Handling and restraint in the mouse

Almost all laboratory animals can be restrained safely and humanely provided they are handled correctly. All animals benefit from being first accustomed to being handled, and this can be done during the period of acclimatisation needed before they are used in a research procedure.

Key points to note

It has been shown that picking up mice by the tail induces aversion and high levels of anxiety. (Hurst & West 2010¹)

Using tunnels or cupping the mice in open hands leads to the more rapid acceptance of physical restraint. Habituation to this type of initial restraint persists even when mice are subsequently restrained more securely, for example by the scruff to allow injections to be carried out. There are many resources available on handling laboratory mice on the UK NC3Rs website (nc3rs.org.uk/how-to-pick-up-a-mouse).

If injections are to be repeated on a regular basis, then familiarisation with restraint assumes even greater importance, and training of the animal to co-operate with the procedure may also be helpful.

Restraint will be stressful, even in animals that have become accustomed to handling, so the duration of restraint should be minimised.

If you are relatively inexperienced in the technique that you plan to use, you should ensure you have an experienced assistant who can restrain the animal safely and humanely, and assist and supervise the procedure.

When carrying out procedures, make sure you are wearing appropriate protective clothing, both to protect yourself from hazards such as allergens, and to protect the animal from the inadvertent transfer of potentially infectious agents.

1. J Hurst & R West (2010) Taming anxiety in laboratory mice. Nature Methods 7 (10), 825-842