Researchers using laboratory animals must attempt to minimize pain and distress in the animals as much as possible.
Problems:
(1) It can be difficult to determine the degree of pain experienced by an animal.
(2) Distress is usually determined by observation of animal behavior which may be neither sensitive nor specific.
General concepts:
(1) The relative pain caused by an intervention should be estimated.
(2) Distress behaviors should be judged by someone familiar with the species being studied.
(3) Observations should be performed at a time relevant to the species daily cycle (for example, rodents are often nocturnal).
Behaviors that may indicate distress:
(1) change in eating and/or weight loss
(2) change in sleeping
(3) agitation or increased aggressiveness
(4) reduced activity, lack of movement, reduce muscle tone, lethargy
(5) change in defecation and urination
(6) abnormal respirations (shallow, rapid, labored)
(7) vomiting
(8) poor grooming
(9) inattention to ongoing stimuli
(10) runny, glassy or unfocused eyes
(11) change in vocalizations
(12) change in sexuality
(13) change in sociability, withdrawal
(14) any other deviation from "normal" behavior
