Blood Collection in the Pet Mouse
By Dr. Jennifer Martin
Before collecting blood from a mouse, you will need to determine the amount of blood that can be safely collected from your patient and know the frequency in which the blood needs to be collected.
If a single blood sample is needed, the rule of thumb is up to 10 percent of the total blood volume of the mouse may be safely collected every two to four weeks. Up to 7.5 percent of the total blood volume may be collected every 7 days, and up to 1 percent of the total blood volume may be collected daily.
The total blood volume of a mouse is between 77-80 ml/kg of body weight (bwt).
Here is an example:
A mouse weighs 25 grams and a single sample of blood is needed.
Recall that up to 10 percent of the mouse’s total blood volume may be safely collected as a single sample.
First, convert the weight of the mouse to kilograms. There are 1000 grams in one kilogram, so the mouse weighs 0.025 kg.
Body weight of mouse (kg bwt) = 25 g bwt x 1 kg/1000 g = 0.025 kg bwt
Next, multiply the body weight in kilograms by the total blood volume (77-80 ml/kg) to determine the total blood volume of the mouse.
Total blood volume of the mouse (ml) =
0.025 kg bwt x 77 ml-80 ml/kg of total blood volume = 1.925 ml – 2.0 ml
We are limited to collecting no more that 10 percent of the total blood volume of the mouse in a single sample collection. This is calculated by multiplying the total blood volume by 10 percent.
Maximum volume of blood that may be collected (ml) =
1.925 ml – 2.0 ml x 10 percent = 0.1925 ml – 0.2 ml
Therefore, the amount of blood that may be safely collected from a 25-gram mouse every 2-4 weeks is between 0.1925 ml – 0.2 ml.
Blood may be collected from the saphenous vein or dorsal pedal vein without anesthesia. Anesthesia is necessary when collecting blood from the lateral tail vein, dorsal tail artery, or jugular vein. Following blood collection, always monitor the mouse for signs of distress.
Jennifer Martin, DVM, CFD is the Director of the Colby Community College Veterinary Technician Program in Colby, Kansas.