Institutional Animal Care and Use Committee

Policy #2011-4

“Special Monitoring Requirements” 

For protocols involving tumors, metastasis, ascites production , infection challenges, and other conditions wherein rodents may be expected to lose weight, monitoring should include utilization of the Body Condition Score (BCS)[1]; a numerical, objective scoring system for evaluating a rodents weight loss and health. Combining this method with other humane endpoints such as dyspnea, dysambulation, moribund status or evidence of unmitigated pain provides a more accurate assessment of an animal’s condition, and may prevent unnecessary pain or distress.   The Institutional Animal Care and Use Committee will review monitoring procedures (Animal Use Protocol Form questions 17 &18) for the inclusion of BCS.  An anticipated BCS of 2 (under-conditioned) or lower (range 1-5) requires scientific justification in the protocol. It is recommended that when a rodents physical condition is deteriorating, a Body Condition Score of 2 should be used as the humane endpoint, indicating the animal will be euthanized. 

See below for additional information and diagram. 

Approved: 11/16/2011 

Reviewed and Reapproved: 10/20/2015 


Ullmann-Culler & Foltz, Body Condition Scoring: A Rapid and Accurate Method for Assessing Health Status in Mice.  Lab Anim Sci, 1999,Vol.49, No.3  

[1] Body Condition Scoring of Rodents 

Description of procedure: 

Scoring the body condition of rodents is a non-invasive method for assessing health and establishing endpoints for adults where body weight alone is not a valid monitoring tool, such as with tumor models, ascites production, and pregnant, or growing animals. 

Body condition scores (BCS) range from 1 (emaciation) to 5 (obesity). An anticipated BCS of 2 (underconditioned), or lower, requires justification in the protocol. 

Scores are determined by frequent visual and hands-on examination of each animal. The hands-on evaluation is done by gently holding the mouse by the base of the tail and passing a finger over the spine and sacroiliac (pelvic) bones.  The findings are matched to the descriptions and diagrams below to determine a score.  Scores must be documented for each animal. 

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