Assessment of the welfare of laboratory animals is critically important. Welfare assessments are both objective and subjective and can be based on performance measures, prohibited practices, input-based standards, the Five Freedoms, record-based standards, and subjective evaluations. Whatever measure is used should have specific criteria that can be defined and quantified. While assessments using objective measures, such as cage size or numbers of live births, are the easiest to determine, these standards are not necessarily the most meaningful for the animals. Prohibited practices like rough handling can be relatively easily defined and are important to have in place for researchers or staff members who are not familiar with animal handling. Performance standards that are based on criteria indicating how the individual animal or group of animals is responding via measures of health, behavior, and physiology are the most difficult to establish but of the most overall value. 2013 Elsevier Inc. All rights reserved.
