Knowledge Base

Acquire Data

There are three ways of acquiring data with your DanioVision system. For every option it is possible to run single trials, but it is also possible to carry out batch acquisition.

• Acquire data live. The larvae are tracked as they move in their wells.
• Acquire data live and record video simultaneously. The larvae are tracked as they move in their wells while at the same time a video is recorded. This gives you the opportunity to redo the tracking if necessary, either per trial or using batch acquisition.
• Record video, then acquire data. You record a video first and then track the subjects offline from the video. Please note that if you only record video with EthoVision XT, Trial Control is not applied. So, for example, the white light is not switched on and off if you only record video.

Before you start acquiring data, make sure you have carried out all the necessary checks of the system.

Notes:

• The DanioVision Observation Chamber is designed to block light from the outside. However, it cannot be guaranteed that it is completely dark inside the chamber. For experiments that require absolute darkness, place the DVOC in a dark room.
• Important: In long experiments, evaporation may occur for both the wells in the plate and the basin. Check the wells every 24 hours and if necessary, refill them. Refill the basin every 2–3 days using the Basin Refill tool.

Acquire Data Live

1. Make sure the camera is connected to the EthoVision XT computer and that Live tracking is selected as Video Source in the Experiment Settings.
2. Optionally, plan your trials in the Trial list and select the Arena settings, Detection settings, and Trial Control settings for each trial.
3. Choose Acquisition > Open Acquisition.
4. If no trials are planned, click the New trial button in the Playback Control window or press Ctrl+F3.
5. In the Acquisition Settings pane, select whether you want to track only the next planned trial or whether you want to track all planned trials without having to start the next trial manually. If you want to track all planned trials, specify the inter-trial interval. Enter a time long enough to be able to change well plates. When you change the well plate between trials, you can start the next trial without waiting for the inter-trial interval to be reached by clicking the Skip remaining interval button in the Playback Control window.
6. Select whether you automatically want to start the analysis after the tracks are acquired. If that is the case, first define your dependent variables in an Analysis Profile. Optionally, first make a Track Smoothing profile and a Data profile to make a selection out of your data.
7. Select whether you want to use the Track Smoothing profile, Data profile, and Analysis profile that are highlighted in blue in the Experiment Explorer for analysis, or whether you want to run analyses for all possible profile combinations. In the latter case, first delete all profiles you do not need for analysis. If you want to carry out analyses for only a selection of profiles, deselect the check box Auto-start analysis and carry out batch analysis after acquisition.
8. Put the well plate into the DanioVision chamber.
9. Click the Auto-detect button. A Re-initialize window with a timer appears. Wait until it disappears. Important: Use the Auto-detect button every time you change a well plate.
10. To start the trial, click the Start trial button in the Playback Control window or press Ctrl+F5.
11. To stop the trials, wait until Trial Control automatically stops the trials. To stop acquisition manually, click the Stop trial button in the Playback Control window or press Ctrl+F6. If you stop the trials manually, automatic analysis does not start. Also, for batch analysis, the next trials are not started if you stop a trial manually.

Note: The recommended maximum trial duration when acquiring live without recording video is 72 hours (3 days).

Acquire Data Live and Record Video Simultaneously

To save video when doing tracking, follow the procedure above, with the difference that you select the check box Save video in the Acquisition Settings pane.

If you realize tracking was not optimal, you can redo tracking from the acquired video.

Note: The recommended maximum trial duration when acquiring live and recording video simultaneously is 60 minutes. Longer trials produce video files of excessive size that are more difficult to manage. Furthermore, if one large video gets corrupted then you lose more data.

Record Video, Then Acquire Data

If you use the option Save video only, track later, Trial Control is not applied, so you cannot control the white light of the DanioVision Chamber with EthoVision XT.

To save video when doing tracking, follow the procedure for acquiring data live, with the difference that you select Save video only, track later in the Acquisition Settings pane. Also make sure that the trial is time limited, either with a time condition in the Trial Control start-stop rule or with a Maximum Trial Duration setting.

Next, you can acquire data using batch acquisition. Plan your trials in the Trial list and specify the video and optionally Arena Settings, Trial Control Settings, and Detection Settings for each trial.

Note: The recommended maximum trial duration when recording video is 60 minutes. Longer video recordings produce files of excessive size that are more difficult to manage. Furthermore, if one large video gets corrupted then you lose more data.

Drain and Clean the System

At the end of the experiment, we recommend removing all the water from the basin and the tubes.

If you use the Temperature Control Unit (DV-TCU), set it to Fill/Drain and follow the instructions in the relevant section of this guide.

To prevent the growth of algae in the system:

• Always drain the system after use.
• Do not expose the system and the tubes to sunlight.

Source: DanioVision DVOC-0050 Reference Manual - Acquire Data, Noldus Information Technology