Zebrafish aversion to infrasound in an open field test

Area of Science:

• Aquatic toxicology
• Bioacoustics
• Environmental science

Background:

• Aquatic species detect infrasound (sub-20 Hz), a form of anthropogenic pollution.
• Infrasound from infrastructure may impact the wellbeing of aquatic laboratory animals.
• Human inaudibility of infrasound necessitates investigation into its effects on aquatic life.

Purpose of the Study:

• To investigate the behavioral responses of zebrafish (Danio rerio) to infrasound exposure.
• To determine if infrasound impacts fish movement, location preference, or immobility.
• To assess the potential aversive effects of specific infrasound frequencies on zebrafish.

Main Methods:

• Wild-type zebrafish were exposed to infrasound at 5, 10, 15, or 20 Hz, with a 0 Hz control group.
• Motion-tracking software quantified fish movement, arena location, distance moved, and immobility during open field tests.
• Behavioral data were analyzed to identify significant differences between infrasound-exposed and control groups.

Main Results:

• A significant effect was observed at 15 Hz, with zebrafish spending more time away from the infrasound source.
• The 20 Hz group exhibited significantly less time in the zone closest to the speaker.
• No significant differences in total distance moved or immobility were found between infrasound and control groups.

Conclusions:

• Infrasound at 15 Hz demonstrates aversive properties in zebrafish, prompting avoidance behavior.
• Findings suggest infrasound pollution can negatively affect aquatic animal wellbeing.
• Mitigation of infrasound sources is recommended to improve environmental enrichment for aquatic laboratory animals.