Hi Simon,

My company has a lot of experience with mandibular bleeding – a good method to get medium to higher amounts of blood (300 to 500µl are no problem at all); No anaesthesia is needed! Please find below a publication as well as a very instructive video.

http://ddr.nal.usda.gov/bitstream/10113/41088/1/IND43787677.pdf

http://www.medipoint.com/html/directions_for_use1.html

Good luck

Birgit

I've used submandibular bleeds to longtitudinally collect samples from mice over the course of several months. I was only taking 2-3 drops (probably around 150uL) at a time and was generally only bleeding the mice once a month so there was a ~4 week interval between samplings. I collected 4-6 samples per mouse overall.

As long as the submandibular puncture was performed cleanly, I didn't generally see any ill effects over the entire 6 month period. With the 4-week spacing of the bleeds the hematocrit seemed to recovered quite well. The only problem was that a few mice occasionally developed scar tissue and/or localized dermatitis on the cheek. I think this probably only occurred when I didn't perform the bleed well and needed to do multiple punctures to get blood, because as I got more proficient at the technique this seemed to become less of an issue.

I generally used lancets for for the bleeds, but after talking to some of our vets I believe that using needles may be better. The technique is a little trickier to learn, but can be cleaner and give you less peripheral tissue damage.

Hope that helps.

i prefer Ocular bleeding, submandibular method is also good but not all the time.goodluck

Have done various types of bleeding in mice. The submandibular bleeding is one of the easiest. The key is to use the goldenrod lancet, use the smallest size and follow the video they have. It is just as easy as it shows and no anesthesia. I am quite proficient in the ocular bleeding, but the the lancet method better for the animals. It is also wise to wipe them down with alcohol swabs. It works well in rats too.

Thanks for the replies everyone.

I have been trying to profile a time-locked event, so i have been taking one sample every hour from the same animal. I was noticing that some animals did not respond well and one even died after 3 samples (1 hour apart).

Maybe this technique isn't good for sampling with such a short delay period?

what strain do u use? Some strains have a lower volume of blood compared to others.

I don't think submanidular bleeding gives you enough control for drawing blood with that kind of frequency. For drawing blood every hour I think your best option is cannulation of the tail vein. I've used this technique to do a short-term time course of nanoparticle distribution in circulating blood cells (1 sampling/hour, 20uL/sample, 4 samples in total).

Here's a website with more information on the technique:

http://www.nc3rs.org.uk/bloodsamplingmicrosite/page.asp?id=338

agrees with Adeeb Rahman

For any type of blood collection, number of blood sampling depends on the total amount you can collect from the animal. Volume of each collection depends on your technique and control. each drop of blood is approximatively 50uL. the health of the mouse will depend on the amount of blood lost.

here are some basic guidance for mouse bleeding

The consideration for blood collection from mouse:

1) Amount of blood required vs maximum amount of blood from the mouse

2) Do want the animal to live after the procedure? is it okay for the animal to be temporarily anemic ?

Total amount of blood is approximately 6% of mouse body weight (some will argue that it’s 8% or 10%). Mice that are sickly will have lesser blood content. From this amount, the maximum that can be collected is around 2/3 (4% of body weight). At maximum collection, the mouse will die due to blood loss.

The maximum amount that can be collected while leaving the animal alive is 1/3 of the maximum (2% of body weight). However this will leave the animal anemic. It takes 2 weeks to replenish the blood lost. Thus, you can only repeat the procedure after 2 weeks.

Simple maths:

Mouse weight: 20g

Max blood in body: 1.2 – 1.6

Max blood collectable (at terminal/ killing the animal): 0.8ml – 1.0ml (NOTE: no recollection, animal dies. Best method: cardiac puncture/ Retro-orbital r bleeding)

Max blood collectable (leaving mouse temporarily anemic): 0.4ml – 0.5ml (NOTE: can only recollect after 2weeks. Best method: Retro-orbital bleeding / submanidular bleeding)

For frequent bleeding (without putting the animal into anemic stress):

1) once a week: not more than 0.2ml/ per collection

2) daily: not more than 0.05ml/ per collection

3) hourly: do your maths depending on how long u want the animal to live and if the anemic stress will affect your desired results. Cannulation is best here because you don’t have much control in other collection methods. Once you have obtained a max of 0.5ml, you need to wait for 2weeks for consequent collection, unless you don’t mind killing the animal.

IMPORTANT POINT THAT MANY PEOPLE FORGET: THE TOTAL BLOOD THAT CAN BE COLLECTED, INCLUDES THE BLOOD WASTED ON THE GAUZE/COTTON BALL WHILE STOPPING THE BLEED. If anesthesia is given as IV, the blood lost while stopping the tail vein blood will reduce the amount of blood you can collect.