Animal Handling Crash Course (Light)

Hey Everyone !

A little procrastination here and there, but the bottom-line is...this post is up.XD And without further ado, here we go...

Basically my mp is on the Development of Type II Diabetic Mouse Models, and because of this, I’ll have to inevitably deal with mice. Initially i thought it would merely mean playing with mice quite literally, but it turned up to be that I’ll be their worst nightmare...

Since I've to deal with mice with regards to my MP, I was put through a 3hrs vet science crash course. Upon my arrival, I was immediately thrown with a stack of notes about various mice techniques which i need to know, and told to read... (Stack of notes = thickness of mmic textbk !). No further instructions, just read...so i immediately started to copy whatever's important frantically.

Then came an ex-vet science student, who gave me an odd look of bewilderment and inquired," you don’t have to copy a single thing, we are going to show you a video which will flash a list of techniques quite systemically and those techniques will be imparted technically.”


And the projector ahead started to play………………...........


Topic 1 : Proper technique of restraining a mouse


- The most basic technique of restraining a mouse is with your hands, and the technique is called scruffling.
- By using your index and thumb, grab the skin located between both shoulder blades on the back of the mouse.
- To ensure that the mouse has been firmly scruffled, the mouse's head mustn’t be able to move.
- Insert the tail of the mouse between your pinky and ring finger for double assurance.
- This scruffling techniques enables the handler to perform more sophisticated techniques such as phlebotomy and injections.



Topic 2: Sex Determination


- Gender of mice must be clearly distinguished by checking the distance of their anogenital.
- Female's anus to genital area: 0.5-2.0cm
- Male's anus to genital area : 2 – 4 cm


Topic 3: Gavaging


- Aka forceful feeding by mechanical means into the stomach
- Materials: ~ Syringe
~ Gavaging needle (Comes in different lengths)
~ Drug to be administered
~ Desired Mouse

- Select the appropriate length of gavaging needle.
- Perform the selection by picking a gavaging needle and match it against the length from the tip of the nose to the last rib. To detect the last rib, one has to personally observe and feel the chest of the mouse 1st handedly!
- Next, it's vital to check that the plunger of the syringe is working fine by simply stimulating the aspiration motion to verify its mechanical function.
- Ensure that the mouse has been firmly scruffled
- Draw the drug into the syringe.
- Insert the gavaging needle to the nozzle of the syringe.
- Gently and slowly insert the gavaging needle to the back of the throat.
- Gently slide it down in a curved motion by following the anatomy outline of the mouse's GI tract.
- If met with any resistance or if gaggling was observed, halt and gently withdraw the needle slightly. NEVER FORCE !
- Try to shift the needle either to the left or right and allow it to slide down gently until the nozzle of the syringe comes in contact with the mouth of the mouse.
- While administering the drug, always pay fullest attention the mouse’s reaction.
- Once administered, withdraw the gavaging needle with the exact motion from before, gently.
- Dispose both the gavaging needle and syringe.
- Stroke, pat and cuddle to relieve the mouse from the inflicted stress.
- Document and return the mouse back to its cage.


Topic 4: Subcutaneous Injection


- Draw the required amount of drug into the syringe and insert the needle into the nozzle.
- Scruffle the mouse firmly and usual, and this will form a superficial triangle shape at the back of its head.
- Note the base of the triangle and swab the area gently with alcohol swabs.
- Allocate the needle parallel to the triangles base, bevel up.
- Insert the needle in, do not hesitate.
- Always ASPIRATE prior to administration to check the appropriateness of the needles depth.
- Ensure that vacuum is being aspirated.
- Proceed on with administration of drug, slowly and gently.
- Once the needle has been retrieved, immediately apply pressure on the injected site to reduce loss of blood.


*Maximum Vol. for sc jab : 2ml
*Maximum Needle size : 22 gauge (Needle size increases with decreasing gauge)


Topic 5: Blood Collection from Tail


- This technique can be utilized to collect up to 200µL of blood.
- Prepare the syringe with a needle adhered. (Always prepare the necessary equipments prior to the procedure to reduce hassle.)
- Warm the tail by rubbing it gently to promote vasodilatation of the tail vein.
- Naturally, the dark blue vein will become visible.
- Place the mouse under firm restraint. Mechanical restrains are highly recommended for this technique.
- The spot to be injected should be assigned somewhere near the tip of the tail, but obviously not too near the edge. This practice is important in case the 1st injection ends in vain, which will collapse the vein near the tip of the tail. For every failed attempts, the subsequent injection should get closer to the main mouse's body.
- Before inserting the needle, ensure that the angle of the needle from the tail is approximately 5-10°.
- Gently and slowly insert the needle until blood is observed.
- Draw the desired amount of blood or switch to a collection tube to draw the blood inwards.
- Upon completion, use a gauze and apply substantial amount of pressure on the injected site to prevent excessive blood loss.
- Stroke and pat before returning the mouse back to the cage.


End of Animal Handling Crash Course.



Name: Albert Chan XD
Admin: 0604524I