This Page includes general practices that should be followed for optimal behavior data collection conditions. These practices should be applied, where appropriate, to all behavioral tasks.
- Number of mice in a cage: No more than 5 mice should be housed per cage. Previous research suggests that for male mice, limiting cages to three males creates an ideal social home cage situation.
- House by experimental group: Data from our lab and others (REFS) suggests that the behavior of control animals can be influenced by the presence of the experimental group animals, and vice versa. Therefore, it is ideal to house by sex and by experimental condition.
- Avoid isolation housing: Avoid isolation housing at all times unless it is specific to your experimental treatment. Mice and rats are social creatures and isolation housing, even for as short as a week, has been shown to alter baseline behaviors and decrease weight.
- If your experimental condition cannot be decoupled from litter (e.g. if you are exposing dams to drug), cull your litters to the same number of pups to control for the chance of equal maternal care.
- Always design your study with the most stressful tasks at the end to minimize effects on other tasks. This is a very important consideration for behavioral testing.
Setup for Behavioral Tests
- Read over the protocol for your task before starting testing each day (even if you’ve run it 100 times before, something may be missed)! Have one printed out that you keep with you as you conduct your assay and save in the study folder for reference on what procedure was used when writing the manuscript.
- Set up apparatuses and tracking (ANY-maze or Ethovision) at least 1 day prior to start of testing.
- After completion of setup, run extra mice with coat colors matching your experimental mice in each apparatus the day before testing to ensure tracking is optimal.
Running Behavioral Tests
- Acclimate animals to handling: Handle animals at least 3 days prior to the start of testing. This will acclimate the animals to handling and decrease the influence of handling stress on performance. Handling should be done by the experimenter that will be conducting testing
- Consistency: Behavioral testing should be conducted at approximately the same time each day, and during the same phase of the light/dark cycle.
- Temporal effects: Choose the most appropriate time of day for the test you are conducting. Mice are more active later in the day, closer to the dark cycle (their active period). Thus, some cognitive tasks and social tasks are more appropriate to run in the afternoons. Tasks that require the mice to be as chill as possible, like VOS or von Frey, should be run early in the morning.
- Keep males and females separate: Separate males and females during testing as much as possible. Run males in an apparatus first, even on a different day if necessary, as appropriate for your experimental design and hypotheses being tested. Keep male and female cages separated in the acclimation or testing room.
- Avoid strong perfumes/cologne: Rodents are especially sensitive to odorants and some smells that are neutral to humans may be aversive to them. Animals also become acclimated to the scent of the experimenter. As you can, keep your clothing detergents, deodorant, body lotions, etc. constant during behavioral testing within a study. If possible, minimize any scented products during behavioral testing.
- Minimize noise: Noise should be eliminated as possible during behavioral testing, including talking. This can startle animals during testing and disrupt data collection. Music should never be played aloud during testing unless it is part of your experimental condition.
- Transfer files to the Box or your lab’s cloud storage of choice at the end of each test day. THIS IS IMPORTANT. If the computer dies, we lose data if it is not transferred.
- Clean up immediately after you finish your experiment. Be a good steward of shared equipment and shared procedure spaces.
- Rats are predators of mice, so they should never occupy the same space together. If you need to run rats and mice in the same day, run the mice FIRST, then run the rats (do not even enter the rat colony room before finishing the mice). Then, change your lab coat between species.