Prolonged physical restraint should be avoided unless essential to the research objectives. All physical restraint, other than routine manual restraint, must be described in the protocol. Physical restraint for periods longer than 15 minutes must be described in detail and justified for approval by the Animal Research Committee (ARC). Convenience is not justification to use prolonged physical restraint. The least restrictive method of restraint possible should be used, even though it may be more costly and technically more difficult.

When prolonged physical restraint is required, the following considerations must be addressed:

  1. Once a protocol involving prolonged physical restraint has been approved by the ARC, the animals undergoing prolonged physical restraint must be observed by a member of the Division of Laboratory Animal Medicine (DLAM) veterinary staff during the initial conduct of the experiment to ensure that the animals are not undergoing undue distress.
  2. Unless an exception has been specifically approved in the animal use protocol, animals to be placed in restraining equipment should be conditioned to the equipment by gradually increasing time of restraint until the required restraint time is reached.
  3. The period of restraint must be limited to the minimum required to accomplish the research objectives.
  4. For the comfort and safety of the animal, certain types of restraint equipment, such as slings for dogs, require that the animals be attended continuously throughout the period of restraint. For each situation, the ARC will make a determination as to the intensity of the attention required.
  5. Nonhuman primates must not be maintained in restraint devices unless required for health reasons as determined by the Attending Veterinarian or as part of a research proposal approved by the Committee. Maintenance under such restraint must be for the shortest period possible.
  6. Attention must be given to the possible development of lesions or illnesses associated with restraint, including contusions, decubital ulcers, dependent edema, and weight loss. If these or other problems occur, prompt veterinary care must be provided. If the DLAM veterinarian tending the animal considers the health problem serious, the well-being of the animal must take priority over the experimental objectives.


  1. Code of Federal Regulations, Title 9 (Animals and Animal Products), Chapter 1, Subchapter A (Animal Welfare), Part 2, Subpart C, §3.81(d).
  2. Guide for the Care and Use of Laboratory Animals. National Research Council, 2010.
  3. Guidelines for the Care and Use of Mammals in Neuroscience and Behavioral Research. National Research Council, pp. 46-49, 2003.

Approved 11/13/00; Revised 1/28/02, 5/24/04, 4/12/10; Updated 1/18/11