Changes in aggressive behaviors and testosterone concentration of fighting fish Betta splendens, exposed to fluoxetine

The present study was aimed to investigate the effect of fluoxetine on aggressive behaviors towards female and testosterone concentration of male fighting fish (Betta splendens) during one reproduction event. Male specimens were exposed 6 days to concentrations of 0 (control treatment) and 0.54 µg/L fluoxetine (exposed treatment) and aggressive behaviors of them assessed on different reproductive phases consisted of before bubblenest, after bubblenest, after spawning and after hatching. After 6 days, testosterone concentrations of exposed treatment decreased significantly compared to control treatment. Aggressive behaviors were affected by fluoxetine in most reproductive phases; the number of sweeps to the nest after bubblenest and after spawning was significantly different between treatments. The results of present study indicate that fluoxetine in low concentration (0.54 µg/L) with affect on endocrine system of fighting fish reduced whole body testosterone and aggression of male encountered females during reproduction.