• Too much blood collected at any one time may cause hypovolemic shock, physiological stress and even death. If smaller volumes are collected too frequently, anemia may result.
• As a general rule, 10% of the total blood volume can be collected at one time every 2-4 weeks. Or 1% at intervals of 24 hours or more. Total blood volume can be calculated as approximately 7.5% of body weight.
• The estimated volume at exsanguination is approximately half of the total blood volume.

EXAMPLE

Average Adult Weight	Total Blood Volume	Maximum Sample in mls q 2-4 Weeks	Estimated Exsanguination Volume
300 gm	22.5 ml	2.25 ml	11.25 ml

• Use aseptic technique
• To improve vasodilation effects in rodents, it is helpful to warm the entire patient. This can be accomplished in 10-15 min at 40^o C with a heat lamp or a special commercially available warming chamber. Care should be taken to prevent overheating.
• The choice of anesthetics is an important consideration when collecting blood from rodents due to physiologic effects of the anesthetic. Consult with a LARC veterinarian.
• If you are not experienced in blood collection techniques, training is recommended. If you have questions or comments about any of the above techniques, contact an LARC veterinarian @ 476-2204.

Collection Site	Advantages	Disadvantages
Lateral tail vein	Vein is easily accessed Anesthesia not required Yields moderate quantities	Specialized equipment is needed Animal must be securely restrained
Ventral Tail Artery	Large quantities of blood can be collected	Anesthesia is required Requires training
Orbital Sinus or Plexus	Large volume of blood can be collected	Anesthesia is required Requires training
Lateral Saphenous Vein	Large quantities of blood can be collected Anesthesia not required Excellent technique for serial sampling	Requires training
Anterior Vena Cava	Large quantities can be collected	Requires anesthesia Requires specialized training
Cardiac Puncture	Maximum volume of blood can be collected	Requires deep anesthesia Non survival procedure