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UNIVERSITY OF SOUTHERN MAINE
Office of Research Integrity & Outreach
Procedure #:
Date Adopted:
Last Updated:
Prepared By:
Reviewed By:
Procedure Title:
03-006
7/28/2003
12/17/2011
Sarah Gilliam, Animal Facilities Manager
USM IACUC Committee
Rodent Blood Collection Procedures
1.0 Purpose: To make sure that proper technique is used to obtain a blood sample from
the animal to avoid and/or limit pain and distress to that animal.
2.0 Responsibility:
2.1 It is the responsibility of the investigator, technician, or student performing
the task to follow the procedures outlined in this document.
3.0 Applicable Documents:
3.1 SOP 03-003 Mouse Procedures
3.2 SOP 03-004 Rat Procedures
4.0 Mouse Procedures:
4.1 Total blood volume for a mouse is 1.6-3.2ml, with a single sample usually
being 0.2-0.3ml.
4.1.1.1 Mice cannot be bled more than once a week, unless
approved by IACUC.
4.1.1.2 Mice should be rechecked later in the day for signs of
dehydration or distress.
4.2 Mandibular Bleed:
4.2.1 This is the preferred method for blood collection in mice at
USM. The use of any other method in mice should be justified to
the IACUC.
4.2.2 Animal should be properly restrained and anesthetized if necessary
prior to procedure.
4.2.2.1 Choose the appropriate lancet for the age of the mouse.
Use a 5 mm point for ages 2-6 months or 5.5 mm point for
over 6 months old.
4.2.2.2 Prepare the lancet and collection tube for bleeding so that
they will be close by, but in a way that does not allow the
sterile tip of the lancet to be contaminated.
4.2.2.3 Restrain the animal in accordance to SOP 03-003 Mouse
Procedures.
4.2.2.4 Locate the back of the jaw bone where there is a vascular
bundle from which to collect blood.
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4.2.2.5 Once the correct location is found, use the lancet to quickly
puncture the area (no deeper than the lancet point) and
withdraw the lancet. Dispose of the lancet in a sharps
waste container.
4.2.2.6 As the blood appears from the puncture, use the collection
tube to harvest it, being careful not to exceed the
recommended 10-15% of total blood volume or 1% of body
weight.
4.2.2.7 Once the sample is collected, use gauze to press against the
site in order to stop the bleeding.
4.2.2.8 Place the mouse back in its cage and observe until fully
recovered from the anesthesia (if used). Note on the cage
card the date of the procedure.
4.3 Retro-orbital Bleed:
4.3.1 Animal should be properly restrained and anesthetized.
4.3.1.1 Make sure to clean the anesthesia chamber before & after
each use as well as between animals to prevent the spread
of pathogens.
4.3.1.2 Insert the end of a micro-hematocrit tube into the retroorbital sinus via the medial canthus.
4.3.1.3 After the tube is full, either place into a sample tube or
insert the tube into sealing compound.
4.3.1.4 Label the sealing compound or sample tube with the animal
information and date.
4.3.1.5 Do not collect more than 3 tubes per mouse, unless
previously approved by IACUC.
4.3.1.6 After collection, gently wipe area with clean gauze &
observe for additional bleeding.
4.3.1.6.1 If bleeding continues use clean gauze to apply
gentle pressure to the area until the bleeding
stops.
4.3.1.7 Note on the cage card the date and the procedure done.
4.4 Tail Bleed:
4.4.1 A 26-28 gauge needle should be used.
4.4.2 Animal should be properly anesthetized or restrained (in a rodent
restrainer).
4.4.3 Either the ventral caudal artery or the lateral caudal veins may be
used for collecting very small amounts of blood.
4.4.4 Warming the animal’s tail by placing it into a cup of warm water
can be done to improve circulation within the tail.
4.4.4.1 Be sure to test the temperature of the water, if it is too hot
for the technician then it is too hot for the animal.
4.4.5 Disinfect the site with an appropriate disinfectant.
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4.4.6
4.4.7
Insert the needle, bevel side facing up, into the artery or vein &
collect the blood from the hub of the needle with a sample tube.
After removing the needle, apply gentle pressure to the vessel
using clean gauze to stop the bleeding.
4.5 Cardiac Puncture:
4.5.1 This is a terminal procedure.
4.5.2 Use a 22 gauge needle.
4.5.3 Animal should be properly anesthetized or euthanized prior to
procedure.
4.5.3.1 Be sure to clean the anesthesia chamber before & after each
use as well as between animals to prevent the spread of
pathogens.
4.5.4 Two methods:
4.5.4.1 First method is to insert through the intercostal space
(between the ribs) on the left side at the PMI (Point of
Maximum Intensity) of the heart beat.
4.5.4.2 Second method is to place the animal in dorsal recumbency
and insert the needle through the diaphragm below the
xiphoid cartilage.
4.5.4.2.1 Then direct the needle toward the PMI.
5.0 Rat Procedures:
5.1 Total blood volume for a rat is 20-40mls, with a single sample normally
being 2-3mls.
5.2 Mandibular bleed:
5.2.1
This is the preferred method for blood collection in rats at
USM. The use of any other method in mice should be justified to
the IACUC.
5.2.2 Animal should be properly restrained and anesthetized prior to
procedure.
5.2.2.1 Choose the appropriate lancet for the age of the rat. Use a
5.5-6 mm point for ages 8-12 weeks, 6-7 mm point for 1216 weeks, and a 7-8mm point for any that are over 20
weeks of age.
5.2.2.2 Prepare the lancet and collection tube for bleeding so that
they will be close by, but in a way that does not allow the
sterile tip of the lancet to be contaminated.
5.2.2.3 Restrain the animal in accordance to SOP 03-004 Rat
Procedures.
5.2.2.4 Locate the back of the jaw bone where there is a vascular
bundle from which to collect blood.
5.2.2.5 Once the correct location is found, use the lancet to quickly
puncture the area (no deeper than the lancet point) and
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withdraw the lancet. Dispose of the lancet in a sharps
waste container.
5.2.2.6 As the blood appears from the puncture, use the collection
tube to harvest it, being careful not to exceed the
recommended 10-15% of total blood volume or 1% of body
weight.
5.2.2.7 Once the sample is collected, use gauze to press against the
site in order to stop the bleeding.
5.2.2.8 Place the rat back in its cage and observe until fully
recovered from the anesthesia. Note on the cage card the
date of the procedure.
5.3 Tail Bleed:
5.3.1 Normally bled from the lateral tail vein.
5.3.2 Use a 25g needle.
5.3.3 Follow steps 4.2.2 through 4.2.7 in Section 4.0 Mouse Procedures.
5.4 Cardiac Puncture:
5.4.1 This is a terminal procedure.
5.4.2 Follow steps 4.4.2 through 4.4.4 in Section 4.0 Mouse Procedures.
03-006