The Center for Alternatives to Animal Testing is an academic center affiliated with the Division of Toxicological Sciences in the Department of Environmental Health Sciences of the Johns Hopkins University Bloomberg School of Public Health.

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Research Grants 2002-2003

Differential Effects of Environmental Enrichment for Mice

Hal Markowitz, PhD and Clifford Roberts, DVM
University of California, San Francisco, California

Perhaps the most important refinement that can be made in the use of living animals in biomedical research is to improve the ways in which they "model" the disorders for which we seek cures. In this research we evaluate the effect of a number of different daily living conditions and exercise regimen for mice on their behavior and disease progress. Mice that are models for familial Amyotrophic Lateral Sclerosis (ALS) will be assigned to four groups: traditional caging; cages with "mouse houses"; cages with exercise wheels; and a group with wheels in their home cages and individual exercise regimen involving training six days a weeks. Control animals of the same strain will be assigned to identical groups.

Using standardized tasks to evaluate the behavioral abilities of the experimental animals as their disease progresses we will assess the utility of these different living conditions in slowing or accelerating progress of the functional disorder. Examples of these tests, which closely mirror the tests made on human ALS patients, include ability to balance on a rotating rod, gait analysis, and monitoring of food consumption. The control animals will be used to compare these results with normal behavioral change associated with increased age. Differences as a function of caging conditions are not often properly considered and seldom used as a critical component of experimental design. If our results do show differential outcomes we anticipate that methods similar to these will be used increasingly by researchers to refine their use of experimental animals.