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. 
Dawkins, M. S. 2024. Active walking in broiler chickens: A flagship for good welfare, a goal for smart farming and a practical starting point for automated welfare recognition. Frontiers in Veterinary Science 10.

Automated assessment of broiler chicken welfare poses particular problems due to the large numbers of birds involved and the variety of different welfare measures that have been proposed. Active (sustained, defect-free) walking is both a...

Lambert, H., Cornish, A., Waley, D. 2024. The value of regulating stocking densities in aquaculture must not be dismissed: A reply to Saraiva et al. 2022. Frontiers in Veterinary Science 10.

We would like to rebut the argument made by Saraiva et al. (1) in their paper “Finding the “golden stocking density”: a balance between fish welfare and farmers' perspectives,” that stocking densities should not be...

Robinson, L. M., Weiss, A. (Eds.) 2023. Nonhuman Primate Welfare: From History, Science, and Ethics to Practice. Springer, Cham, Switzerland. 671 p.

This volume reviews the broad topic of welfare in nonhuman primates under human care. Chapters detail the history of primates in captivity, ethical and legal issues surrounding the use of nonhuman primates as entertainment or...

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...

Ausderau, K. K., Colman, R. J., Kabakov, S. et al. 2023. Evaluating depression- and anxiety-like behaviors in non-human primates. Frontiers in Behavioral Neuroscience 16, 1006065.

Depression and anxiety are some of the most prevalent and debilitating mental health conditions in humans. They can present on their own or as co-morbidities with other disorders. Like humans, non-human primates (NHPs) can develop...

Cohen, S., Ho, C. 2023. Review of rat (Rattus norvegicus), Mouse (mus musculus), Guinea pig (Cavia procellus), and rabbit (Oryctolagus cuniculus) indicators for welfare assessment. Animals 13(13), 2167.

The monitoring and assessment of animals is important for their health and welfare. The appropriate selection of multiple, validated, and feasible welfare assessment indicators is required to effectively identify compromises or improvements to animal welfare...

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)...

Hernández-Arteaga, E., Ågmo, A. 2023. Seminatural environments for rodent behavioral testing: A representative design improving animal welfare and enhancing replicability. Frontiers in Behavioral Neuroscience 17, 1192213.

The low replicability of scientific studies has become an important issue. One possible cause is low representativeness of the experimental design employed. Already in the 1950’s, Egon Brunswick pointed out that experimental setups ideally should...

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...

Łapiński, S., Niedbała, P., Markowska, K. et al. 2023. The effects of age, size, and cage complexity on the behaviour of farmed female chinchillas (Chinchilla lanigera). Scientific Reports 13(1), 6108.

Even though chinchillas have been farmed for a century, there are not many studies concerning their behaviour in captivity or their optimal housing conditions, both of which are important factors in the assessment of their...

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...

Martín, J., Barja, I., Rodríguez-Ruiz, G. et al. 2023. Hidden but potentially stressed: A non-invasive technique to quantify fecal glucocorticoid levels in a fossorial amphisbaenian reptile. Animals 13(1), 109.

To understand wildlife responses to the changing environment, it is useful to examine their physiological responses and particularly their endocrine status. Here, we validated an enzyme immunoassay (EIA) to non-invasively quantify fecal corticosterone metabolites (FCM)...

Moise, R. I., Eccles, G. R., Mettke-Hofmann, C. 2023. Enclosure background preferences differ between sexes and color morphs in the Gouldian finch. Animals 13(8), 1353.

Most wild animals camouflage well into their environment, providing protection from predators, whereas captive animals often contrast with their background. This can cause stress for the animal, which may perceive it as being exposed. Theory...

Paneru, B., Pent, G. J., Nastasi, S. et al. 2023. Effect of silvopasture system on fearfulness and leg health in fast-growing broiler chickens. PLOS ONE 18(3), e0282923.

A silvopasture system intentionally integrates trees, forages, and livestock, allowing dual land use. These systems can provide high-quality habitat for broiler chickens; however, such systems have not been widely adopted by the broiler industry in...

Silva-Reis, R., Faustino-Rocha, A. I., Silva, J. et al. 2023. Studying and analyzing humane endpoints in the fructose-fed and streptozotocin-injected rat model of diabetes. Animals 13(8), 1397.

This work aimed to define a humane endpoint scoring system able to objectively identify signs of animal suffering in a rat model of type 2 diabetes. Sprague-Dawley male rats were divided into control and induced...

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...

Sokołowicz, Z., Dykiel, M., Topczewska, J. et al. 2023. A comparison of the plumage condition of three egg-laying poultry genotypes housed in non-cage systems. Animals 13(2), 185.

The study covered a total of 810 hens in 3 groups (housing systems) of 270 hens each. The plumage condition of laying hens raised in various types of alternative housing systems, i.e., in deep litter...

Swan, J., Boyer, S., Westlund, K. et al. 2023. Decreased levels of discomfort in repeatedly handled mice during experimental procedures, assessed by facial expressions. Frontiers in Behavioral Neuroscience 17, 1109886.

Mice are the most commonly used laboratory animal, yet there are limited studies which investigate the effects of repeated handling on their welfare and scientific outcomes. Furthermore, simple methods to evaluate distress in mice are...

Zieliński, D. 2023. The effect of enrichment on leopard geckos (Eublepharis macularius) housed in two different maintenace systems (rack system vs. Terrarium). Animals 13(6), 1111.

The aim of this study was to test the usefulness of environmental enrichment for Eublepharis macularius depending on the maintenance method (terrarium vs. rack system). The hypothesis was that reptiles kept in an extremely low-stimulus...

Goodenough, A. E., Sewell, A., McDonald, K. 2023. Behavioural patterns in zoo-housed Humboldt penguins (Spheniscus humboldti) revealed using long-term keeper-collected data: Validation of approaches and improved husbandry. Applied Animal Behaviour Science 258, 105811.

Given the increasing obligation to elevate animal welfare beyond minimum expectations, zoos need robust mechanisms to monitor physical activity and species-appropriate behaviours. This is not without challenge as animal behaviour can vary seasonally or be...

O’Brien, S. L., Cronin, K. A. 2023. Doing better for understudied species: Evaluation and improvement of a species-general animal welfare assessment tool for zoos. Applied Animal Behaviour Science 264, 105965.

Accredited zoos and aquariums are required to have a welfare assessment process in place for the animals in their care. However, welfare assessment theoretical frameworks and methodologies vary widely. Previous studies have shown that taxonomic...

Moëne, O. L., Larsson, M. 2023. A new tool for quantifying mouse facial expressions. ENeuro 10(2) ENEURO.0349-22.2022.

Facial expressions are an increasingly used tool to assess emotional experience and affective state during experimental procedures in animal models. Previous studies have successfully related specific facial features with different positive and negative valence situations...

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...

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)...