Change in locomotor activity pattern in mice: a model for recognition of distress?
Recognition and assessment of pain and distress is made by observing common clinical and behavioural signs. Observation usually occurs during a limited period of time and results can be biased by interpretation of an individual observer. To improve objective assessment of distress we studied the locomotor activity pattern of mice during a 24-h interval. As a reference compound, Freund's complete adjuvant (FCA) was used. Mice were injected intraperitoneally with different doses FCA (0, 0.1, 0.2 and 0.5 ml) and observed for 5 to 7 days. Animals did not appear to be in pain and seemed to have a normal activity and behaviour pattern at first sight, however FCA induced a dose-dependent decrease of body weight. Open field activity (total distance run) measured during a limited period of time was not altered as a result of FCA. However, nocturnal activity was dose dependently decreased during the first 3 to 4 nights after treatment with FCA. The data presented indicate that using locomotor activity patterns over 24 h might be a useful adjunct and an objective approach to assess distress.
Jansen van't Land
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Central Animal Laboratory, National Institute of Public Health and Environmental Protection, Bilthoven, The Netherlands.
Hendriksen
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CF
D000818:Animals; D001835:Body Weight; D005106:Exploratory Behavior; D005260:Female; D005620:Freund's Adjuvant / Q000009:adverse effects*; D007274:Injections, Intraperitoneal; D051379:Mice / Q000523:psychology; D009043:Motor Activity; D010146:Pain / Q000175:diagnosis / Q000662:veterinary*; D012376:Rodent Diseases / Q000175:diagnosis*; D013312:Stress, Physiological / Q000175:diagnosis* / Q000662:veterinary*
D005620:Freund's Adjuvant