The zebrafish (Danio rerio) is a popular vertebrate model organism used in a wide range of research fields. Importance is placed on zebrafish health and the maintenance of disease-free laboratory fish so that experimental studies are not inadvertently impacted. Mycobacteriosis is a common infection of laboratory zebrafish that is caused by several Mycobacterium species. Little is known regarding the potential of antibiotic treatment for zebrafish mycobacteriosis; however, treatment of infected zebrafish may be appropriate to maintain valuable strains. Here, we investigate the antibiotic susceptibility of both rapid and slow growing zebrafish Mycobacterium spp. isolates in vitro. Antibiotic testing was carried out using a commercially available 96-well microtiter plate format. Results indicate that some but not all antibiotics tested are effective at inhibiting mycobacterial growth and that susceptibility varies among species and strains. Tigecycline, tobramycin, clarithromycin and amikacin were most effective at broad inhibition of rapid-growing mycobacteria; whereas, amikacin, clarithromycin, and rifampin were effective at inhibiting all slow-growing Mycobacterium marinum strains tested. Results support the potential for targeted antibiotic treatment of zebrafish infected with mycobacteria, but additional in vivo testing should be carried out.
Mycobacteriosis is a bacterial disease that is common in captive, wild and research fish. There is no one causative agent of mycobacteriosis, as several strains and species of Mycobacterium have been identified in zebrafish. With increased usage and investment in wild-type and mutant zebrafish strains, considerable value is placed on preserving zebrafish health. One control measure used to prevent mycobacterial spread within and between zebrafish facilities is egg disinfection. Here we investigate the effectiveness of three disinfectants [chlorine bleach, hydrogen peroxide, and povidone iodine (PVPI)] commonly included in egg disinfection protocols for laboratory fish as well as aquaculture fish and compare the knockdown effect of these treatments on Mycobacterium spp. in vitro. Despite current usage, comparison of these disinfection regimes’ abilities to prevent mycobacterial growth has not been tested. We found that the germicidal effect of different disinfectants vary by Mycobacterium spp.. Hydrogen peroxide was the least effective disinfectant, followed by unbuffered chlorine bleach, which is commonly used to disinfect embryos in zebrafish facilities. Disinfection with 25 ppm PVPI for 5 min was very effective, and may be an improved alternative to chlorine bleach for embryo disinfection. Results from this study can be utilized by laboratory fish facilities in order to prevent the spread of mycobacteriosis in research fish.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.