Use of the Open Field Maze to Measure Locomotor and Anxiety-like Behavior in Mice

The overall goal of this procedure is to introduce the open field maze as an easy to use platform to visualize general locomotor behavior and to specifically measure anxiety related emotional behaviors. In eroded model. This is accomplished by first setting up the maze platform and camera tracking system to measure the behaviors of interest.

The second step is to introduce the mouse subject to the maze in such a way as to minimize background noise received by the camera. Next, the mouse is allowed free and uninterrupted movement throughout the maze en closure, which is captured by the camera using video tracking software. The final step is to analyze the data obtained from the tracking software to determine any differences in parameters used to measure anxiety related behaviors.

Ultimately, the open field maze can be used to measure locomotor activity and anxiety related behaviors to gain insight into emotional behavior patterns in rodent models. One of the advantages of this technique over existing methods to measure anxiety in a rodent model like the elevated plus maze, is the number of ethological and conventional parameters that can be measured during a single testing session. To prepare the experiment, obtain an open field maze or OFM.

This may consist of a single or multiple activity chamber maze. Each chamber should measure approximately 50 centimeters in length, 50 centimeters in width, and 38 centimeters in height, and should be made from high density and non-porous plastic floors of the maze should be textured for traction during ambulation and maze Walls should be smooth to inhibit climbing, leave the maze quadrants completely empty. For the purpose of this test, a single quadrant of an empty four quadrant maze will be utilized.

To demonstrate the OFM prior to use, wipe the chamber with 95%ethanol to remove any scent clues left by the previous subject mouse. Allow the ethanol to evaporate completely for five to 10 minutes before testing the mice. Set up the testing in a normally lit room with light levels, approximately 500 to 1000 lux or normal office lighting conditions, and suspend a video camera above the maze by attaching it to the ceiling to enable the camera lens to see the entire maze area.

Provide yourself enough space in the room so that you are unobservable by the test subjects in the maze. Otherwise, you may influence the mice’s behavior. Open the video tracking software and select the data acquisition tab.

Then the single subject tracking. Choose the static background option located at the bottom of the screen. Next, take a picture by clicking the photo button located at the bottom of the screen.

Select the test button located at the bottom of the screen to confirm that the background image taken above is completely removed by the tracking software. A solid white field will be shown if the background image is completely removed from the tracking image. Black shadows will appear in this field if lighting conditions change or if the maze is accidentally moved, indicating the two images do not perfectly coincide.

Remedy this error by repeating the calibration step. After confirming the background settings, configure the timing options by clicking the configuration tab. Once in the timing’s heading, use the newly opened window to enter experimental parameters.

Choose the 10 minutes tracking period in the programmed time option, and set the latency period to five seconds. Enter an acquisition time of 10 minutes for the duration of the test. Set the stop control to when programmed time is over, which will automatically turn off the camera and the tracking function of the software.

Once all timings have been set, select the close button. Set the stop control to when the programmed time is over, which will automatically turn off the camera and the tracking function of the software. Once all timings have been set, select a close button to begin the open field test.

Place home cages with mice from their housing room into the testing room. Allow the mice to acclimate to the procedure room for a minimum of 30 minutes prior to starting the test. Next, remove a single mouse from the home cage by gently grasping its tail.

And place the mouse in the middle of the OFM while concurrently activating the smart software. Record the mouse immediately as it moves throughout the maze. Allow the mouse free and uninterrupted movement throughout the maze for a single 10 minute period.

At the end of the test period, gently remove the mouse from the maze and return it to its home cage. Visually count the fecal boi pellets present in the maze and manually record the numbers for further analysis. Then remove all fecal pellets and wipe up all spots of urination.

Spray the floor and walls of the maze quadrant with 95%ethanol and wipe down with a clean paper towel. Allow the ethanol solution to completely dry prior to testing other mice. Repeat the procedure with the next mouse.

The first and arguably most important specific parameter to measure in the open field maze is total ambulatory distance, wild type, or normal C 57 black six. Mice show similar ambulatory ability to a specific knockout, C seven black six mouse strain when total distance traversed is similar between strains. Further analysis of emotional behaviors is simplified because locomotor activity is removed from the equation as total ambulatory distance between the two mouse strains with similar Figma taxes or the tendency of a subject to remain close to walls was analyzed in the wild type versus knockout mice.

Fig mota increases in the knockout mice in the outer zone, which represents a rise in anxiety levels. Knockout mice exhibited an increase in fecal bolli when compared to wild type mice. Increased number of BOI can be indicative of increased anxiety and emotionality of the subject animal.

When performing this procedure, it’s very important for the person administering the test to remain as still and quiet as possible, as any unnecessary noise or movement can influence the behavior of the subject being tested.