Use of acoustic stimulus to determine behavioral changes in zebrafish after Cd exposure in a water quality warning system.

Behavioral changes in zebrafish are an effective early warning system to determine water quality. However, only a few studies have examined the response of zebrafish to non-chemical stimulus after exposure to a contaminant. Therefore, this study investigated the differences in the behavioral responses of zebrafish to acoustic stimuli before and after exposure to cadmium (Cd). Acoustic escape response sensitivity curves were obtained and analyzed, followed by the determination of sensitive stimulus conditions at 100 Hz and 97 dB with a duration of 30 s and an interval of 30 min. Zebrafish exhibit a significant acoustic escape response, which is significantly reduced after exposure to Cd. The results showed that zebrafish stop demonstrating acoustic escape responses when exposed to higher Cd concentrations or longer acoustic exposures. Based on these results, a novel method for detecting abnormal behavior in zebrafish by acoustic stimulation has been proposed, which is expected to reduce the false alarm rate of this type of water quality technology.