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...

Sen Sarma, O., Frymus, N., Axling, F. et al. 2023. Optimizing zebrafish rearing−Effects of fish density and environmental enrichment. Frontiers in Behavioral Neuroscience 17, 1204021.

Despite its popularity in research, there is very little scientifically validated knowledge about the best practices on zebrafish (Danio rerio) husbandry, which has led to several facilities having their own husbandry protocols. This study was...

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...

Klabukov, I., Shestakova, V., Krasilnikova, O. et al. 2023. Refinement of animal experiments: Replacing traumatic methods of laboratory animal marking with non-invasive alternatives. Animals 13(22), 3452.

Reliable methods for identifying rodents play an important role in ensuring the success of preclinical studies. However, animal identification remains a trivial laboratory routine that is not often discussed, despite the fact that more than...

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...

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”)...

Anderson, M. G., Campbell, A. M., Kuhn, D. D. et al. 2022. Impact of environmental complexity and stocking density on affective states of rainbow trout (Oncorhynchus mykiss). Animal Cognition 25(5), 1331–1343.

Environmental condition, such as environmental complexity or stocking density, can directly or indirectly influence animal emotion and ultimately, affective state. Affective states of animals can be assessed through judgement bias tests, evaluating responses to ambiguous...

Rácz, A., Allan, B., Dwyer, T. et al. 2021. Identification of individual zebrafish (Danio rerio): A refined protocol for VIE tagging whilst considering animal welfare and the principles of the 3Rs. Animals 11(3), 616.

In aquatic ecology, studies have commonly employed a tagging technique known as visible implant elastomer (VIE). This method has not been widely adopted by the zebrafish research community and also lacks refinement with regard to...

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...

Martini, A., Huysseune, A., Witten, P. E. et al. 2021. Plasticity of the skeleton and skeletal deformities in zebrafish (Danio rerio) linked to rearing density. Journal of Fish Biology 98(4), 971-986.

The teleost zebrafish (Danio rerio), an established model for human skeletal diseases, is reared under controlled conditions with defined parameters for temperature and photoperiod. Studies aimed at defining the proper rearing density have been performed...

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...

Andersson, M., Kettunen, P. 2021. Effects of holding density on the welfare of zebrafish: A systematic review. Zebrafish 18(5), 297-306.

The zebrafish is becoming an increasingly popular research animal around the world. Its welfare is affected by an array of environmental factors, such as food access and water quality. Holding density is an important welfare...

Young, T., Whiteside, T., Locklear, J. 2020. What is your tattoo ink telling you? Laboratory Animal Science Professional 8(2) (March/April), 62-65.

Tattooing traumatizes the skin, which can result in microbial infections with the severity ranging from minor to life-threating septicemia. Additionally, the metals in colored tattoo ink are known to cause dermal inflammation in some people...

Talbot, S. R., Biernot, S., Bleich, A. et al. 2020. Defining body-weight reduction as a humane endpoint: A critical appraisal. Laboratory Animals 54(1), 99–110.

In many animal experiments scientists and local authorities define a body-weight reduction of 20% or more as severe suffering and thereby as a potential parameter for humane endpoint decisions. In this study, we evaluated distinct...

Zemanova, M. A. 2020. Towards more compassionate wildlife research through the 3Rs principles: Moving from invasive to noninvasive methods. Wildlife Biology 2020(1), no page numbers.

Research in ecology and wildlife biology remains crucial for increasing our knowledge and improving species management and conservation in the midst of the current biodiversity crisis. However, obtaining information on population status often involves invasive...

Helgers, S., Talbot, S. R., Riedesel, A. K. et al. 2020. Body weight algorithm predicts humane endpoint in an intracranial rat glioma model. Scientific Reports 10, 9020.

Humane endpoint determination is fundamental in animal experimentation. Despite commonly accepted endpoint criteria for intracranial tumour models (20% body weight loss and deteriorated clinical score) some animals still die before being euthanized in current research...

Kennedy, R. J., Evans, D., Allen, M. 2020. Long-term retention of dummy acoustic transmitters in adult brown trout. Journal of Fish Biology 97(4), 1281–1284.

A group of 36 1+ age class Salmo trutta were surgically implanted with dummy acoustic tags and monitored for 370 days. In total 13 tags were expelled throughout the experiment with an overall tag loss...

Do, J. P., Defensor, E. B., Ichim, C. V. et al. 2020. Automated and continuous monitoring of animal welfare through digital alerting. Comparative Medicine 70(4), 313-327.

A primary goal in preclinical animal research is respectful and responsible care aimed toward minimizing stress and discomfort while enhancing collection of accurate and reproducible scientific data. Researchers use hands-on clinical observations and measurements as...

McMurray, C., Allen, N., Hook, S. et al. 2018. I3S software as a refinement technique to identify individuals within a captive Scyliorhinus canula population. Animal Technology and Welfare 17(3), 204-205 (IAT Congress 2018 Poster Presentation).

Demarking individual animals within a group is often required in research. However, the process of invasive tagging induces stress and if a tag becomes detached it may wound the animal and/or prevent identification. Photo identification...

Wolfe, A. M., Rahman, M., McFadden, D. G. et al. 2018. Refinement and successful implementation of a scoring system for myxomatosis in a susceptible rabbit (Oryctolagus cuniculus) model. Comparative Medicine 68(4), 280–285.

Myxoma virus is a member of Leporipoxviridae whose tropism is tightly restricted to lagomorphs. In susceptible Oryctolagus rabbits, the virus causes a highly lethal disease known as myxomatosis, which begins as a localized infection but...

Ruberto, T., Clément, R. J. G., Spinello, C. et al. 2018. The tagging procedure of visible implant elastomers influences zebrafish individual and social behavior. Zebrafish 15(5), 433-444.

One commonly used method to preserve individual identity in the study of social behavior of zebrafish is through silicone-based visible implant elastomers (VIEs), which represent a safe and durable tagging procedure. While the effects of...

Barker, T. H., George, R. P., Howarth, G. S. et al. 2017. Assessment of housing density, space allocation and social hierarchy of laboratory rats on behavioural measures of welfare. PLOS ONE 12(9), e0185135.

Minimum space allowances for laboratory rats are legislated based on weight and stocking rates, with the understanding that increased housing density encourages crowding stress. However, there is little evidence for these recommendations, especially when considering...

Wever, K. E., Geessink, f. J., Brouwer, M. A. E. et al. 2017. A systematic review of discomfort due to toe or ear clipping in laboratory rodents. Laboratory Animals 51(6), 583-600.

Toe clipping and ear clipping (also ear notching or ear punching) are frequently used methods for individual identification of laboratory rodents. These procedures potentially cause severe discomfort, which can reduce animal welfare and distort experimental...

Pinelli, C., Leri, F., Turner, P. 2017. Long term physiologic and behavioural effects of housing density and environmental resource provision for adult male and female Sprague Dawley rats. Animals 7(6), 44.

There is considerable interest in refining laboratory rodent environments to promote animal well-being, as well as research reproducibility. Few studies have evaluated the long term impact of enhancing rodent environments with resources and additional cagemates...

Mortell, D., Moores, S. 2017. Increasing survival rates in the Zebrafish (Zebra danio) at the University of Manchester. Animal Technology and Welfare 16(3), 214-215.

The average survival rate for our Zebrafish (ZF) embryos was 65%. When it was time to create our next generation of Wild Type (WT) (used for embryo production), we decided to run a trial focussing...