Elevating Animal Welfare and Promoting Natural Behaviors with Environmental Enrichment
Research animal enrichment products enhance laboratory animal well-being and support adherence to the 3Rs (Replacement, Reduction, Refinement) in discovery and nonclinical development.
While Institutional Animal Care and Use Committees (IACUCs) and international organizations consider enrichment a standard component of humane laboratory practices, many researchers are increasingly recognizing the value of laboratory animal enrichment materials and devices in reducing stress and the incidence of abnormal behaviors, such as stereotypies, persistent fighting, or excessive grooming.
Recent research has also found that environmental enrichment for rodents decreased corticosterone concentrations, reduced fear-related responses, and increased anti-anxiety characteristics and exploratory behaviors compared with standard-housed animals, without affecting the integrity or reproducibility of the results.1
To help researchers better understand species-appropriate enrichment and how to elevate animal welfare and research outcomes, we’re providing an overview of enrichment materials and their role in promoting four natural behaviors.
1. Nesting: Creating a Stimulating Environment
Rodents provided with effective enrichment tend to display a range of natural behaviors, including nest building, digging, and burrowing. Ideal nesting materials should be easy for them to manipulate and carry, while still maintaining their structure to provide stability and support thermoregulation.
Nesting enrichment also encourages natural foraging and exploratory behaviors, as rodents engage in ripping, shredding, and rearranging materials to create comfortable and stimulating environments.
In toxicology studies, or when working with nude mice, selecting dust-free or low-dust nesting materials is especially important, as it helps minimize respiratory irritation and supports overall animal welfare.
2. Playing: Promoting Well-Being with Enrichment Toys
Mice, rats, hamsters, cotton rats, ferrets, and rabbits use enrichment tunnels for hiding, playing, nesting, foraging, shredding, and gnawing, thereby helping to reduce boredom and stress.
Play tunnels and other similar structures can also serve as a valuable tool for calmer, non-aversive animal handling, as handlers can guide rodents into the tunnel, seal the ends, and easily transfer them to another cage or shipping container.
3. Chewing: Satisfying Instinctive Needs
Rodents have innate needs for gnawing, climbing, and exercise. Providing materials for chewing and gnawing is essential for maintaining the physical and behavioral health of rodents and other small laboratory animals. Because these species possess teeth that grow continuously throughout their lives, gnawing on appropriate enrichment items—such as wood blocks, balls or specialized fiber materials—is necessary to prevent overgrowth and ensure proper dental wear.
Beyond this physiological function, these activities serve as a powerful form of behavioral enrichment by allowing animals to engage in natural foraging and manipulative behaviors, which alleviates boredom and reduces the incidence of maladaptive actions like barbering or cage-bar chewing. By promoting natural activity and providing a productive outlet for their innate drive to chew, these items significantly enhance the animal's overall welfare and comfort within the research environment.
4. Sheltering: Providing Laboratory Animal Hiding Spaces and Housing
Sheltering enrichment—such as igloos, tunnels, and designated hideaways—is vital for supporting the natural behaviors and well-being of laboratory animals. These structures create essential, burrow-like environments where animals can nest, rest, and retreat, effectively reducing stress and fostering positive social interactions by offering grouped animals a needed sanctuary.
Beyond providing a crucial sense of security, these spaces encourage exploration and serve as a valuable, non-aversive tool for gentle handling. Furthermore, shelters satisfy the fundamental instinct to protect offspring; by providing a secluded area to house litters away from other animals and environmental stressors, they allow for natural, instinctual maternal care in a secure setting.
The Role of Enrichment in Promoting More Robust Research Outcomes
Enrichment is increasingly recognized as an essential element of animal welfare, supporting more reliable and biologically relevant research outcomes. Enriched environments encourage species-typical behaviors such as exploration, nesting, and social interaction, leading to responses that better reflect physiology and potentially improve the relevance of your findings.
Try Our Laboratory Enrichment Materials for Free
Our team at Inotiv is here to help you maintain consistency and reliability in your research. You can Request a Free Enrichment Sampler Box to see how our enrichment materials help enhance well-being.
For more information on our welfareplus+® Rodent Enrichment Solutions or other related research products, please contact us at teklad@inotiv.com.
Reference:
Domínguez-Oliva A, Hernández-Avalos I, Bueno-Nava A, et al. Environmental enrichment for laboratory rats and mice: endocrine, physiological, and behavioral benefits of meeting rodents' biological needs. Front Vet Sci. 2025 Jul 10;12:1622417.
