Low cost rodent activity monitoring instrumentation

Chronic fatigue syndrome (CFS) is a condition that results in moderate to severe disability. A leading symptom of CFS is that patients report critical reductions in their levels of physical activity due to fatigue related symptoms. We have developed a rodent model, using rats, hamsters, and mice, that enables us to investigate fatigue and physiological rhythms in an integrated framework. The animal´s activity is one measure of great importance in the study of these rhythms and chronic fatigue. To monitor a free-ranging rodent´s activity we utilize two complementing methods: first, is an infra-red photo beam to detect and count turns of a running wheel, and second, is a force sensor located under the housing tub to detect general motion. Both methods are used in the animal´s home cage and are made to be low cost, compared to commercial units, for implementation on many animals