Welfare Assessment of Female BALB/c Mice Housed with Different Environmental Enrichment Materials

Environmental enrichment is widely recognized as an important strategy for improving the welfare of laboratory rodents by promoting species-specific behaviors, reducing stress, and enhancing physiological adaptation. In the present study, animals were maintained either under standard housing conditions without enrichment or exposed to different combinations of commercially available maple cardboard, cardboard rolls, and Kraft paper. Welfare was assessed using a multidimensional approach that included anxiety-related behavioral tests, hematological and biochemical analyses, and growth performance measurements. The results demonstrate that the welfare benefits of environmental enrichment are influenced by the type and combination of materials provided, highlighting the importance of selecting enrichment strategies that are appropriate for the specific housing conditions.