of antibiotics in aquaculture could facilitate the emergence and the selection of resistant bacteria (Laganà et al 2011;Mechri et al 2015).…”

Campylobacter: fluoroquinolone resistance in Latin-American countries

“…This excessive use probably may facilitate selection of resistant aquatic bacteria and others bacteria of medical importance associated with marine activity. Miranda et al (2013) referred that various point mutations in the quinolone resistance-determining regions of the gyrA and/ or parC genes have been detected in quinolone-resistant strains of fish pathogens such as Aeromonas hydrophila, Vibrio anguillarum, V. parahaemolyticus and Edwardsiella tarda. These bacteria have also been associated to human infections.…”