Open Field Task

The open field test is a commonly used test to assay anxiety-like, exploratory, and locomotor behaviour in mice. It is based on the idea that mice do not like spending time in bright exposed places, and prefer dark corners or edges.

Materials

To run this test you will need the following equipment:

• 1-4 Open Field Box: 45 x 45 cm2 rectangular light grey arena (dimensions for mouse, rat boxes are larger)
• Camera, pole, and recording equipment

Methods

• At least 30 minutes before you plan to start your behavioural test, bring your mice to the behavioural room and allow them to habituate in the ante-chamber
• While your mice habituate, set up your camera and open field boxes so that the camera is placed directly above your boxes. You can record up to 4 boxes at a time.
• Ensure that the room light is on, and brightly shining over the boxes, and that you do not have any noticeable shadows over your boxes (this may affect the regions in which mice spend their time exploring).
• Once the equipment is set up and your mice are habituated, you may start the test.
• Bring the mice you plan to test into the behavioural room, and gently holding them at the base of the tail, and supporting them on your forearm, place them in the center of the open field box. Repeat this if you are testing more than one mouse at a time
• Exit the room and begin recording for a total of 15 minutes
• Following the end of the recording, return the mice to their home cage, and thoroughly clean the boxes with peroxiguard.
• Repeat as needed.
• Make sure to back up your recordings to the CIC server after you are done recording to prevent any data loss.

** NOTE: it is best to test male and female mice separately, as the smell of the opposite say may confound their behaviour.

** Additional reading: https://www.noldus.com/blog/behavioral-testing-improve-your-open-field-test