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. 
Kranz, V. A., Horback, K. M., Parsons, T. D. et al. 2022. Sow behavior during introduction to a large dynamic group is influenced by familiarity and method. Applied Animal Behaviour Science 250, 105624.

Sows in an extensive setting maintain small, stable matrilineal social groups comprised of familiar, and often genetically related, conspecifics. Providing conditions in an intensive farm setting which allow similar social groups could reduce aggression by...

Parois, S. P., Van Der Zande, L. E., Knol, E. F. et al. 2022. Effects of a multi-suckling system combined with enriched housing post-weaning on response and cognitive resilience to isolation. Frontiers in Veterinary Science 9, 868149.

Improving welfare is still a critical issue in pig husbandry. Upgrades of the housing environment seem to be a promising solution to optimise resilience as a whole, and therefore improve animal welfare. The objective of...

Lee, V. E., Arnott, G., Turner, S. P. 2022. Social behavior in farm animals: Applying fundamental theory to improve animal welfare. Frontiers in Veterinary Science 9, 932217.

A fundamental understanding of behavior is essential to improving the welfare of billions of farm animals around the world. Despite living in an environment managed by humans, farm animals are still capable of making important...

dos Santos Gauy, A. C., Bolognesi, M. C., Gonçalves-de-Freitas, E. 2022. Long-term body tactile stimulation reduces aggression and improves productive performance in Nile tilapia groups. Scientific Reports 12(1), 20239.

One concern of the Anthropocene is the effects of human activities on animal welfare, revealing the urgency to mitigate impacts of rearing environments. Body tactile stimulation (TS), like massage therapy, has emerged as an enrichment...

Camargo-Dos-Santos, B., Bellot, M. S., Guermandi, I. I. et al. 2022. Cannabidiol improves Nile tilapia cichlid fish welfare. Scientific Reports 12(1), 17650.

Cannabidiol (CBD) is a substance derived from Cannabis sativa, widely studied in medicine for controlling neural diseases in humans. Besides the positive effects on humans, it also presents anxiolytic proprieties and decreases aggressiveness and stress...

Chou, J.-Y., Parsons, T. D. 2022. A systematic review of the impact of housing on sow welfare during post-weaning and early pregnancy periods. Frontiers in Veterinary Science 9, 903822.

Breeder animals are an important focus in farm animal welfare assessments as they typically live the longest lives and are at the greatest risk for suffering due to their longevity. For breeding pigs, the time...

Ojelade, O. C., Durosaro, S. O., Akinde, A. O. et al. 2022. Environmental enrichment improves the growth rate, behavioral and physiological response of juveniles of Clarias gariepinus under laboratory conditions. Frontiers in Veterinary Science 9, 980364.

Environmental enrichment (EE) improves the growth rate and welfare of some cultured fishes. However, most cultured fish species are raised in non-enriched housing conditions. Clarias gariepinus is an important commercial fish species, but little is...

Popescu, S., Lazar, E. A., Borda, C. et al. 2022. Changes in management, welfare, emotional satate, and human-related docility in stallions. Animals 12(21), 2981.

Despite an increase in awareness of their essential needs, many stallions continue to be kept in conditions limiting their social interactions and movement. To supplement the studies which highlight the effects of these practices on...

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...

Gilmour, K. M., Bard, B. 2022. Social buffering of the stress response: Insights from fishes. Biology Letters 18(10), 20220332.

Social buffering of stress refers to the effect of a social partner in reducing the cortisol or corticosterone response to a stressor. It has been well studied in mammals, particularly those that form pair bonds...

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...

Norscia, I., Collarini, E.,Cordoni, G. 2021. Anxiety behavior in pigs (Sus scrofa) decreases through affiliation and may anticipate threat. Frontiers in Veterinary Science 8, 630164.

Anxiety is a physio-psychological state anticipating an imminent threat. In social mammals it is behaviorally expressed via displacement activities and buffered via affiliation. Anxiety research on domestic pigs (Sus scrofa) has mostly focused on abnormal/stereotypic...

Camerlink, I., Proßegger, C., Kubala, D. et al. 2021. Keeping littermates together instead of social mixing benefits pig social behaviour and growth post-weaning. Applied Animal Behaviour Science 235, 105230.

The importance of social stability and its influence on the expression of the social behaviour repertoire in domestic animals remains poorly understood, especially for affiliative behaviours and other putative socio-positive behaviours such as social play...

Prior, H., Holbrook, M. 2021. Strategies to encourage the adoption of social housing during cardiovascular telemetry recordings in non-rodents. Journal of Pharmacological and Toxicological Methods 108, 106959.

The National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) is working with industry to promote social housing during cardiovascular telemetry recordings within non-rodent safety pharmacology and toxicology studies. Following surveys...

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...

Gehlen, H., Krumbach, K., Thöne-Reineke, C. 2021. Keeping stallions in groups—Species-appropriate or relevant to animal welfare? Animals 11(5), 1317.

This literature review was aimed at analyzing whether stallion husbandry in groups is possible and desirable or poses risks. This was determined on the basis of different studies in order to be able to give...

Krueger, K., Esch, L., Farmer, K. et al. 2021. Basic needs in horses?—A literature review. Animals 11(6), 1798.

Every animal species has particular environmental requirements that are essential for its welfare, and when these so-called “basic needs” are not fulfilled, the animals suffer. The basic needs of horses have been claimed to be...

Liu, X., Song, P., Yan, H. et al. 2021. Comparison of the behavior, physiology, and offspring resilience of gestating sows when raised in a group housing system and individual stalls. Animals 11(7), 2076.

Being in a confined environment causes chronic stress in gestating sows, which is detrimental for sow health, welfare and, consequently, offspring physiology. This study assessed the health and welfare of gestating sows housed in a...

Ji, W., Bi, Y., Cheng, Z. et al. 2021. Impact of early socialization environment on social behavior, physiology and growth performance of weaned piglets. Applied Animal Behaviour Science 238, 105314.

Weaning and mixing cause substantial social stress among piglets and frequently lead to stress, injury, inflammation, immunosuppression and growth retardation. This study aimed to investigate the effects of different early social environments on social behavior...

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...

Peden, R. S. E., Turner, S. P., Camerlink, I. et al. 2021. An estimation of the financial consequences of reducing pig aggression. PLOS ONE 16(5), e0250556.

Animal welfare scientists have accumulated knowledge and developed interventions to improve livestock welfare, but these are poorly adopted in commercial practice. Animal welfare interventions are rarely tested for economic viability and this limits their uptake...

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)...