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...

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...

Meira, J. E. S., Nogueira-Filho, S. L. G., Mendl, M. et al. 2023. Responses to environmental enrichment are associated with personality characteristics in chestnut-bellied seed finches (Sporophila angolensis). Behavioural Processes 204, 104801.

Environmental enrichment (EE) is used to promote natural behaviours in captive animals and may hold promise as a form of pre-release training, a strategy for improving coping skills of translocated birds. We investigated the use...

Bini de Lima, A. C., Sebastião da Fé, V. C., Palermo Hernandes, M. S. et al. 2023. Olfactory stimulation as environmental enrichment for domestic horses—A review. Animals 13(20), 3180

Horses constantly face several challenges inherent to the domestic environment, and it is common for the expression of their natural behavior to be drastically limited. Environmental enrichment has been suggested as an alternative to improve...

Fernández-Lázaro, G., Latorre, R., Fontanillas Pérez, J. C. et al. 2023. Reaction to novel objects and fecal glucocorticoid metabolite levels in two species of nocturnal geckos. Animals 13(21), 3384.

Many reptiles are maintained in captivity and heavily traded, although welfare measures for many species are not well established and are under-researched compared to other animals. In this study, we focused on two of these...

Gueguen, L., Henry, S., Delbos, M. et al. 2023. Selected acoustic frequencies have a positive impact on behavioural and physiological welfare indicators in thoroughbred racehorses. Animals 13(18), 2970.

(1) Background: Since antiquity, it is considered that sounds influence human emotional states and health. Acoustic enrichment has also been proposed for domestic animals. However, in both humans and animals, effects vary according to the...

Krönke, F., Xu, L. 2023. Sensory stimulation as a means of sustained enhancement of well-being in leopard geckos, Eublepharis macularius (Eublepharidae, Squamata). Animals 13(23), 3595.

Although the private keeping of reptiles has boomed in most western countries since the millennium, studies dealing with the recognition and promotion of welfare in these reptiles seem to represent a blind spot of scientific...

Lansade, L., Lemarchand, J., Reigner, F. et al. 2022. Automatic brushes induce positive emotions and foster positive social interactions in group-housed horses. Applied Animal Behaviour Science 246, 105538.

In mammals, positive tactile contact is recognized as an effective tool for triggering positive affective states. In this study, we investigated the benefits of providing automatic rotative brushes for group-housed horses. Our three aims were...

Spitzer, H. B., Meagher, R. K., Proudfoot, K. L. 2022. The impact of providing hiding spaces to farmed animals: A scoping review. PLOS ONE 17(11), e0277665.

Many wild animals perform hiding behaviours for a variety of reasons, such as evading predators or other conspecifics. Unlike their wild counterparts, farmed animals often live in relatively barren environments without the opportunity to hide...

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”)...

Howard, D., Freeman, M. S. 2022. Overlooked and under-studied: A review of evidence-based enrichment in varanidae. Journal of Zoological and Botanical Gardens 3(1), 32–43.

Enrichment has become a key aspect of captive husbandry practices as a means of improving animal welfare by increasing environmental stimuli. However, the enrichment methods that are most effective varies both between and within species...

Alnes, I. B., Jensen, K. H., Skorping, A. et al. 2021. Ontogenetic change in behavioral responses to structural enrichment from fry to parr in juvenile Atlantic salmon (Salmo salar L.). Frontiers in Veterinary Science 8, 638888.

Enrichment is widely used as a tool for studying how changes in environment affect animal behavior. Here, we report an experimental study investigating if behaviors shaped by stimuli from environmental enrichment depending on the stage...

Lambert, K. 2021. DIY: Dehydrated watermelon training chips. Laboratory Animal Science Professional 9(4) (July/August), 48.

This simple DIY training treat is great for NHP, swine, rabbits, rodents, and dogs. Note that dehydrated watermelon may resemble muscle tissue!

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...

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...

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...

Raspa, F., Tarantola, M., Bergero, D. et al. 2020. Stocking density affects welfare indicators in horses reared for meat production. Animals 10(6), 1103.

Horses kept for meat production are reared in intensive breeding farms. We employed a checklist adapted from the Animal Welfare Indicators (AWIN) assessment protocol. Our evaluation aims to assess whether welfare indicators are influenced by...

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...

Gomes Correa, M., Ferreira Rodrigues e Silva, C., Antunes Dias, L. et al. 2020. Welfare benefits after the implementation of slow-feeder hay bags for stabled horses. Journal of Veterinary Behavior 38, 61-66.

Horse confinement is a common practice worldwide. However, preventing horses from grazing and denying them social interaction can compromise their welfare and lead to undesirable consequences. Considering the hypothesis that increasing the forage consumption time...

Raspa, F., Tarantola, M., Bergero, D. et al. 2020. Time-budget of horses reared for meat production: Influence of stocking density on behavioural activities and subsequent welfare. Animals 10(8), 1334.

Horses reared for meat production can be kept in intensive breeding farms where they are housed in group pens at high stocking densities. The present study aimed to evaluate whether the expressed behaviours correlated with...

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.

Euet, A., Lemarchand, J., Parias, C., Mach, N. et al. 2019. Housing horses in individual boxes is a challenge with regard to welfare. Animals 9(9), 621.

Horses are mainly housed in individual boxes. This housing system is reported to be highly detrimental with regard to welfare and could trigger the expression of four behavioural indicators of a compromised welfare state: stereotypies...

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...

Proops, L. Osthaus, B., Bell, N. et al. 2019. Shelter-seeking behavior of donkeys and horses in a temperate climate. Journal of Veterinary Behavior 32, 16-23.

Domestic donkeys descended from wild asses, adapted to the semi-arid climates of Africa, whereas domestic horses originate from more temperate areas of Eurasia. Despite this difference in evolutionary history, modern domestic equids can be found...