Refinement Database

Database on Refinement of Housing, Husbandry, Care, and Use of Animals in Research

This database, created in 2000, is updated every four months with newly published scientific articles, books, and other publications related to improving or safeguarding the welfare of animals used in research.

Tips for using the database:

  • This landing page displays all of the publications in the database.
  • Use the drop-down menus to filter these publications by Animal Type, Setting, and/or Topic.
  • Clicking on a parent category (e.g., Rodent) will include publications relating to all the items in that category (e.g., Chinchilla, Gerbil, Guinea Pig, etc.).
  • You may also add a keyword to further narrow your search.
  • Please note that at this time, only publications dated 2010 or later (with some exceptions) can be filtered by Animal Type and Topic, and only publications dated 2020 or later (with some exceptions) can be filtered by Setting. Most publications older than 2010 can only be searched by keyword. 
Chakravarty, S., Donoghue, J., Waite, A. S. et al. 2023. Closed-loop control of anesthetic state in nonhuman primates. PNAS Nexus 2(10), 293.

Research in human volunteers and surgical patients has shown that unconsciousness under general anesthesia can be reliably tracked using real-time electroencephalogram processing. Hence, a closed-loop anesthesia delivery (CLAD) system that maintains precisely specified levels of...

Baskir, E., Parsons, A., Elden, M. et al. 2023. Quantifying acute behavioral reactions of Bali mynas (Leucopsar rothschildi) to environmental and progressively challenging enrichment. Journal of Zoological and Botanical Gardens 4(1), 176–190.

Animals use specific behaviors and skills to overcome challenges and access resources. Environmental enrichment is provided to animals in human care to both promote species-appropriate behaviors and reduce undesired behaviors. Feather pecking in birds is...

Bertrand, D. A., Berman, C. M., Heistermann, M. et al. 2023. Effects of tourist and researcher presence on fecal glucocorticoid metabolite levels in wild, habituated Sulawesi crested macaques (Macaca nigra). Animals 13(18), 2842.

Ecotourism managers and researchers often assume that apparently habituated primate groups no longer experience adverse consequences of prolonged exposure to tourists or researchers. We examined the effects of tourists and researchers on fecal glucocorticoid metabolite...

Bohn, L., Bierbaum, L., Kästner, N. et al. 2023. Structural enrichment for laboratory mice: Exploring the effects of novelty and complexity. Frontiers in Veterinary Science 10.

Providing structural enrichment is a widespread refinement method for laboratory rodents and other animals in captivity. So far, animal welfare research has mostly focused on the effect of increased complexity either by accumulating or combining...

Bramati, G., Stauffer, P., Nigri, M. et al. 2023. Environmental enrichment improves hippocampus-dependent spatial learning in female C57BL/6 mice in novel IntelliCage sweet reward-based behavioral tests. Frontiers in Behavioral Neuroscience 17.

The IntelliCage is an automated home-cage system that allows researchers to investigate the spontaneous behavior and learning abilities of group-housed mice. The IntelliCage enables us to increase the standardization and reproducibility of behavioral outcomes by...

Brando, S., Norman, M. 2023. Handling and training of wild animals: Evidence and ethics-based approaches and best practices in the modern zoo. Animals 13(14), 2247.

There is an ethical responsibility to provide all animals living in human care with optimal and positive well-being. As animals living in zoos and aquariums frequently interact with their human caregivers as part of their...

Calapai, A., Pfefferle, D., Cassidy, L. C. et al. 2023. A touchscreen-based, multiple-choice approach to cognitive enrichment of captive rhesus macaques (Macaca mulatta). Animals 13(17), 2702.

Research on the psychological and physiological well-being of captive animals has focused on investigating different types of social and structural enrichment. Consequently, cognitive enrichment has been understudied, despite the promising external validity, comparability, and applicability...

Campbell-Ward, M. 2023. Quality-of-life assessments in zoo animals: Not just for the aged and charismatic. Animals 13(21), 3394

Zoos should aim to provide all of their animals with a good quality of life (QoL) throughout all life stages. In parallel with the evolution of QoL assessment questionnaires and tools in human and domestic...

Clark, F. E. 2023. In the zone: Towards a comparative study of flow state in primates. Animal Behavior and Cognition 10(1), 62–88.

Flow is an altered state of feeling ‘in the zone’ when fully absorbed in a challenge and is associated with positive affective state (feelings). Despite almost five decades of research, Flow has not yet been...

Cordeira, J. 2023. Daily replacement of very high-fat diet stabilizes food intake and improves mouse welfare by ensuring food quality. PLOS ONE 18(9), e0291347.

Researchers are obligated to ensure food quality and provide laboratory animals with a palatable diet. Factors influencing the quality and palatability of very high-fat diet (VHFD), a widely used rodent diet, however, are understudied. We...

Dietrich, T., Aigner, A., Hildebrandt, A. et al. 2023. Nesting behavior is associated with body weight and grip strength loss in mice suffering from experimental arthritis. Scientific Reports 13(1), 23087.

Objective animal health evaluation is essential to determine welfare and discomfort in preclinical in vivo research. Body condition scores, body weight, and grimace scales are commonly used to evaluate well-being in murine rheumatoid arthritis (RA)...

Englund, M. D., Cronin, K. A. 2023. Choice, control, and animal welfare: Definitions and essential inquiries to advance animal welfare science. Frontiers in Veterinary Science 10.

The ways in which humans can support good welfare for animals in their care is an ongoing subject of debate: some place emphasis on the animals’ physical health; others, on animals’ ability to live “natural...

Esparza, K. 2023, August. Moving away from soiled bedding sentinels—The (R)evolution in rodent health screening. Animal Technology and Welfare 22(2), 158–160.

Traditional health monitoring methods consisted of Soiled Bedding Sentinels (SBS (i.e. animals exposed to dirty bedding from colony animals)), which require the euthanasia of SBS. Numerous studies have demonstrated that SBS may not accurately represent...

Fultz, A., Lewis, R., Kelly, L. et al. 2023. Behavioral welfare research for the management of sanctuary chimpanzees (pan troglodytes). Animals 13(16), 2595.

Chimp Haven is a sanctuary for chimpanzees retired from biomedical research, rescued from the pet trade, or re-homed after other organizations could no longer care for them. To provide optimal care for over 300 chimpanzees...

Klabukov, I., Shestakova, V., Krasilnikova, O. et al. 2023. Refinement of animal experiments: Replacing traumatic methods of laboratory animal marking with non-invasive alternatives. Animals 13(22), 3452.

Reliable methods for identifying rodents play an important role in ensuring the success of preclinical studies. However, animal identification remains a trivial laboratory routine that is not often discussed, despite the fact that more than...

rueger, J. C., Boecker, M., Gauggel, S. et al. 2023. Using photographs for rating severity degrees of clinical appearance in research mice enables valid discrimination of extreme but not mild and moderate conditions: A pilot study. PLOS ONE 18(11), e0287965.

To ensure good animal welfare in laboratory research and in stockbreeding severity ratings of the animals´ wellbeing are essential. The current study investigated how valid raters can evaluate different severity degrees of clinical appearance and...

Lang, B., Kahnau, P., Hohlbaum, K. et al. 2023. Challenges and advanced concepts for the assessment of learning and memory function in mice. Frontiers in Behavioral Neuroscience 17.

The mechanisms underlying the formation and retrieval of memories are still an active area of research and discussion. Manifold models have been proposed and refined over the years, with most assuming a dichotomy between memory...

Loader, A., Rose, P. 2023. Age-related change in the association choices of two species of juvenile flamingos. Animals 13(16), 2623.

Flamingos are colonial species commonly kept in zoos, well known for their bright plumage and elaborate courtship displays. This project aimed to determine the differences in flock position and association preferences of juvenile Greater Flamingos...

Marin, N., Moragon, A., Gil, D. et al. 2023. Acclimation and blood sampling: Effects on stress markers in C57Bl/6J mice. Animals 13(18), 2816.

Blood sampling in rodents is common practice in scientific studies. Some of the refined methods widely used are the puncture of the saphenous vein or tail vein, or even tail docking. The handling needs of...

Martinez-Lopez, S., Angel-Gomis, E., Sanchez-Ardid, E. et al. 2023. The 3Rs in experimental liver disease. Animals 13(14), 2357.

Patients with cirrhosis present multiple physiological and immunological alterations that play a very important role in the development of clinically relevant secondary complications to the disease. Experimentation in animal models is essential to understand the...

Mooney, A., McCall, K., Bastow, S. et al. 2023. Changes in environment and management practices improve foot health in zoo-housed flamingos. Animals 13(15), 2483.

Foot lesions are a highly prevalent phenomenon among zoo-housed flamingos, with up to 99.8% of birds affected. These lesions are a recognized welfare concern, increasing the likelihood of bacterial infections, and even septicemia. Although several...

Oikawa, T., Nomura, K., Hara, T. et al. 2023. A fine-scale and minimally invasive marking method for use with conventional tungsten microelectrodes. eNeuro 10(9), ENEURO.0141-23.2023.

In neurophysiology, achieving precise correlation between physiological responses and anatomic structures is a significant challenge. Therefore, the accuracy of the electrode marking method is crucial. In this study, we describe a tungsten-deposition method, in which...

Parsons, M. H., Stryjek, R., Fendt, M. et al. 2023. Making a case for the free exploratory paradigm: Animal welfare-friendly assays that enhance heterozygosity and ecological validity. Frontiers in Behavioral Neuroscience 17.

Rodents, laboratory rats and mice, have been used as models in experimental research for almost two centuries (Keeler, 1947; Bolles and Woods, 1964; Nishioka, 1995; Guénet and Bonhomme, 2003). During this time, it has been...

Pérez-Martín, E., Coto-Vilcapoma, A., Castilla-Silgado, J. et al. 2023. Refining stereotaxic neurosurgery techniques and welfare assessment for long-term intracerebroventricular device implantation in rodents. Animals 13(16), 2627.

Stereotaxic surgeries enable precise access to specific brain regions, being of particular interest for chronic intracerebroventricular drug delivery. However, the challenge of long-term studies at this level is to allow the implantation of drug storage...

Piekarski, N., Hobbs, T. R., Jacob, D. et al. 2023. A comparison of oocyte yield between ultrasound-guided and laparoscopic oocyte retrieval in rhesus macaques. Animals 13(19), 3017.

Obtaining quality oocytes is a prerequisite for ART-based studies. Here we describe a method for transabdominal ultrasound-guided (US) oocyte retrieval in rhesus macaques (Macaca mullata) and compare it to the standard surgical approach using laparoscopy...