Thorpe, E. 2020. Alternative handling techniques to reduce anxiety in laboratory mice. Animal Technology and Welfare 19(1), 76-78.
Recent studies at Liverpool University have indicated that handling mice by their tails during routine cleaning and procedures induced aversion and high anxiety in many commonly used strains. The evidence from the Liverpool study suggests that habituating the mice to use a clear plastic tube enables the technologist to move the mice from cage to cage via the tube reducing the need to handle them which in turn lowers anxious behaviours. We decided to trial this new method to see how long it would take the mice to habituate to the tube and whether there was any visible reduction in anxiety compared to our normal tail handling method. We also wanted to assess the time impact that using this alternative method of handling would have on the duties of the animal technician. All mice underwent light/dark box exploratory test, to evaluate anxiety levels at the beginning of the experiment and 6 weeks later at the end and values compared. We used 12 adult transgenic male mice on a mixed background. Once a week at the weekly cleaning, the tube method was used on the six mice that had tubes in their cage and the other 6 mice were cleaned by the ‘normal’ tailing method. Although the results from the light/dark test comparing each group for anxiety at day one compared to 6 weeks later after the different handling techniques were not statistically significant after analysis, there is a significant reduction in anxiety (40%) in the group using the tube method. During this short trial it was noted the mice using the tube method after a few weeks were willing to enter the tube on their own accord and would quite comfortably sit in the tube whilst being transferred. We also observed, consistent with the original publication, that they preferred their own home cage tube as opposed to a clean one. We also observed that the mice being picked up by the tail remained evasive and resisted capture. By the 12th week, using the tail-handling technique took on average 10.10 s while using the tunnel method took 12.5 s. In summary, the overall reduction in observed anxiety in the tube group combined with the bio containment benefits it offers makes this method worth considering or exploring further given that we found the difference in time taken for each method was negligible when cleaning out mice.