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. 
Stevens, C., Hammonds, T., Hinchcliffe, J. et al. 2023. Report of the 2022 RSPCA/UFAW Rodent Welfare Group Meeting. Animal Technology and Welfare 22(2), 91–100.

The RSPCA/UFAW Rodent Welfare Group has held a one-day meeting every autumn for the last 29 years, so that its members can discuss current welfare research, exchange views on welfare issues and share experiences of...

Tanaka, Y., Nakata, T., Hibino, H. et al. 2023. Classification of multiple emotional states from facial expressions in head-fixed mice using a deep learning-based image analysis. PLOS ONE 18(7), e0288930.

Facial expressions are widely recognized as universal indicators of underlying internal states in most species of animals, thereby presenting as a non-invasive measure for assessing physical and mental conditions. Despite the advancement of artificial intelligence-assisted...

Caires, C. R. S., Bossolani-Martins, A. L. 2023. Which form of environmental enrichment is most effective in rodent models of autism? Behavioural Processes 211, 104915.

Environmental enrichment (EE) is known to produce experience-dependent changes in the brains and behaviors of rodents, and it has therefore been widely used to study neurodevelopmental disorders, including autism. Current studies show significant protocol variation...

Wowk, Z. M., Behie, A. M. 2023. The influence of olfactory enrichment on the behavior of two captive New World primates: Black-capped capuchin (Sapajus apella) and common marmoset (Callithrix jacchus). Zoo Biology 42(2), 231–242.

Environmental enrichment is an animal husbandry principle that seeks to provide the stimuli necessary for the optimal physiological and psychological well-being of animals. Due to primates having highly developed visual systems, there have been limited...

Xu, L., Jiao, M., Cui, Z.-L. et al. 2023. Enriched environment during adolescence modulates lipid metabolism and emotion-related behaviors in mice. Journal of Applied Animal Welfare Science 26(2), 218–228.

Enriched environment (EE) is an important animal experimental paradigm to decipher gene-environment interaction. It is thought to be efficient in aiding recovery from certain metabolism disorders or cognitive impairments. Recently, the effects of EE during...

LaFollette, M. R., Cloutier, S., Brady, C. M. et al. 2023. Benchmarking enrichment efforts in the US & Canada across species and enrichment categories. JAALAS 62(4), 303–316.

Enrichment is important for animal welfare and data quality. Provision of enrichment opportunities varies between species and enrichment category. However, data benchmarking these differences does not exist. Our objective was to characterize enrichment provision and...

Ratuski, A. S., Weary, D. M. 2022. Environmental enrichment for rats and mice housed in laboratories: A metareview. Animals 12(4), 414.

Environmental enrichment has been widely studied in rodents, but there is no consensus on what enrichment should look like or what it should achieve. Inconsistent use of the term “enrichment” creates challenges in drawing conclusions...

Medina, A. 2022. Creative enrichment for nonhuman primates. Laboratory Animal Science Professional 10(1) (January/February), 42-43.

Providing novel and creative enrichments for nonhuman primates improves their mental wellbeing and is thus an important aspect of all husbandry programs. These enrichments are often presented through variations in diet, toys, and environmental features...

Buchanan, K. 2022. DIY: Ants on a log. Laboratory Animal Science Professional 10(1) (January/February), 44.

This traditional snack has a variety of options for NHP enrichment. From fruit to cereals, get creative with the “ants” and remember to consider different fillings for the celery log.

Aird, T., Pierre, P. J. 2022. Refining enrichment toy interactions in common marmosets through usage assessment. Laboratory Animal Science Professional 10(1) (January/February), 64-66.

Apart from species-typical foraging behavior, a large body of the literature addresses enriching captive marmoset environments through structural and housing adaptations to promote activity and exploration. These studies simulate vertical elements and climbing substrates in...

Hobbiesiefken, U., Mieske, P., Lewejohann, L. et al. 2021. Evaluation of different types of enrichment - their usage and effect on home cage behavior in female mice. PLOS ONE 16(12), e0261876.

Numerous studies ascertained positive effects of enriched environments on the well-being of laboratory animals including behavioral, physiological and neurochemical parameters. Conversely, such conclusions imply impaired animal welfare and health in barren husbandry conditions. Moreover, inappropriate...

Stevens, C., Dobbinson, K., Brook, E. et al. 2022. Report of the 2021 RSPCA/UFAW Rodent Welfare Group meeting. Animal Technology and Welfare 21(2), 83-91.

The RSPCA/UFAW Rodent Welfare Group has held a one-day meeting every autumn for the last 28 years, so that its members can discuss current welfare research, exchange views on welfare issues and share experiences of...

Knaebe, B., Weiss, C. C., Zimmermann, J. et al. 2022. The promise of behavioral tracking systems for advancing primate animal welfare. Animals 12(13), 1648.

Recent years have witnessed major advances in the ability of computerized systems to track the positions of animals as they move through large and unconstrained environments. These systems have so far been a great boon...

Aldhshan, M. S., Mizuno, T. M. 2022. Effect of environmental enrichment on aggression and the expression of brain-derived neurotrophic factor transcript variants in group-housed male mice. Behavioural Brain Research 433, 113986.

Social and environmental factors influence behavior via modulation of brain physiological functions. Environmental enrichment (EE) is an animal housing technique that provides complex sensory, motor, and social stimulation, leading to modifications in the innate aggressiveness...

Mieske, P., Hobbiesiefken, U., Fischer-Tenhagen, C. et al. 2022. Bored at home?—A systematic review on the effect of environmental enrichment on the welfare of laboratory rats and mice. Frontiers in Veterinary Science 9, 899219.

Boredom is an emotional state that occurs when an individual has nothing to do, is not interested in the surrounding, and feels dreary and in a monotony. While this condition is usually defined for humans...

de França Santos, M., de Menezes Galvão, A. C., Santos Silva, F. et al. 2022. Welfare improvement by enrichment programs in common marmoset females under social isolation. Journal of Applied Animal Welfare Science 25(3), 297-309.

Animal welfare is critical to buffer stress in captive animals and to ensure the reliability of data from studies. The most usual environmental enrichment technique (EE) for social non-human primates is the social enrichment. However...

Ramírez-Rodríguez, G. B., Gutiérrez-Vera, B., Ortiz-López, L. et al. 2022. Environmental enrichment: Dissociated effects between physical activity and changing environmental complexity on anxiety and neurogenesis in adult male Balb/C mice. Physiology & Behavior 254, 113878.

Several factors, including environmental modifications, stimulate neuroplasticity. One type of neuroplasticity consists in the generation of new neurons in the dentate gyrus of the hippocampus. Neurogenesis is modulated by environmental enrichment (ENR, tunnels plus running...

MacLellan, A., Nazal, B., Young et al. 2022. Waking inactivity as a welfare indicator in laboratory mice: Investigating postures, facial expressions and depression-like states. Royal Society Open Science 9(11), 221083.

Animal welfare assessment relies on valid and practical indicators of affect. In mice, the most widely used research vertebrates, lying still with eyes open, inactive-but-awake (IBA) in the home cage, has potential to be one...

Prescott, M. J., Leach, M. C., Truelove, M. A. 2022. Harmonisation of welfare indicators for macaques and marmosets used or bred for research. F1000Research 11, 272.

Background: Accurate assessment of the welfare of non-human primates (NHPs) used and bred for scientific purposes is essential for effective implementation of obligations to optimise their well-being, for validation of refinement techniques and novel welfare...

Mieske, P., Hobbiesiefken, U., Fischer-Tenhagen, C. et al. 2022. Bored at home?—A systematic review on the effect of environmental enrichment on the welfare of laboratory rats and mice. Frontiers in Veterinary Science 9, 899219.

Boredom is an emotional state that occurs when an individual has nothing to do, is not interested in the surrounding, and feels dreary and in a monotony. While this condition is usually defined for humans...

Talbot, S. R., Struve, B., Wassermann, L. et al. 2022. RELSA—A multidimensional procedure for the comparative assessment of well-being and the quantitative determination of severity in experimental procedures. Frontiers in Veterinary Science 9, 937711.

Good science in translational research requires good animal welfare according to the principles of 3Rs. In many countries, determining animal welfare is a mandatory legal requirement, implying a categorization of animal suffering, traditionally dominated by...

Cait, J., Cait, A., Scott, R. W. et al. 2022. Conventional laboratory housing increases morbidity and mortality in research rodents: Results of a meta-analysis. BMC Biology 20(1), 15.

Over 120 million mice and rats are used annually in research, conventionally housed in shoebox-sized cages that restrict natural behaviours (e.g. nesting and burrowing). This can reduce physical fitness, impair thermoregulation and reduce welfare (e.g...

Burlingame, L. A., Gaskill, B. N., Lofgren, J. L. S. 2021. Identification of sick or dead mice (Mus musculus) housed with 6 grams of crinkle paper nesting material. JAALAS 60(1), 18-27.

Although nesting material is beneficial to the welfare of laboratory mice, provision of appropriate amounts may impair visualization of the mice. In anticipation of our academic research institution transitioning to providing 6 grams of nesting...

Allen, P. S., Lawrence, J., Stasula, U. et al. 2021. Effects of compressed paper bedding on mouse breeding performance and recognition of animal health concerns. JAALAS 60(1), 28-36.

The combination of bedding substrate and nesting material within the microenvironment of mice is an important consideration for animal care programs in regard to optimizing animal wellbeing. We used 3 general or breeding mouse colonies...

Oatess, T. L., Harrison, F. E., Himmel, L. E. et al. 2021. Effects of acrylic tunnel enrichment on anxiety-like behavior, neurogenesis, and physiology of C57BL/6J mice. JAALAS 60(1), 44-53.

Environmental enrichment for mice lags behind the standard enrichment offered to other laboratory rodents due to concerns about environmental variability and, in specific contexts, aggression. Our objective in this study was to evaluate concerns that...