How to conduct refined mouse handling

Traditionally, mice are picked up by the base of the tail to be moved for cage change, exams, or procedures. Now, evidence shows that picking mice up with tunnels, huts or cupped hands is an important, impactful 3Rs refinement.

When to use tunnel handling vs. cupping?

Tunnel Handling: Requires equipment, but minimal habituation is required. Best for less experienced handlers, wild/jumpy/aggressive mice, naïve mice, or biosecurity concerns.

Cupping: No additional equipment is required, but habituation is essential. Best for more experienced handlers, outbred or older mice, habituated mice, pups and young weanlings, mice with delicate implants, and large mice that can’t fit in tunnels.

Hut handling: Requires equipment (mouse hut/shelter), which may already be present in cages as environmental enrichment in some facilities.  Hut handling is well-suited for handlers of all experience levels, as well as for use with jumpy, aggressive, or naïve mice, and in situations with biosecurity concerns.   

  • Compared to tunnels, the open design of an upturned hut leaves mice more exposed, potentially increasing the chance of escape in more jumpy mice.  
  • Some facilities may already use huts in their mouse cages, offering the added benefit of requiring no new equipment and being familiar to the mice.   

 

*Different strains may also be better suited for tunnel handling vs. cupping vs. hut handling.

How to Tunnel Handle

  1. Hold the tunnel by the middle and place it by the cage wall.
  2. Encourage the mouse into the tunnel with your hand while keeping the other end open. (Transfer the mouse)
  3. Allow the mouse to walk out of the tunnel or gently tip the tunnel backwards so that the mouse slides out.

These videos from University of Liverpool show how to use a tunnel or cupped hands to pick up mice prior to conducting normal procedures (e.g., restraint, injection).

What Not to Do:

  • Do not chase the mouse with the tunnel.
  • Do not hold the tunnel in the middle of the cage.
  • Do not share tunnels between male and female mice.
  • For wild or jumpy mice, do not leave the end uncovered, when lifting the tunnel.
  • MAYBE don’t cover the end of the tunnel in the cage. Some mice won’t enter a tunnel whose end is covered– be aware of this if the mice seem resistant to entering the tunnel.

How to Cup Handle

  1. Practice the movements in an empty cage 5x before starting
  2. Remove any enrichments to make handling easier
  3. Key principals: avoid fast/jerky movements and approaching the mouse from above. Instead keep movements smooth and confident.
  4. If tunnels are available, first tunnel handle the mouse and tip the mouse from the tunnel into your hand
  5. Approach the mouse at an angle and guide them to a wall or corner. For naïve mice, use two hands for close-handed cupping. For experienced mice, use one or two hands for open-handed cupping
  6. Scoop the mouse into your hands
  7. Move the mouse to the new location either with fully closed or open hands
  8. Set the mouse down and let them walk away.

How to Hut Handle

  1. In one hand, hold the edge of the upturned hut and place it against a cage wall or corner.   
  2. Using your other hand, gently guide the mouse into the hut and lift the hut above the cage. To minimize the risk of escape, cover the entrances of the hut with both hands.  
  3. Transfer the mouse to a new location and lay the hut on the cage floor to let the mouse walk off the hut.  
  4. If the mouse does not exit on their own, gently tilt the hut to its side to let the mouse slide out onto the cage floor. Typically, mice will choose to walk off the hut within a few seconds.  

 

*Additional considerations when hut handling jumpy mice:  Once the mouse is in the hut, you may use one hand to gently cover the top (exposed part) of the hut.  

What Not to Do:

  • Do not chase the mouse with the hut.
  • Do not hold the hut in the middle of the cage.
  • Do not share huts between male and female mice.
  • Do not leave the entrances of the upturned hut uncovered when lifting.  

Need more training?

For more detailed instructions please see NC3Rs Mouse Handling Video Clips.

or their full mouse handling tutorial.