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. 
Alig, B. N., Ferket, P. R., Malheiros, R. D. et al. 2023. The effect of housing environment on commercial brown egg layer production, USDA grade and USDA size distribution. Animals 13(4), 694

Consumer demand for retail cage-free eggs is driving the layer industry towards greater use of extensive housing environments. However, there is limited research on how these environments affect egg production characteristics of brown egg layers...

da Silva, M. I. L., Paz, I. C. de L. A., Jacinto, A. S. et al. 2023. Providing environmental enrichments can reduce subclinical spondylolisthesis prevalence without affecting performance in broiler chickens. PLOS ONE 18(4), e0284087.

Environmental enrichment can increase the occurrence of natural behavior and improve leg health and other animal welfare outcomes in broiler chickens. This study aimed to assess the effects of three environmental enrichments, specifically hay bales...

Dong, Y., Fraley, G. S., Siegford, J. M. et al. 2023. Comparing different environmental enrichments for improving the welfare and walking ability of male turkeys. PLOS ONE 18(5), e0285347.

This study investigated age-related changes in turkey welfare measures (wounds, feather quality (FQ), feather cleanliness, and footpad condition (FCON)) and walking ability (gait) as influenced by different types of environmental enrichment (EE). Tom turkeys (n...

Evans, L., Brooks, G. C., Anderson, M. G. et al. 2023. Environmental complexity and reduced stocking density promote positive behavioral outcomes in broiler chickens. Animals 13(13), 2074.

The objective was to evaluate the impacts of a complex environment and stocking density on Ross 708 broiler chicken behaviors. Eight pens contained either high complexity (HC) or low complexity (LC) environments, and high (HD)...

Hobbiesiefken, U., Urmersbach, B., Jaap, A. et al. 2023. Rating enrichment items by female group-housed laboratory mice in multiple binary choice tests using an RFID-based tracking system. PLOS ONE 18(1), e0278709.

Laboratory mice spend most of their lives in cages, not experiments, so improving housing conditions is a first-choice approach to improving their welfare. Despite the increasing popularity of enrichment, little is known about the benefits...

Lee, G.-H., Kim, K., Jo, W. 2023. Stress evaluation of mouse husbandry environments for improving laboratory animal welfare. Animals 13(2), 249.

Animal welfare is recognized as essential for the coexistence of humans and animals. Considering the increased demand and interest in animal welfare, many methods for improving animal welfare are being devised, but which method reduces...

Malik, A., Zavadil, J. A., Geusz, M. E. 2023. Using bioluminescence to image gene expression and spontaneous behavior in freely moving mice. PLOS ONE 18(1), e0279875.

Bioluminescence imaging (BLI) of gene expression in live animals is a powerful method for monitoring development, tumor growth, infections, healing, and other progressive, long-term biological processes. BLI remains an effective approach for reducing the number...

Palermo Mendes, J., Ribeiro Caldara, F., de Castro Burbarelli, M. F. et al. 2023. Performance and welfare of sows exposed to auditory environmental enrichment in mixed or collective housing systems. Animals 13(7), 1226.

The research aimed to assess the effects of auditory environmental enrichment on sows in mixed housing (caged until 35 days after insemination and then collective pens) or collective housing (caged until 72 h after insemination...

Palumbo, G., Kunze, L. H., Oos, R. et al. 2023. Longitudinal studies on Alzheimer disease mouse models with multiple tracer PET/CT: Application of reduction and refinement principles in daily practice to safeguard animal welfare during progressive aging. Animals 13(11), 1812.

Longitudinal studies on mouse models related to Alzheimer disease (AD) pathology play an important role in the investigation of therapeutic targets to help pharmaceutical research in the development of new drugs and in the attempt...

Quante, S. M., Siewert, V., Palme, R. et al. 2023. The power of a touch: Regular touchscreen training but not its termination affects hormones and behavior in mice. Frontiers in Behavioral Neuroscience 17, 1112780.

Touchscreen-based procedures are increasingly used in experimental animal research. They not only represent a promising approach for translational research, but have also been highlighted as a powerful tool to reduce potential experimenter effects in animal...

Rørvang, M. V., Schild, S.-L. A., Stenfelt, J. et al. 2023. Odor exploration behavior of the domestic pig (Sus scrofa) as indicator of enriching properties of odors. Frontiers in Behavioral Neuroscience 17, 1173298.

Although the sense of smell in pigs is widely recognized as being highly developed, surprisingly little is known about their sensory ability. This study aimed to (a) identify which non-social odors pigs were able to...

Burbidge, C., Beresford, Z., Serrano-Galleg, V. 2023. Validating in-cage mouse enrichment. Animal Technology and Welfare 22(1), 63–67.

There is a wide variety of different types of mouse enrichment currently available, some items of which are more practical than others. Validating items used for providing enrichment can be time consuming and costly, nevertheless...

Skånberg, L., Newberry, R. C., Estevez, I. et al. 2023. Environmental change or choice during early rearing improves behavioural adaptability in laying hen chicks. Scientific Reports 13(1), 6178.

Laying hens are typically moved to a novel environment after rearing, requiring adaptability to cope with change. We hypothesized that the standard rearing of laying hen chicks, in non-changing environments with limited choices (a single...

Veness, A., Coyle, C., Murphy, S. et al. 2023. Minimising aggression in CD-1 and CD-1 background male mice with different enrichment types. Animal Technology and Welfare 22(1), 74–76.

Cage-mate aggression is a well-known problem that is more prevalent in certain strains of mice and is one of the most common reasons for single housing, increased stress levels, premature death and euthanasia. Numerous methods...

Watanabe, S. 2023. Are mirrors aversive or rewarding for mice? Insights from the mirror preference test. Frontiers in Behavioral Neuroscience 17, 1137206.

Research investigating the effects of mirror exposure in mice found that the presence of mirrors has similar effects to the presence of cage mates. Restraint in a small holder induces hyperthermia (stress-induce hyperthermia: SIH) in...

Monteiro, M. S., Muro, B. B. D., Carnevale, R. F. et al. 2023. The beneficial effects of providing prepartum sows with nesting materials on farrowing traits, piglet performance and maternal behavior: A systematic review and meta-analysis. Applied Animal Behaviour Science 259, 105795.

Sows are highly motivated to engage in nest-building behavior prior to farrowing. Studies have shown that providing nesting material to farrowing sows reduces the occurrence of redirected nest-building behaviors, improves farrowing traits and maternal behavior...

Vas, J., BenSassi, N., Vasdal, G. et al. 2023. Better welfare for broiler chickens given more types of environmental enrichments and more space to enjoy them. Applied Animal Behaviour Science 261, 105901.

Providing an increased variety of environmental enrichment options, with sufficient space to use them, could increase the behavioural expression of positive affective states in production animals. The goal of this study was to investigate associations...

Veldkamp, F., Garcia-Faria, T. I., Witjes, V. L. et al. 2023. Validation of non-invasive sensor technologies to measure interaction with enrichment material in weaned fattening pigs. Applied Animal Behaviour Science 263, 105923.

Measuring animal behaviour is important in the assessment of animal welfare. When interaction with the enrichment material (EM) can be measured, it can be used for detecting an increasing/decreasing interest in a certain EM. In...

Beekmans, M. H. C., Vinke, C. M., Maijer, A. et al. 2023. Increasing foraging times with appetitive and consummatory foraging enrichment in grey parrots (Psittacus erithacus). Applied Animal Behaviour Science 265, 105986.

Foraging enrichment is considered one of the most effective ways to enhance expression of species-typical behaviours and prevent the development of abnormal (repetitive) behaviours in captive animals. However, foraging enrichments for parrots have thus far...

Bárdos, B., Nagy, I., Gerencsér, Z. et al. 2022. Nest material preference of wild mouse species in laboratory housing. Applied Sciences 12(11), 5750.

Our research examined the nest-building characteristics of two mouse species native to Hungary, the mound-building mouse (Mus spicilegus) and the house mouse (Mus musculus), under laboratory housing conditions. In indoor housing, the nest-building material plays...

Meira, J. E. S., Nogueira-Filho, S. L. G., Mendl, M. et al. 2023. Responses to environmental enrichment are associated with personality characteristics in chestnut-bellied seed finches (Sporophila angolensis). Behavioural Processes 204, 104801.

Environmental enrichment (EE) is used to promote natural behaviours in captive animals and may hold promise as a form of pre-release training, a strategy for improving coping skills of translocated birds. We investigated the use...

Alvarez-Hernandez, N., Vallejo-Timarán, D., de Jesús Rodriguez, B. 2023. Adapted original music as an environmental enrichment in an intensive pig production system reduced aggression in weaned pigs during regrouping. Animals 13(23), 3599.

In intensive swine production systems,, the practice of regrouping unfamiliar pigs is common, often leading to aggressive behavior. Although the effect of different musical genres composed for humans has been evaluated in pigs to mitigate...

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...

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...