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. 
DePasquale, C., Kemerer, N., White, N. et al. 2021. The influence of an enriched environment in enhancing recognition memory in zebrafish (Danio rerio). Frontiers in Veterinary Science 8, 749746.

Environmental enrichment is used to increase social and physical stimulation for animals in captivity which can lead to enhanced cognition. Fundamental to the positive effect enrichment has on the brain is that it provides opportunities...

da Silva Medeiros Elidio, H., Coelho, J. W. R., Cavalcanti Pereira da Silva, L. C. et al. 2021. Housing density and aggression in Syrian hamsters. JAALAS 60(5), 506-509.

The Syrian hamster (Mesocricetus auratus) is a solitary and naturally territorial animal, with female hamsters being more aggressive than males. This behavior makes handling difficult because they are usually housed in groups, which can lead...

Jones, N. A. R., Webster, M. M., Salvanes, A. G. V. 2021. Physical enrichment research for captive fish: Time to focus on the DETAILS. Journal of Fish Biology 99(3), 704-725.

Growing research effort has shown that physical enrichment (PE) can improve fish welfare and research validity. However, the inclusion of PE does not always result in positive effects and conflicting findings have highlighted the many...

Brandão, M. L., Dorigão-Guimarães, F., Bolognesi, M. C. et al. 2021. Understanding behaviour to improve the welfare of an ornamental fish. Journal of Fish Biology 99(3), 726-739.

Some common practices in aquaculture, ornamental trade and fish facilities may disturb the behavioural repertoire of fish and its natural adaptive value, reducing welfare and impairing fish production. Hence, it is necessary to understand fish...

Monreal-Pawlowsky, T., Vaicekauskaitė , R., Palencia Membrive, G. et al. 2021. Goal-oriented behavioural and environmental enrichment in aquarium species. Journal of Zoo and Aquarium Research, 9(4), 273-280.

Environmental enrichment is a common tool used in zoo and aquarium settings to provide mental and physical stimulation to animals under human care. This paper aims to present a primary approach to goal-oriented environmental and...

Janhunen, M., Piironen, J., Vainikka, A. et al. 2021. The effects of environmental enrichment on hatchery-performance, smolt migration and capture rates in landlocked Atlantic salmon. PLOS ONE 16(12), e0260944.

Enrichment of rearing environment with natural elements has been suggested to improve the welfare and post-release survival of cultured fish. We studied the combined effects of shelter structures, periodical water flow and water level changes...

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...

Waterman, J. O., McNally, R., Harrold, D. et al. 2021. Evaluating environmental enrichment methods in three zoo-housed varanidae lizard species. Journal of Zoological and Botanical Gardens 2(4), 716–727.

Environmental enrichment has been shown to enhance the behavioural repertoire and reduce the occurrence of abnormal behaviours, particularly in zoo-housed mammals. However, evidence of its effectiveness in reptiles is lacking. Previously, it was believed that...

da Silva, A., Lima, M. R., Meletti, P. C. et al. 2020. Impact of environmental enrichment and social group size in the aggressiveness and foraging activity of Serrapinnus notomelas. Applied Animal Behaviour Science 224, 104943.

Fish are widely used in scientific research, and many species are bred for ornamental purposes and human consumption. Despite the large number of fish kept in captivity, research on the welfare of these animals has...

Watson, H. A study into viable wooden enrichment objects for Syrian hamsters. Animal Technology and Welfare 19(1), 86-88.

Failing to provide hamsters with a method to wear down their teeth can lead to detrimental behaviour such as bar chewing, and health issues, for example, overgrown teeth and tooth loss. However, hamsters use their...

Mendonça Soares, S., Kirsten, K., Pompermaier, A. et al. 2020. Sex segregation affects exploratory and social behaviors of zebrafish according to controlled housing conditions. Physiology & Behavior 222, 112944.

Zebrafish has become an animal model in research and articles have established ideal conditions for their maintenance. However, little is known regarding the influence of gender and other cues on zebrafish behavior. Thus, here we...

Arechavala-Lopez, P., Caballero-Froilán, J. C., Jiménez-García, M. et al. 2020. Enriched environments enhance cognition, exploratory behaviour and brain physiological functions of Sparus aurata. Scientific Reports 10, 11252.

Environmental enrichment is considered as a recommended tool to guarantee or improve the welfare of captive fish. This study demonstrates for the first time that structural environmental enrichment enhances cognition, exploratory behaviour and brain physiological...

Krueger, L. D., Thurston, S. E., Kirk, J. et al. 2020. Enrichment preferences of singly housed zebrafish (Danio rerio). JAALAS 59(2), 148–155.

Despite the increasing popularity of zebrafish (Danio rerio) as an animal model, the environmental enrichment preferences of this species have been largely unexplored. We sought to determine the preferences of mature female zebrafish that were...

Thoré, E. S. J., Brendonck, L., Pinceel, T. 2020. Conspecific density and environmental complexity impact behaviour of turquoise killifish (Nothobranchius furzeri). Fish Biology 97(5), 1448–1461.

Fish models are essential for research in many biological and medical disciplines. With a typical lifespan of only 6 months, the turquoise killifish (Nothobranchius furzeri) was recently established as a time- and cost-efficient model to...

Tan, S. L. T., Handasyde, K. A., Rault, J.-L. et al. 2020. Insensitivity to reward shifts in zebrafish (Danio rerio) and implications for assessing affective states. Animal Cognition 23(1), 87–100

Theory and empirical findings predict that individuals in a negative affective state are more sensitive to unexpected reward loss and less sensitive to unexpected reward gain compared to individuals in a neutral or positive affective...

Bolognesi, M. C., dos Santos Gauy, A. C., Gonçalves-de-Freitas, E. 2019. Tactile stimulation reduces aggressiveness but does not lower stress in a territorial fish. Scientific Reports 9, 40.

Body tactile stimulation has a positive effect upon highly social animals, such as mammals and cleaner-client coral-reef fish, by relieving stress and improving health. Conversely, some tactile contacts are naturally detrimental, such as those resulted...

Eagan, T. 2019. Evaluation of enrichment for reptiles in zoos. Journal of Applied Animal Welfare Science 22(1), 69-77.

Studies on environmental enrichment for reptiles are lacking in the scientific literature. Although the literature reflects a limited take on reptile enrichment in the zoological community, it may not be the case in reality as...

Arechavala-Lopez, P., Saraiva, J. L. 2019. Welfare of Cultured and Experimental Fishes. Basel, Switzerland: MDPI, 132 pages.

This open access book is a printed edition of the Special Issue on Welfare of Cultured and Experimental Fishes that was published in the journal Fishes. The PDF is free for download.

Woodward, M. A., Winder, L. A., Watt, P. J. 2019. Enrichment increases aggression in zebrafish. Fishes 4(1), 22.

Environmental enrichment, or the enhancement of an animal’s surroundings when in captivity to maximise its wellbeing, has been increasingly applied to fish species, particularly those used commercially. Laboratory species could also benefit from enrichment, but...

DePasquale, C., Fettrow, S., Sturgill, J. et al. 2019. The impact of flow and physical enrichment on preferences in zebrafish. Applied Animal Behaviour Science 215, 77-81.

Environmental enrichment is used extensively to improve the welfare of animals in captivity, however, the importance of physical exercise as enrichment is only now coming to light. A key question in assessing the welfare of...

Zhang, Z., Zhang, X., Li, Z. et al. 2019. Effects of different levels of environmental enrichment on the sheltering behaviors, brain development and cortisol levels of black rockfish Sebastes schlegelii. Applied Animal Behaviour Science 218, 104825.

Environmental enrichment is a promising way to increase the fitness and survival of fish released for stock enhancement and biological conservation programs. However, the effects of enrichment in different studies on the fish behavior, physiology...

Lee, C. J., Paull, G. C., Tyler, C. R. 2019. Effects of environmental enrichment on survivorship, growth, sex ratio and behaviour in laboratory maintained zebrafish Danio rerio. Journal of Fish Biology 94(1), 86-95.

Environmental enrichment involves increasing the complexity of a fish's environment in order to improve welfare. Researchers are legally obliged to consider the welfare of laboratory animals and poor welfare may result in less robust data...

Solås, M. R., Skoglund, H., Salvanes, A. G. V. 2019. Can structural enrichment reduce predation mortality and increase recaptures of hatchery-reared Atlantic salmon Salmo salar L. fry released into the wild? Journal of Fish Biology 95(2), 575-588.

Captive-reared fish often have poor survival in the wild and may fail to boost threatened populations. Enrichment during the nursery period can in some circumstances generate a broader behavioural repertoire than conventional hatchery production. Yet...

Watz, J. 2019. Structural complexity in the hatchery rearing environment affects activity, resting metabolic rate and post-release behaviour in brown trout Salmo trutta. Journal of Fish Biology 95(2), 638-641.

The effects of structural enrichment in the hatchery rearing environment of brown trout Salmo trutta was linked to post-release performance. Enrichment resulted in reduced swimming activity scored in an open field test and reduced movement...

Jones, N. A. R., Spence, R., Jones, F. A. M. et al. 2019. Shade as enrichment: Testing preferences for shelter in two model fish species. Journal of Fish Biology 95(4), 1161-1165.

We compared preferences shown by zebrafish (Danio rerio) and three-spined stickleback (Gasterosteus aculeatus) for shelter provided by above-tank shade and artificial plants. Zebrafish showed no preference for either shelter, whereas sticklebacks showed a preference for...