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. 
Kaiser, S., Korte, A., Wistuba, J. et al. 2023. Effects of castration and sterilization on baseline and response levels of cortisol—A case study in male guinea pigs. Frontiers in Veterinary Science 9, 1093157.

An uncontrolled reproduction of animals in human hands should be avoided. To meet this goal, animals are widely castrated, i.e., the gonads are completely removed. Since the gonads are the most important source of sex...

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...

Xu, J. J., Lucero, M. Y., Herndon, N. L. et al. 2023. Comparison of a minimally invasive transthoracic approach and a surgical method for intrapleural injection of tumor cells in mice. Comparative Medicine 73(2), 120–126.

Intrapleural injections can be used in mice to deliver therapeutic and diagnostic agents and to model human disease processes (for example, pleural fluid accumulation, malignant pleural disease, and lung cancers). In the context of establishing...

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...

Shanazz, K., Nalloor, R., Vazdarjanova, A. 2023. A mild stressor induces short-term anxiety and long-term phenotypic changes in trauma-related behavior in female rats. Frontiers in Behavioral Neuroscience 17.

IntroductionAnxiety and anxiety-influenced disorders are sexually dimorphic with women being disproportionately affected compared to men. Given the increased prevalence in women and the documented differences in anxiety and trauma behavior between male and female rats...

van Zeeland, Y. R. A., Schoemaker, N. J., Lumeij, J. T. 2023. Contrafreeloading indicating the behavioural need to forage in healthy and feather damaging Grey parrots. Animals 13(16), 2635.

Contrafreeloading (CFL) is a concept that describes the preference of an animal to work for food even when identical food is freely available, and reflects an intrinsic motivation to engage in foraging-related activities. However, altered...

Wang, C., Yang, C., Zeng, Y. et al. 2023. GnRH-immunocastration: An alternative method for male animal surgical castration. Frontiers in Veterinary Science 10.
Baker, P. E., Nicol, C. J., Weeks, C. A. 2022. The effect of hard pecking enrichment during rear on feather cover, feather pecking behaviour and beak length in beak-trimmed and intact-beak laying hen pullets. Animals 12(6), 674.

Injurious pecking, commonly controlled by beak trimming (BT), is a widespread issue in laying hens associated with thwarted foraging. This controlled study compared the effect in intact and beak-trimmed pullets of providing pecking pans to...

Habenicht, L. M., Staley, A. W., Clancy, B. M. et al. 2022. Characterization of a jumping stereotypy in gerbils (Meriones unguiculatus) and assessment of opaque tubing enrichment on stereotypies and breeding. JAALAS 61(2), 149-158.

Mongolian gerbils can develop stereotypic behaviors, including corner digging. At our institution, gerbils also engage in repetitive corner jumping, which we sought to characterize as a potentially novel stereotypy in gerbils. We then attempted to...

Müller, K., Lengheimer, T., Kral-Pointner, J. B. et al. 2022. Exposure to soiled bedding reduces abnormal repetitive behaviors in mice. Frontiers in Behavioral Neuroscience 16, 1062864.

Hygiene management protocols in laboratory mouse husbandries worldwide most commonly employ soiled bedding-exposed sentinel mice to monitor the occurrence of infections in mouse colonies. Using this approach, sentinel mice repeatedly receive a mixture of used...

Nuber, M., Gonzalez-Uarquin, F., Neufurth, M. et al. 2022. Development of a 3D simulator for training the mouse in utero electroporation. PLOS ONE 17(12), e0279004.

In utero electroporation (IUE) requires high-level training in microinjection through the mouse uterine wall into the lateral ventricle of the mouse brain. Training for IUE is currently being performed in live mice as no artificial...

Schwarzer, A., Erhard, M., Schmidt, P. et al. 2022. Effects of stocking rate and environmental enrichment on the ontogeny of pecking behavior of laying hen pullets confined in aviary compartments during the first 4 weeks of life. Animals 12(19), 2639.

The objective of this study was to describe the ontogeny of the severe feather pecking (SFP), gentle feather pecking (GFP), aggressive pecking (AP), and enrichment pecking (EP) of non-beak-trimmed Lohmann Brown (LB)-pullets during the first...

Schwarzer, A., Rauch, E., Bergmann, S. et al. 2022. Risk factors for the occurrence of feather pecking in non-beak-trimmed pullets and laying hens on commercial farms. Applied Sciences 12(19), 9699.

Severe feather pecking (SFP) is a behavioral disorder, for which there are multifactorial reasons. Various aspects of pullet and laying-hen husbandry—including housing conditions, management, feeding, and genetics—must be considered, to prevent negative outcomes, such as...

Petek, M.,Çavuşoğlu, E. 2021. Welfare assessment of two free-range laying hen flocks in Turkey. Journal of Applied Animal Welfare Science 24(1), 56-63.

This study aimed to determine the prevalence of keel bone deviations and feather damage of laying hens in two different free-range housing systems under commercial conditions. Both of the free-range systems had an indoor barn...

Sørensen, D., Cloutier, S., Gaskill, B. (Eds.). 2021. Animal-centric Care and Management - Enhancing Refinement in Biomedical Research. CRC Press, Boca Raton, FL.

The concept of the 3Rs (Refinement, Reduction and Replacement) has been used as a framework for improving the welfare of laboratory animals for the last half century. By establishing an animal-centric view on housing and...

Koch, A. L., Rusnak, M., Peachee, K. et al. 2021. Comparison of the effects of osmotic pump implantation with subcutaneous injection for administration of drugs after total body irradiation in mice. Laboratory Animals 55(2), 142-149.

The increasing potential for radiation exposure from nuclear accidents or terrorist activities has intensified the need to develop pharmacologic countermeasures against injury from total body irradiation (TBI). Many initial experiments to develop and test these...

Grün, S., Damme, K., Müller, M. et al. 2021. Welfare and performance of three turkey breeds—Comparison between infrared beak treatment and natural beak abrasion by pecking on a screed grinding wheel. Animals 11(8), 2395.

Feather pecking and cannibalism are behavioral disorders that cause animal-welfare-relevant and economic problems. To mitigate these problems, the beaks of conventionally reared turkeys are usually already trimmed in the hatcheries. To find an alternative to...

Schwarzer, A., Plattner, C., Bergmann, S. et al. 2021. Feather pecking in non-beak-trimmed and beak-trimmed laying hens on commercial farms with aviaries. Animals 11(11), 3085.

Severe feather pecking (SFP) is a major animal welfare problem in layers. It results in pain and injuries in the affected animal. It was the aim of this study to gain insight into the actual...

Garcia, T., Brown, C., Margolies, D. et al. 2021. Grinding on a last nerve: Attempting to curb food grinding in mice. Laboratory Animal Science Professional 9(6) (November/December), 34-36.

Food grinding, or chewing food without ingestion, is a topic of interest in the laboratory animal community. In addition to increased effort needed to deal with this excess waste and provide suitable microenvironment for animals...

Mellor, E. L., McDonald Kinkaid, H. K., Mendl, M. T. et al. 2021. Nature calls: Intelligence and natural foraging style predict poor welfare in captive parrots. Proceedings of the Royal Society B: Biological Sciences 288(1960), 20211952

Understanding why some species thrive in captivity, while others struggle to adjust, can suggest new ways to improve animal care. Approximately half of all Psittaciformes, a highly threatened order, live in zoos, breeding centres and...

Fangmeier, M. L., Burns, A. L., Melfi, V. A. et al. 2020. Foraging enrichment alleviates oral repetitive behaviors in captive red-tailed black cockatoos (Calyptorhynchus banksii). Zoo Biology 39(1), 3-12.

The relationship between inadequate foraging opportunities and the expression of oral repetitive behaviors has been well documented in many production animal species. However, this relationship has been less-well examined in zoo-housed animals, particularly avian species...

Fijn, L., van der Staay, F., Goerlich-Jansson, V. et al. 2020. Importance of basic research on the causes of feather pecking in relation to welfare. Animals 10(2), 213.

Feather pecking is a prominent issue in the commercial egg industry, associated with economic losses and welfare problems. A non-systematic literature search suggests that studies on feather pecking are predominantly concerned with applied research goals...

Guinebretière, M., Mika, A., Michel, V. et al. 2020. Effects of management strategies on non-beak-trimmed laying hens in furnished cages that were reared in a non-cage system. Animals 10(3), 399.

Beak trimming in laying hens limits the negative consequences of injurious pecking, but could be prohibited by future regulations. This study assessed a combination of management strategies during the rearing period (objects, perches, music, human...

Arrazola, A., Mosco, E., Widowski, T. M. et al. 2020. The effect of alternative feeding strategies during rearing on the behaviour of broiler breeder pullets. Applied Animal Behaviour Science 224, 104929.

Broiler breeders are feed-restricted during rearing to avoid the negative consequences of obesity during lay due to their genetic potential for fast growth rate. Feed restriction leads to chronic hunger, frustration and lack of satiety...

Reese, L., Baumgartner, K., von Fersen, L. et al. 2020. Feather corticosterone measurements of greater flamingos living under different forms of flight restraint. Animals 10(4), 605.

Deflighting zoo birds is a practice that receives increasing criticism due to its presumed incompatibility with animal welfare. To our knowledge, this is the first approach to address this problem in a scientific way. To...