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...

Ermers, C., McGilchrist, N., Fenner, K. et al. 2023. The fibre requirements of horses and the consequences and causes of failure to meet them. Animals 13(8), 1414.

Failure to meet the minimum forage requirement of 1.5% of the horse’s bodyweight and the opportunity for foraging for a minimum of 8 h a day (not going without this opportunity longer than four to...

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)...

Seck, M., Jobling, R., Brown, A. F. 2023. Trialling locally made, low-cost bits to improve bit-related welfare problems in cart horses: Findings from a study in Senegal. Animals 13(1), 2.

Bits used for cart horses in Senegal are typically made of recovered construction iron and often have defects related to design, shape, fit and metal quality. Consequently, there is widespread presence of bit-related oral injury...

Goodenough, A. E., Sewell, A., McDonald, K. 2023. Behavioural patterns in zoo-housed Humboldt penguins (Spheniscus humboldti) revealed using long-term keeper-collected data: Validation of approaches and improved husbandry. Applied Animal Behaviour Science 258, 105811.

Given the increasing obligation to elevate animal welfare beyond minimum expectations, zoos need robust mechanisms to monitor physical activity and species-appropriate behaviours. This is not without challenge as animal behaviour can vary seasonally or be...

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...

O’Brien, S. L., Cronin, K. A. 2023. The impacts of a commercial bubble curtain on zoo-housed African penguin (Spheniscus demersus) swimming behavior. Journal of Zoological and Botanical Gardens 4(3), 567–577.

Swimming is an important behavior for all penguin species. However, zoo-housed penguins typically do not swim as often as their wild counterparts, which may have consequences for their health and welfare. In an effort to...

Putyora, E., Brocklehurst, S., Sandilands, V. 2023. The effects of commercially-relevant disturbances on sleep behaviour in laying hens. Animals 13(19), 3105.

Ensuring the welfare of commercially kept animals is a legal and ethical responsibility. Sleep behaviour can be sensitive to environmental perturbations and may be useful in assessing welfare state. The objective of this study was...

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...

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...

Eisenbeiser, S., Serbe-Kamp, É., Gage, G. J. et al. 2022. Gills just want to have fun: Can fish play games, just like us? Animals 12(13), 1684.

It is common to observe play in dogs, cats, and birds, but have we been ignoring play in one of the most common house pets of all… fish? Aquarium fish are often used as meditative...

Rose, P., Roper, A., Banks, S. et al. 2022. Evaluation of the time-activity budgets of captive ducks (Anatidae) compared to wild counterparts. Applied Animal Behaviour Science 251, 105626.

Ducks are commonly housed in captive environments where their abilities for flight are constrained, either temporarily or permanently. The use of flight restraint in modern animal management is contentious and ethically questioned yet any associated...

Abazaris, J., Hashway, S. 2022. Vole husbandry at Colorado University Boulder. Laboratory Animal Science Professional 10(4) (July/August), 12-15.

Since they arrived at CU Boulder, we have learned a lot about the voles from the laboratory, other institutions, and our trial-and-error. We hope this information can be helpful to any considering adding voles to...

Adams, C. R., Park, T. J. 2022. The husbandry and management of naked mole-rats (Heterocephalus glaber). Laboratory Animal Science Professional 10(4) (July/August), 16-18.

Naked mole-rats (NMRs) have unique husbandry requirements that need to be considered when maintaining them in captivity. We have successfully maintained NMRs at the University of Illinois at Chicago for more than 20 years. This...

Houstin, A., Zitterbart, D. P., Winterl, A. et al. 2022. Biologging of emperor penguins—Attachment techniques and associated deployment performance. PLOS ONE 17(8), e0265849.

An increasing number of marine animals are equipped with biologgers, to study their physiology, behaviour and ecology, often for conservation purposes. To minimise the impacts of biologgers on the animals’ welfare, the Refinement principle from...

Greening, L., McBride, S. 2022. A review of equine sleep: Implications for equine welfare. Frontiers in Veterinary Science 9, 916737.

Sleep is a significant biological requirement for all living mammals due to its restorative properties and its cognitive role in memory consolidation. Sleep is ubiquitous amongst all mammals but sleep profiles differ between species dependent...

Munday, C., Rose, P. 2022. Envirionmental and social influences on the behaviour of free-living mandarin ducks in richmond park. Animals 12(19), 2554.

Many species of birds are housed in zoos globally and are some of the most popular of animals kept under human care. Careful observations of how species live and behave in their natural habitats can...

Ruet, A., Arnould, C., Lemarchand, J. et al. 2022. Horse welfare: A joint assessment of four categories of behavioural indicators using the AWIN protocol, scan sampling and surveys. Animal Welfare 31(4), 455–466.

Domesticated horses (Equus caballus) can be exposed to a compromised welfare state and detecting a deterioration in welfare is essential to modify the animals’ living conditions appropriately. This study focused on four categories of behavioural...

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...

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...

Barretta, L. A., Maloney, S. K., Blachea, D. 2021. Pekin ducks are motivated to access their nest site and exhibit a stress-induced hyperthermia when unable to do so. Animal 15(1), 100067.

The origins of floor-laying in ducks could be low motivation for a nest, or stress related to difficulties with accessing a nest (e.g. competition). Using a behavioural demand test, we investigated if increasing the work...

Coleman, K., Shapiro, S. J. (Eds.). 2021. Behavioral Biology of Laboratory Animals (1st ed). CRC Press, Boca Raton, FL.

This 30-chapter volume informs students and professionals about the behavioral biology of animals commonly housed in laboratory and other captive settings. Each species evolved under specific environmental conditions, resulting in unique behavioral patterns, many of...