LAUSR

Abstract Tricaine is a widely-used compound in the anesthesia of fish in both aquaculture and research laboratories. Studies on fish reproduction to date suffer from the impact of anesthetics used for euthanasia, especially the quality of gametes. Therefore, this study aims to analyze the effect of the different concentrations of tricaine (0, 200 and 400 mg/L) on sperm kinetics parameters, structural parameters of plasma membrane fluidity and integrity, production of reactive oxygen species, mitochondrial functionality, lipoperoxidation and DNA fragmentation index by flow cytometry method. Our results showed that the concentration of 400 mg/L tricaine (MS-222) can be used to euthanize Danio rerio even in experiments with reproductive parameters, for humanitarian reasons and avoiding animal suffering, once this concentration has not influenced kinetic parameters like sperm, plasma membrane functionality, DNA fragmentation index, reactive oxygen species and lipoperoxidation.