is an important part of the process, as background information and history may enable the veterinarian to determine whether preexisting medical conditions were resolved. An examination of colony records and interviews with animal care staff may help pinpoint possible environmental triggers. Other causes for consideration include husbandry and handling procedures, the behavior of other animals in the room, temperature variances, noises, vibrations, and odors, as well as any specific research-related (i.e., protocol specifications) or investigator-related (i.e., disturbance of housing routine) activities.

Clinical signs should initially be examined in a relatively undisturbed animal in order to assess the animal’s natural unprovoked behavior (e.g., appearance, behavior, posture, respiratory rate and pattern). The animal showing signs of distress is then observed more closely followed by gentle handling and examination to measure body weight, body condition and temperature, heart rate, dehydration, and alertness. For some parameters, the degree of change from the normal scale is a useful evaluation indicator, the assumption being that the greater the deviation from normalcy, the greater the impact. For example, an animal may lose 5, 10, 20, or even 40 percent of its body weight, or its temperature may rise (or fall) by several degrees above (or below) normal. Clinical assessments can also be supplemented by video records of the animal in the colony room or laboratory testing environment.

A team approach during assessment is crucial. The assessment of distress and subsequent interventions should involve researchers, veterinarians, and technicians, as they are often the first to observe signs of distress in individual animals. The team should similarly collaborate to develop an intervention strategy once the assessment is completed.


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