Knowledge Base

Problem

DanioVision experiment results show many zeros across wells or time points, indicating tracking failures or missing data during zebrafish larvae VMR (visually mediated response) recordings.

Details

Zeros in exported DanioVision data represent either samples where tracking failed (animal not detected) or time points where no movement data was recorded. This can result from poor contrast, lighting issues, incorrect detection settings, or wells where larvae are absent or not moving. Once data has been exported to Excel, the zeros cannot be corrected retroactively – the tracking data itself must be re-examined. The experiment must be in DanioVision mode in EthoVision for hardware integration and correct detection options to be available.

Solution

1. Confirm that the EthoVision experiment is configured in DanioVision mode (not a standard experiment). This enables the correct detection settings and hardware integration for the DanioVision system.
2. Open the affected trials in EthoVision and review the tracking video to identify wells/time points where tracking failed.
3. Check detection settings: adjust contrast thresholds, brightness, or subject size parameters to improve detection reliability in problematic wells.
4. Verify that the DanioVision white light or IR illumination is functioning correctly and evenly illuminating the plate.
5. If tracking failures are confirmed, retrack the affected trials with corrected detection settings.
6. In the exported data layout, you can hide empty/zero fields using the 'Layout' menu if you wish to suppress display of missing data, but this does not recover lost tracking information.
7. For systematic zeros in specific wells, inspect whether larvae were present and viable in those wells during recording.