Mice serum - (Nov/16/2006 )

Dear Tertu,

I am new to this field but have learnt this from my seniors and also read in one very old book in the library.

We do anesthetise mice before doing the procedure. We have been collecting in average 500ul of blood and the mice are healthy and our experiment requires us to collect blood in every two weeks. Mice are healthy.

Once you master the procedure, you may be able to collect without anesthesia but it is better to use some; but I have lost one mouse once and my senior said it was due to bad technique and vagal shock. Now I am fairly comfortable with the procedure and have never used any other method to collect blood. The ease with which my tutor collects blood impresses me very much. I am still not able to be like that.

too much blood collection over time may make the mice anemic (I just learned this myself) this applies to multiple collections over time

we do not anesthetize. we are very very quick.

Thanks all!.
I am not very comfortable with retroorbital, but for now I am doing a small cut in the middle part of the tail after exposing it to that red warm light. is working for me. After the cut I collect the blood with a tip and get around 100 ul. after centrifugation i can get 40 to 50 ul of serum, enough for my determinations.
Maybe later I will learn the retroorbital bleeding.


Thanks again!

You can also try this:
http://www.uib.no/vivariet/mou_blood/Blood_coll_mice_.html

Blood collection using the saphenous vein:
An alternative to retro-orbital collection


It's very useful if you have to extract more than three times because you don't render the mice blind.

Best regards,
CArla

Another option to tail vein bleeding, retro-orbital bleeding, and saphenous vein bleeding is sub-mandibular bleeding. Bleeding from the sub-mandibular is very fast and you may alternate sides every week (like retro-orbital, no need to anesthetize).

I do tail vein bleeding (collect 60-100 uL) every week and the tail is fine. I do not lance the tail, just insert needle (as though you are doing a tail vein injection) and take the needle out. This way, there is not any damage to the tail, like lancing causes.

For the amount of blood, always be sure that you are in compliance with your IACUC. 500 uL will have to be approved to withdraw so much--since the regulations are no more than 1% within a two week period.

in fact, it's 10% of total blood volume (or 1% of body weight) that can be collected every two weeks.....

mike

is that international? are the legal limits the same everywhere? I know that 1% of the body wieght is how we calculate it; however I can tell you that 200ul from a mouse is an awful lot of blood and can be very hard on the animal, even though it falls within legal limits. I suspect there may be variability between countries and/or institutions; I would contact my animal health people if I were you to determine the precise limits.

It is different for each country, I also know there differences between institutes and universities.
Also, the mice I'm bleeding are very hard to bleed. If I have a good day and the mouse to I get 100 ul, but usually it's less. (And it takes me about 10 min per mouse!! Shock!)
So it also depends on what mouse strain your using..

Our lab can routinely take 500uL PB by lancing the tail vein or retrorbital eye bleeds for viral or Ab titers in the serum. This is in B6 (and/or B10) mice that are either naive or infected with different viruses. These mice survive, and upon clearance of the pathogen are perfectly healthy.

In fact, one researcher in our group bled mice (tail vein) every 3-4 days for 2 weeks collecting no more than 500uL. This protocol was IRB approved. The mice were not very happy, but I believe that they all survived until sacrifice at 2 weeks.