4 top methods of blood collection in lab rodents

The methods of blood collection in lab mice and rodents can have varying effects on the animals. The sample collection methods may require anesthesia or restraint, depending on the area from which the blood is taken. Certain areas produce more blood during collection, and guidelines prescribe the total amount of blood that can be drawn from a mouse or rodent via each method.

With all animal studies, it is important to use the least invasive sampling methods available to minimize impact on the animals, while still obtaining the data necessary for scientific analysis. 

Here we describe the top four methods of blood collection in lab mice and rodents.

1. Venous blood draws from the lateral tail vein or the submandibular vein

Are usually taken while a mouse or rodent is restrained but not anesthetized. Both of these methods require special equipment, and a lateral tail vein draw yields only a small quantity of blood. The submandibular vein is preferred because it's ideal for serial sampling and can draw a moderate amount of blood.

2. Saphenous or retro-orbital vein collection 

Is another way. Both of these collection sites require additional preparation and skill. Extraction from the saphenous vein requires great skill to consistently draw a measurable amount of blood.

Because of the extensive site preparation, the mouse might be more traumatized with this method due to prolonged restraint. The retro-orbital vein can provide medium or large volumes of blood, but the mouse must be monitored within two days after blood collection because complications can happen.

3. So-called "terminal" or "non-survival" blood collection

Is done either pre- or post-mortem and only after the mouse has received surgical anesthesia. Terminal collection can be taken via cardiac puncture and can collect the maximum amount of blood. It can also be done via the aorta or vena cava. Immediately after the blood collection via either of these two methods—and before the mouse recovers from the anesthesia—the mouse must be euthanized.

4. Microsampling: the 3R blood collection method

With microsampling, a very small volume of blood is taken after the mouse or rodent receives local anesthesia. Volumetric absorptive microsampling technology enables consistent and accurate blood volume collection (roughly 10 microlitres). Because this is a small-volume blood collection approach, a single animal can be sampled from more frequently with less impact on their health.

Mitra^® devices based on VAMS^® technology provide high-quality and quantitative data while simplifying the blood collection process and the lab procedures required for testing.

The hydrophilic VAMS tips on the Mitra sampling devices fill after 2-5 seconds of contact with a small amount of blood. This simplifies the sampling method and standardizes the sample volume.

Some lab researchers have reported that microsampling is not the preferred extraction method when taking samples from rodents that have tumors or when technical replicates are required. 

Learn more about microsampling for animal studies by visiting our Preclinical Research / Animal Studies resource page: