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)...

Brando, S., Norman, M. 2023. Handling and training of wild animals: Evidence and ethics-based approaches and best practices in the modern zoo. Animals 13(14), 2247.

There is an ethical responsibility to provide all animals living in human care with optimal and positive well-being. As animals living in zoos and aquariums frequently interact with their human caregivers as part of their...

Mählis, G., Kleine, A., Lüschow, D. et al. 2023. Clicker training as an applied refinement measure in chickens. Animals 13(24), 3836.

When using chickens in animal studies, the handling of these animals for sample collection or general examinations is considered stressful due to their prey nature. For the study presented here, plasma and salivary corticosterone as...

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...

Slocum, S. K., Morris, K. L. 2022. Assessing preference in a paired-stimulus arrangement with captive vultures (Aegypius monachus). Journal of Applied Animal Welfare Science 25(4), 362-367.

Vultures play an important role in our ecosystem by filtering out bacteria and viruses harmful to humans (e.g., rabies, botulism). However, many vultures remain in human care due to skill deficits and behavioral excesses, which...

Prentice, P. M., Houslay, T. M., Wilson, A. J. 2022. Exploiting animal personality to reduce chronic stress in captive fish populations. Frontiers in Veterinary Science 9, 1046205.

Chronic stress is a major source of welfare problems in many captive populations, including fishes. While we have long known that chronic stress effects arise from maladaptive expression of acute stress response pathways, predicting where...

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...

Torgerson-White, L., Sánchez-Suárez, W. 2022. Looking beyond the shoal: Fish welfare as an individual attribute. Animals 12(19), 2592.

Welfare is an individual attribute. In general, providing captive nonhuman animals with conditions conducive to good welfare is an idea more easily applied when dealing with few individuals. However, this becomes much harder—if not impossible—under...

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...

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...

Sørensen, D., Cloutier, S., Gaskill, B. (Eds.). 2021. Animal-centric Care and Management - Enhancing Refinement in Biomedical Research. CRC Press, Boca Raton, FL.

The concept of the 3Rs (Refinement, Reduction and Replacement) has been used as a framework for improving the welfare of laboratory animals for the last half century. By establishing an animal-centric view on housing and...

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...

Huber, N., Mahr, K., Tóth, Z. et al. 2021. The stressed bird in the hand: Influence of sampling design on the physiological stress response in a free-living songbird. Physiology & Behavior 238, 113488.

Despite the widely used application of standardized capture-handling protocols to collect blood and assess the physiological stress response, the actual sampling design (e.g., timing and the number of blood samples) often differs between studies, and...

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)...

Forslind, S., Blokhuis, H. J., Riber, A. B. 2021. Disturbance of resting behaviour of broilers under different environmental conditions. Applied Animal Behaviour Science 242, 105425.

Resting behaviours make up a large part of the daily time budget of broilers. However, in intensive broiler production systems disruptions of resting behaviours occur, where resting individuals get disturbed by active individuals. Such interruptions...

de A. P. Ramos, G., de Azevedo, C. S., Jardim, T. H. A. et al. 2021. Temperament in captivity, environmental enrichment, flight ability, and response to humans in an endangered parrot species. Journal of Applied Animal Welfare Science 24(4), 379-391.

Temperament assessment is useful in reintroduction programs. Reactivity to humans and flight ability are also important behavioral aspects for captive parrots candidates to reintroduction. The study aimed: a) to evaluate if behavioral responses to environmental...

Melfi, V. A., Dorey, N. R., Ward, S. (Eds.) 2020. Zoo Animal Learning and Training. John Wiley & Sons: Hoboken, NJ, 384 pp.

Comprehensively explains animal learning theories and current best practices in animal training within zoos. This accessible, up-to-date book on animal training in a zoo/aquaria context provides a unified approach to zoo animal learning, bringing together...

Glaspell, S. 2020. Flight to freedom: Behavior modification of an undomesticated pigeon using human interaction. Laboratory Animal Science Professional 8(2) (March/April), 58-61.

The white-crowned pigeon, Patagioenas leucocephala, is a species of bird not often used in research. This may be related to its anxiety during normal human interactions, such as with cage changing. Our institution acquired a...

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...

Reinhardt, V. (ed.) 2020. It’s Okay to Cry - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume V. Animal Welfare Institute, Washington, DC.

This is the 5th volume of selected discussions that took place on the electronic Laboratory Animal Refinement & Enrichment Forum between February 2016 and December 2019. The forum was created in October 2002; it allows...

Estien, C., O’Connell, C., Francis, X. et al. 2020. Temporary behavioral responses to playbacks by a pest parrot and implications for management. Animal Behavior and Cognition 9(4), 363–384.

Human-wildlife interactions continue to increase due to anthropogenic disturbances, with some interactions resulting in conflict. Leveraging a taxa’s bias for a particular sensory cue is a promising management avenue for reducing the potential and realized...

Pedersen, I. J., Forkman, B. 2019. Improving leg health in broiler chickens: A systematic review of the effect of environmental enrichment. Animal Welfare 28(2), 215-230.

Leg problems are highly prevalent in modern broiler production and provision of environmental enrichment could be a strategy to improve leg health. Different types of environmental enrichment have undergone evaluation. Our objective was to conduct...

Stevens, C., Hawkins, P., Lovell-Badge, R. et al. 2019. Report of the 2018 RSPCA/UFAW Rodent and Rabbit Welfare Group meeting. Animal Technology and Welfare 18(2), 81-91.

The RSPCA/UFAW Rodent (and now Rabbit) Working Group has held a one-day meeting every autumn for the last 25 years, so that its members can discuss current welfare research, exchange views on welfare issues and...