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. 
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...

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)...

Morton, D. B. 2023. A model framework for the estimation of animal “suffering”: Its use in predicting and retrospectively assessing the impact of experiments on animals. Animals 13(5), 800.

This paper presents and illustrates, with a working example, a hypothesis for the assessment of ongoing severity before and during an experiment that will enable humane endpoints and intervention points to be applied accurately and...

Ruvira, S., Rodríguez-Rodríguez, P., Cañas, S. et al. 2023. Evaluation of parameters which influence voluntary ingestion of supplements in rats. Animals 13(11), 1827.

Drug safety and efficacy studies frequently use oral gavage, but repetitive usage may cause problems. Administration through voluntary ingestion represents an opportunity for refinement. We aimed to develop a protocol for voluntary ingestion of gelatin-based...

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...

Andersen, I. L., Ocepek, M., Thingnes, S. L. et al. 2023. Welfare and performance of finishing pigs on commercial farms: Associations with group size, floor space per pig and feed type. Applied Animal Behaviour Science 265, 105979.

Based on data from a field survey of 85 Norwegian farms, we aimed to investigate associations of group size, floor space per pig and type of feed with selected welfare- and performance indicators in finishing...

Contreras-Jodar, A., Escribano, D., Cerón, J. J. et al. 2023. Reducing stocking densities and using cooling systems for more adapted pigs to high temperatures when reared in intensive conditions. Animals 13(15), 2424.

This study is aimed at evaluating the effect of reducing stocking density and using cooling systems to mitigate the negative effects of high temperatures in growing pigs (females and castrated males) reared in intensive conditions...

Calisir, M., Yilmaz, O., Kolatan, H. E. et al. 2023. Effects of litter size and caging on physical and mental development in rats. Physiology & Behavior 267, 114200.

As a multidisciplinary field, laboratory animal science promotes or accelerates the emergence of innovative ideas and products. As research has increased, so has the demand for laboratory animals with reliable, standardized characteristics. Thus, the breeding...

Hanh, H. Q., Phuong, N. T., Tien, N. D. et al. 2023. Effects of stocking density in group cages on egg production, profitability, and aggressive pecking of hens. Journal of Applied Animal Welfare Science 26(3), 374–385.

There is an increasing concern about welfare issues related to battery cages, which are commonly used in Vietnam, and requires a modified cage that improves hen welfare while retaining its economic and management advantages. We...

Miguelena Chamorro, B., Swaminathan, G., Mundt, E. et al. 2023. Towards more translatable research: Exploring alternatives to gavage as the oral administration route of vaccines in rodents for improved animal welfare and human relevance. Lab Animal 52(9), 195–197.

Oral vaccines are gaining attention for their ease of administration and ability to activate mucosal immune responses. However, preclinical studies using this route often require the use of gavage, which has limitations. In this comment...

Mocz, F., Michel, V., Janvrot, M. et al. 2022. Positive effects of elevated platforms and straw bales on the welfare of fast-growing broiler chickens reared at two different stocking densities. Animals 12(5), 542.

In conventional rearing systems, fast-growing broiler chickens commonly experience welfare issues, such as contact dermatitis, walking difficulties or a lack of expression of species-specific behaviours. Enriching their environment may be a way to improve their...

Bartlett, J., Davies, J., Purawijaya, D. et al. 2022. Refinement of handling and dosing methods for rats and mice. Animal Technology and Welfare 21(2), 120-124.

Modified Handling for Mice: Handling mice by gripping the base of the tail has been shown to negatively impact animal welfare by increasing anxiety and aversion to handling. We aimed to refi ne the dosing...

Chesler, K. C., Motz, C. T., Bales, K. L. et al. 2022. Voluntary oral dosing for precise experimental compound delivery in adult rats. Laboratory Animals 56(2), 147-156.

Preclinical drug studies routinely administer experimental compounds to animal models with the goal of minimizing potential adverse events from the procedure. In this study, we assessed the ability to train adult male Long Evans rats...

Williams, W. O., Baneux, P. 2022. Humane Intervention Points: Refining endpoint terminology to incorporate non-euthanasia intervention options to improve animal welfare and preserve experimental outcomes. Laboratory Animals 56(5), 482-489.

Consideration of The Three R’s (Replacement, Reduction, and Refinement) is essential when setting Humane Endpoints; however, a common interpretation assumes that Humane Endpoints are timepoints to perform euthanasia. This interpretation is not always consistent with...

Saraiva, J. L., Rachinas-Lopes, P., Arechavala-Lopez, P. 2022. Finding the “golden stocking density”: A balance between fish welfare and farmers’ perspectives. Frontiers in Veterinary Science 9, 930221.

The effects of stocking density on fish welfare are complex and involve many interacting parameters. This complex relationship between fish welfare, stocking density and influencing factors make it challenging to define a specific optimal (“golden”)...

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...

van der Eijk, J. A. J., Gunnink, H., Melis, M. et al. 2022. Reducing stocking density benefits behaviour of fast- and slower-growing broilers. Applied Animal Behaviour Science 257, 105754.

The broiler industry has come under sustained pressure from welfare organizations to improve broiler welfare. Breed and stocking density are important factors for broiler welfare and are often specified as criteria for higher welfare systems...

Stevens, C., Hawkins, P., Smulders, T. V. et al. 2021. Report of the 2020 RSPCA/UFAW rodent and rabbit welfare meeting. Animal Technology and Welfare 20(1), 21-33.

The RSPCA/UFAW rodent and rabbit welfare group has held a one-day meeting every autumn for the last 27 years, so that its members can discuss current welfare research, exchange views on welfare issues and share...

Phillips, H. N., Heins, B. J. 2021. Effects of outdoor stocking density on growth, feather damage and behavior of slow-growing free-range broilers. Animals 11(3), 688.

Access to pasture is a main benefit of free-range broiler housing systems, yet the level of outdoor stocking density on broiler animal welfare remains unsettled. The growth, feather damage, pasture ranging and behaviors were assessed...

Silva-Reis, R., Faustino-Rocha, A. I., Gonçalves, M. et al. 2021. Refinement of animal model of colorectal carcinogenesis through the definition of novel humane endpoints. Animals 11(4), 985.

This study aimed to define appropriate humane endpoints (HEs) for an animal model of colorectal carcinogenesis (CRC). Twenty-nine male Wistar rats were divided into two control groups (CTRL1 and CTRL2) injected with ethylenediamine tetraacetic acid...

Manell, E., Hedenqvist, P., Jensen-Waern, M. 2021. Training pigs for oral glucose tolerance test—Six years’ experience of a refined model. Animals 11(6), 1677.

Animal models of human diseases are important in biomedical research. When using animals for scientific purposes, the 3Rs (replace, reduce, refine) should be considered. Refinement of animal models is essential to ensure best use of...

Nunamaker, E. A., Davis, S., O’Malley, C. I. et al. 2021. Developing recommendations for cumulative endpoints and lifetime use for research animals. Animals 11(7), 2031.

Research animals are important for scientific advancement, and therefore, their long-term welfare needs to be monitored to not only minimize suffering, but to provide positive affective states and experiences. Currently, there is limited guidance in...

Ellis, T., Katsiadaki, I. 2021. Clarification of early end-points for refinement of animal experiments, with specific reference to fish. Laboratory Animals 55(3), 244-253.

Appropriate end-points are integral to the refinement of laboratory animal experiments. Our recent experience has highlighted that ambiguity around end-points is hampering their adoption in experiments that cause severe suffering to fish. In toxicology, the...

Satokar, V., Vickers, M., Bridge-Comer, P. et al. 2021. Emulsified gels: A refined vehicle for accurate and rapid oral administration of lipid based preparations to rats. Animal Technology and Welfare 20(2), 95-103.

Oro-gastric gavage is used to accurately administer nutritional substances or drugs to animals. However, it induces stress and has a substantial risk of mishap. Incorporation into edible gels is difficult for lipid-based preparations. We report...

Anderson, M. G., Campbell, A. M., Crump, A. et al. 2021. Effect of environmental complexity and stocking density on fear and anxiety in broiler chickens. Animals 11(8), 2383.

Barren housing and high stocking densities may contribute to negative affective states in broiler chickens, reducing their welfare. We investigated the effects of environmental complexity and stocking density on broilers’ attention bias (measure of anxiety)...