• 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 2-4 Weeks	Estimated Exsanguination Volume
25 gm	1.875 ml	0.1875 ml	0.9375 ml

• If you are not experienced in blood collection techniques, training is available.

Collection Site	Advantages	Disadvantages
Lateral tail vein	Anesthesia not required Vein is easily accessed	Must be securely restrained Yields only small quantities Some specialized equipment needed
Orbital Sinus or Plexus	Large volumes of blood can be collected	Anesthesia is required
Lateral Saphenous Vein	Anesthesia not required Excellent technique for seaial blood sampling Moderate volume of blood can be collected	Requires some specialized training Some specialized equipment required.
Please see the following site for a demonstration in lateral saphenous blood collection from mice.
Cardiac Puncture	Maximum volume of blood can be collected	Requires deep anesthesia. Non-survival procedure only