JaxCC1 project protocol for procedure: light / dark

Multisystem phenotyping of 18 Collaborative Cross strains   (2018)

The Jackson Laboratory

See also: JaxCC1 animal documentation         All protocol docs for JaxCC1


See JAX Pipeline on the IMPC website for order of tasks for all mice tested

Project protocol: Light-dark box test



Introduction

The light-dark box test measures the anxiety-related behavior of mice in a two-chambered light-dark arena.



Study design

  • Paradigm: Baseline study
  • Panel: Collaborative Cross
  • Number of strains: 18
  • Sex: Both
  • Age: 8-10 wks
  • Sample size: Seven mice per sex from at least two litters
  • Number of cohorts: 1



    Workflow

    Step Description Equipment Data collected
    1 Mice are acclimated to test room for at least 3 days - -

    2

    Each mouse is placed in the light side of the arena Light-dark box -
    3 Behavior is recorded for 20 min Light-dark box Latency to enter dark zone, time mobile in each zone, time spent in each zone, percentage of time in each zone, number of transitions between zones, number of fecal boli


    Equipment, software and supplies


    Reagents and solutions

    • 1% Virkon S solution

     

    Procedure

    1. Mice are allowed to acclimate to the testing room for a minimum of 3 days.
    2. Light levels within the room are set so that the light intensity in the light arena is between 100-200 lux and 4-7 lux in the dark arena. Light metering is performed at the start of each test day.
    3. Photobeam sensor check is performed using the built-in diagnostic function at the beginning and end of every trial.
    4. Each mouse is placed in the light side of an arena.
    5. Behavior is recorded for 20 min.
    6. At the end of the 20 min test, mice are removed from the arenas and returned to their home cages.
    7. Arenas are cleaned with 1% Virkon S solution to disinfect and remove scent cues from previously tested mice.
    8. Analysis of the recording is done to measure the activity of each mouse in each of the two zones and the number of transitions between zones.

    Data collection: The Accuscan Versamax system in configured to report parameters for each mouse. Versamax files are converted into text data files using Versadat. It outputs a .DPP file containing light-dark information. Raw data is stored until outlier detection and other QA/QC procedures are complete. Local data processing is implemented to calculate derived measures from this data and a table of the derived measures and raw time per bin per zone is reported per mouse in the LIMS system.

    Data QC: Verify that total time of each run is 20 min.

    Formulas and derivations: Local data processing is implemented to calculate derived measures from these data, and a table of the derived measures and raw time per zone are reported per mouse in JaxLIMS.

     


    Measurements

    LIMS field name MPD variable name Description Units Series Primary measurement Series order MPD computed Calculation Method Data type
    Side changes transitions_LD number of transitions between light and dark zones, 20 min test n           light-dark box test Integer

    Left side time spent

    light_dur_LD time spent in light zone, 20 min test s           light-dark box test Float
    Time mobile left side time_mobile_LD time mobile in light zone, 20 min test s           light-dark box test Float
    Right side time spent dark_dur_LD time spent in dark zone, 20 min test s           light-dark box test Float
    Time spent mobile right side time_mobile_LD time mobile in dark zone, 20 min test s           light-dark box test Float
    Fecal boli defecation_LD fecal boli count, 20 min test n           light-dark box test Integer
    Reaction time reaction_time_LD latency to enter dark zone, 20 min test s           light-dark box test Float
    Percent time in dark pct_dark_LD percentage of total time in dark zone, 20 min test %           light-dark box test Float
    Percent time in light pct_light_LD percentage of total time in light zone, 20 min test %           light-dark box test Float


    Experimental and technical parameters

    Light level in light zone 100-200 lux
    Light level in dark zone 4-7 lux
    Equipment name Light-Dark Insert
    Equipment manufacturer Accuscan
    Equipment model Accuscan Versamax
    Start time 0700 - 1700 EST
    Disinfectant 1% Virkon Solution