Knowledge Base

Acquiring Data

Protocol

A typical open field test is carried out in the following way:

1. Transport the subject to the testing room at least 1 hr. prior to testing, to allow them to acclimate to the experimental room. This time period should be extended if the transfer involves excessive changes in the environment.
2. Clean the open field, even if it is not dirty prior to the initial trial. This way all animals experience the residual smell of the disinfectant equally.
3. In EthoVision XT, click the Start Trial button. EthoVision XT waits until the subject is detected in the arena.
4. Place the subject in the open field. Commonly, the subject is placed in the center. However, placing adjacent to a wall is sometimes used to avoid immediate exposure to a stressful situation. Also, in case of a large open field, the position adjacent to the wall may be easier to reach.
5. The researcher should leave the room, or position himself or herself as far as possible away from the arena and field of view of the subject. Also the tester should remain quiet throughout each trial.
6. Tracking starts after the subject is detected in the arena. Make sure that tracking does not start because your arm is detected instead of the animal. To do so, for example, make a door in the open field, or increase the period that the subject needs to be detected before tracking starts. If you use multiple arenas, tracking starts in each arena separately, depending on when the subject is detected in that arena. The subject is allowed to explore freely for a standardized time. Traditionally track duration was between 2 and 10 minutes, but video tracking with EthoVision XT allows longer tracking.
7. After the test has ended, take the subject out of the arena and put it back in its home cage.
8. Optionally, count the fecal boli in each zone of the open field.
9. Clean the open field and allow it to fully dry prior to introducing the next test subject.

Notes

• Tip: When tracking white animals, wear dark clothes, and when tracking dark animals, wear white clothes. This prevents EthoVision XT from detecting your arms while you release the animals in the arena.

Score Behaviors Manually

Once you have defined your behaviors of interest in the Manual Scoring Settings, you can score those behaviors in two ways:

• Live: That is, during the test. On the Acquisition screen, click the Manual Scoring tab and score behaviors when these occur.
• Offline: If you have recorded video, choose Acquisition > Manual Scoring. Review the video and add or edit behavior scores.

For more information, see Acquire Data > Score Behaviors Manually in the EthoVision XT Help.

Source: EthoVision XT 18 - Application Manual, Noldus Information Technology