Blood Withdrawal

Blood Withdrawal

Approved November 19, 1998   (Download) 

Background: Obtaining blood samples from laboratory animals is a commonly performed procedure. A variety of techniques are used depending on factors such as the species and the amount of blood required. Policy concerning obtaining blood in rats and mice by orbital bleeding is covered separately. Concerns related to obtaining blood samples relate primarily to the possibility that excessive frequency and volume of blood withdrawals could directly affect animal health and well being.

 

Policy: Blood samples may be obtained by experienced personnel without anesthesia by venipuncture in such species as cats, dogs, rabbits, pigs, and sheep and other animals where it is possible and routine to do so easily, safely, and with minimal restraint. Bleeding procedures likely to pose safety or injury risks, such as bleeding nonhuman primates, should be performed with appropriate anesthesia or chemical restraint. Alternatively, in nonhuman primates if repeated bleeding over long periods of time is required, consideration should be given to training animals to present their rear limbs for venipuncture to reduce fear and the risk of injury. An animal may be bled out completely if done as a terminal procedure under general anesthesia. In non terminal procedures, unless scientifically justified or waived by the ACC on a case by case basis, the amount of blood withdrawn from any animal in a two week period of time must not exceed one percent of the total body weight. For example, the maximum amount of blood that can be withdrawn from a 5 kg. rabbit in a two week period is 50 ml. Exceptions to this policy may be allowed if appropriate provisions are made to monitor and maintain hematologic values within normal limits by returning red cells following bleeding, providing fluids and plasma expanders, and assuring that packed cell volume, red counts, and serum protein levels do not fall.