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)...

Marks, C. A., Allen, L., Lindeberg, H. 2023. Non-lethal dose-response models replace lethal bioassays for predicting the hazard of para-animopropiophenone to Australian wildlife. Animals 13(3), 472.

Para-aminopropiophenone (PAPP) is a potent methaemoglobin (MetHb) forming agent used for the lethal control of exotic carnivores and mustelids. To assess the sensitivity of Australian wildlife to PAPP we developed an in vivo assay that...

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...

Warwick, C., Pilny, A., Steedman, C. et al. 2023. Mobile zoos and other itinerant animal handling events: Current status and recommendations for future policies. Animals 13(2), 214.

Mobile zoos are events in which non-domesticated (exotic) and domesticated species are transported to venues such as schools, hospitals, parties, and community centres, for the purposes of education, entertainment, or social and therapeutic assistance. We...

Williams, E., Hunton, V., Hosey, G. et al. 2023. The impact of visitors on non-primate species in zoos: A quantitative review. Animals 13(7), 1178.

Visitors are a prominent feature in the lives of zoo animals, and their presence can cause a range of impacts on zoo animals (typically classed as positive, negative or neutral impacts), commonly referred to as...

Bertin, A., Mulot, B., Nowak, R. et al. 2023. Captive blue-and-yellow macaws (Ara ararauna) show facial indicators of positive affect when reunited with their caregiver. Behavioural Processes 206, 104833.

In mammals, human-animal bonding is recognized as a source of positive affect for companion or farm animals. Because this remains unexplored in birds, we investigated captive parrots’ perspective of the human-animal relationship. We used a...

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...

Taylor, P. S., Hemsworth, P. H., Rault, J.-L. 2022. Environmental complexity: Additional human visual contact reduced meat chickens’ fear of humans and physical items altered pecking behavior. Animals 12(3), 310.

Increased environmental complexity can improve animal welfare, depending on the resources provided and use by the animal. We provided chickens either with physical items that posed no biosecurity risk and were inexpensive (balls, chains, perches...

Acharya, R. Y., Hemsworth, P. H., Coleman, G. J. et al. 2022. The animal-human interface in farm animal production: Animal fear, stress, reproduction and welfare. Animals 12(4), 487.

A negative human-animal relationship (HAR) from the perspective of the animal is a limiting factor affecting farm animal welfare, as well as farm animal productivity. Research in farm animals has elucidated sequential relationships between stockperson...

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...

Celozzi, S., Battini, M., Prato-Previde, E. et al. 2022. Humans and goats: Improving knowledge for a better relationship. Animals 12(6), 774.

There is consensus that the quality of the human–animal relationship (HAR) is relevant to guarantee appropriate levels of animal welfare. Given the impact that HAR may have on both goats and human beings, the aim...

Mitin, H., Zulkifli, I., Che Jamri, M. H. et al. 2022. Alleviation of catching and crating stress by dietary supplementation of Bacillus subtilis in Pekin ducks. Animals 12(24), 3479.

Catching and crating may elicit stress and fear reactions in poultry because the procedures involve human contact and exposure to a novel environment. This study determined the effects of dietary probiotic supplementation on physiological stress...

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...

Wilson, C. H., Wyeth, R. C., Spicer, J. I. et al. 2022. Effect of animal stocking density and habitat enrichment on survival and vitality of wild green shore crabs, Carcinus maenas, maintained in the laboratory. Animals 12(21), 2970.

The wide geographic distribution, large size and ease of capture has led to decapod crustaceans being used extensively in laboratory experiments. Recently in the United Kingdom decapod crustaceans were listed as sentient beings, resulting in...

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...

Gresham, C., Mathews, F., Ferguson, A. et al. 2022. Does handling for public talks in zoos affect the behaviour of captive Mexican red-kneed spiders Brachypelma hamorii? Journal of Zoological and Botanical Gardens 3(2), 158–169.

Zoos include invertebrates in visitor interaction sessions to educate and spread conservation messages to the public. Yet, the welfare implications of these encounters on invertebrates are unstudied. Empirical studies reveal negative effects of handling on...

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...

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...

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...