Collecting Mouse Tail
Equipment consists of:
- Ethyl Chloride Spray.
- Sterile pot filled with 70% solution ethanol.
- Small pair of serrated forceps for tail collection.
- Small pair of sharp surgical scissors for tail snipping.
- Ear punch to identify mice.
- Small hand held cauteriser (Aaron battery operation)
- Two small containers for holding males and females from the litter.
- Kimberly Clarke tissues.
- Tail snip sheets for record keeping.
- 1.5 ml eppendorf flex tube for each tail.
- Fine point permanent marker pen.
This is the method currently employed to take tail snips from weanling mice.
The tail snip biopsy will be carried out under a local anaesthetic normally between 10-14 days of age and 0.5 cm of tail will be removed.
With adult animals (or animals over the age of 21 days) a general anaesthetic will normally be used.
At 10-14 days the pups are easier to handle and easier to restrain. The ear marking system and tail biopsy can be performed without risk of an animal bite to the technician.
Each strain of mouse is allocated a unique identification letter. This will not change and will remain with the strain throughout its duration within the unit.
Each mouse will be allocated a unique number that will remain with the mouse.
The number system commences from 1.
The founder animals will always be the initial first numbers.
- Record the parents and litter information on the tail snip sheet.
- Record the number of mice as well as sex of mice on the tail snip sheet.
- All the males will be identified first followed by the females.
- Allocate the identification number and earmark to the mice.
- The identification number will follow on from previous litter recorded.
- Allocate a flexi tube per mouse and write the strain letter and identification number of each mouse on the tube.
Set out your instruments on the workbench.
- Take the first mouse listed on your tail snip sheet.
- Place the mouse on the bench and restrain it.
- Spray the last quarter of the tail with the Ethyl Chloride spray.
- Wait a couple of seconds for the tail to turn white.
- Remove 0.5cm of the tip of the tail using the surgical scissors.
- Place the scissors into the pot of ethanol.
- Cauterise the tip of the tail to prevent blood loss.
- Place the mouse back into the cage with the parents.
- Pick up tail section using serrated forceps and place into the appropriately numbered tube for that particular mouse.
- Dip the forceps into the ethanol and wipe dry using the Kimberley tissue.
- Remove the scissors from the ethanol and wipe dry with the tissue.
- Repeat the above procedure for all pups in litter.
- When all pups have been snipped place the weaning date on the cage using a post it sticker.
For adult mice.
The adult mice will be anaesthetised using a general inhalation anaesthetic instead of the local spray anaesthetic.
The same method as described above would then apply to the tail snipping of the adult mice.