When you think about animals in a research lab, you might picture sterile rooms and bare floors. But a team at the Washington National Biomedical Research Center (WaNBRC) is showing that the ground beneath a primate’s feet can actually change the future of medicine.
Rita Bellanca, who leads the Behavior Management Services team, recently worked with BMS teammates Grace Lee and Jessica Khuu, along with lead author Ken Sayers from the Southwest National Primate Reseach Center at the Texas Biomedical Research Instituate to show how something called “complex substrates” can transform animal care, and by extension, research. The paper was a collaboration with WaNBRC, multiple research centers and Johns Hopkins University.
Complex substrates are basically materials that add texture and variety to an animal’s environment. You might think of it as just “bedding,” but it includes things like wood shavings, straw, sand, and even naturalistic flooring called biofloors. These materials give animals a way to interact with their surroundings instead of sitting on a hard surface.
“Bedding is actually just one type of complex substrate,” Bellanca said. “In the paper, a substrate is defined broadly as the surface an animal interacts with, while complex substrates are materials that add novelty, variability, texture, and opportunities for interaction.” She adds, “What makes them important is that they are manipulable and dynamic, allowing animals to engage with and even modify their environment, something that a bare floor simply cannot provide.”
Bellanca and her research partners did a deep dive into how these materials work in the real world. “This paper combines a comprehensive literature review with real-world input from primate research centers,” she said. “We synthesized decades of published research on complex substrates and bedding and paired that with an informal survey and focus group discussions involving professionals across multiple National Primate Research Centers and affiliated institutions, including Johns Hopkins.”
For the public, this work reveals the granular details of animal welfare that the team at the WaNBRC thinks about. It is not just about keeping a cage clean; it is about understanding the deep biological needs of the animals.
This level of detail matters because primates have an evolved need to explore Bellanca said. “Many primates naturally spend a large portion of their time foraging, exploring, and manipulating their environment. Complex substrates allow them to engage in these species-typical behaviors, such as searching for hidden food, digging, and tactile exploration.”
This is a win for both the animals and for human health. When animals are less stressed and more active, the scientific data they provide is more accurate,” Bellanca said. “Animals that are more engaged and able to express natural behaviors tend to be psychologically healthier, less stressed, and more behaviorally stable,” she said. “This can lead to more reliable and meaningful research data because the animals more closely reflect their species’ natural biology.”
By matching a primate’s environment to its natural history, the team is ensuring that the science is as strong as it can be. As Bellanca puts it, “If we look to primates’ natural history and design environments that reflect it, we support both animal welfare and better science.”