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. 
Alig, B. N., Ferket, P. R., Malheiros, R. D. et al. 2023. The effect of housing environment on commercial brown egg layer production, USDA grade and USDA size distribution. Animals 13(4), 694

Consumer demand for retail cage-free eggs is driving the layer industry towards greater use of extensive housing environments. However, there is limited research on how these environments affect egg production characteristics of brown egg layers...

Corsetti, S., Natoli, E., Palme, R. et al. 2023. Instraspecific interactions decrease stress affecting welfare in shelter dogs: A comparison of four different housing conditions. Animals 13(11), 1828.

Shelters are stressful environments for domestic dogs (Canis familiaris). Evaluating dogs’ welfare is crucial to improve their life condition and to promote a better management of shelters. We aimed at verifying which variables improved welfare...

da Silva, M. I. L., Paz, I. C. de L. A., Jacinto, A. S. et al. 2023. Providing environmental enrichments can reduce subclinical spondylolisthesis prevalence without affecting performance in broiler chickens. PLOS ONE 18(4), e0284087.

Environmental enrichment can increase the occurrence of natural behavior and improve leg health and other animal welfare outcomes in broiler chickens. This study aimed to assess the effects of three environmental enrichments, specifically hay bales...

Dare, P., Strasser, R. 2023. Ruff morning? The use of environmental enrichment during an acute stressor in kenneled shelter dogs. Animals 13(9), 1506.

The length of stay for some animals has increased with the recent reduction of animals euthanized in US shelters and animal control facilities. Research examining the effectiveness of different types of enrichment on buffering the...

Dong, Y., Fraley, G. S., Siegford, J. M. et al. 2023. Comparing different environmental enrichments for improving the welfare and walking ability of male turkeys. PLOS ONE 18(5), e0285347.

This study investigated age-related changes in turkey welfare measures (wounds, feather quality (FQ), feather cleanliness, and footpad condition (FCON)) and walking ability (gait) as influenced by different types of environmental enrichment (EE). Tom turkeys (n...

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)...

Kaiser, S., Korte, A., Wistuba, J. et al. 2023. Effects of castration and sterilization on baseline and response levels of cortisol—A case study in male guinea pigs. Frontiers in Veterinary Science 9, 1093157.

An uncontrolled reproduction of animals in human hands should be avoided. To meet this goal, animals are widely castrated, i.e., the gonads are completely removed. Since the gonads are the most important source of sex...

Lee, G.-H., Jo, W., Kang, T.-K. et al. 2023. Assessment of stress caused by environmental changes for improving the welfare of laboratory beagle dogs. Animals 13(6), 1095.

Animal stress is influenced by environmental factors, yet only a few studies have evaluated the effects of environmental stress on captive dogs. This study aimed to evaluate the effects of environmental and social enrichment on...

Pennington, E., Springer, C., Albright, J. et al. 2023. Evaluation of different methods of environmental enrichment to control anxiety in dogs undergoing hemilaminectomy after acute intervertebral disc extrusion: A randomized double-blinded study. Frontiers in Veterinary Science 10, 1124982.

The goal of this randomized, double-blinded, placebo-controlled study was to evaluate the effect of environmental enrichment (EE) on post-operative pain and anxiety in dogs following hemilaminectomy for acute intervertebral disc extrusion (IVDE).MethodsTwenty healthy client-owned dogs...

Pereira, E., Nääs, I. de A., Ivale, A. H. et al. 2023. Energy assessment from broiler chicks’ vocalization might help improve welfare and production. Animals 13(1), 15.

Vocalization seems to be a viable source of signal for assessing broiler welfare. However, it may require an understanding of the birds’ signals, both quantitatively and qualitatively. The delivery of calls with a specific set...

Skånberg, L., Newberry, R. C., Estevez, I. et al. 2023. Environmental change or choice during early rearing improves behavioural adaptability in laying hen chicks. Scientific Reports 13(1), 6178.

Laying hens are typically moved to a novel environment after rearing, requiring adaptability to cope with change. We hypothesized that the standard rearing of laying hen chicks, in non-changing environments with limited choices (a single...

Kapusta, J., Siewierska, D., Kruczek, M. et al. 2023. Species specific differences in short-term behavioral reaction of voles to cage elements removal. Applied Animal Behaviour Science 262, 105899.

The welfare of animals used in scientific experiments should be one of the most important things to take care of. Many kinds of research show that the enriching elements can help animals to fulfil their...

Vas, J., BenSassi, N., Vasdal, G. et al. 2023. Better welfare for broiler chickens given more types of environmental enrichments and more space to enjoy them. Applied Animal Behaviour Science 261, 105901.

Providing an increased variety of environmental enrichment options, with sufficient space to use them, could increase the behavioural expression of positive affective states in production animals. The goal of this study was to investigate associations...

Beekmans, M. H. C., Vinke, C. M., Maijer, A. et al. 2023. Increasing foraging times with appetitive and consummatory foraging enrichment in grey parrots (Psittacus erithacus). Applied Animal Behaviour Science 265, 105986.

Foraging enrichment is considered one of the most effective ways to enhance expression of species-typical behaviours and prevent the development of abnormal (repetitive) behaviours in captive animals. However, foraging enrichments for parrots have thus far...

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...

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...

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...

Chan, K., Arellano, C., Horowitz, A. 2023. Here puppy, chew on this: Short-term provision of toys does not improve welfare in companion dogs. Animals 13(21), 3340.

Retail dog toys are often provided to companion animals to provide cognitive and physical stimu- lation and improve the animals’ quality of life. These toys, sometimes known as “enrichment toys”, have been shown to play...

Grandin, T. 2023. A practical approach to providing environmental enrichment to pigs and broiler chickens housed in intensive systems. Animals 13(14), 2372.

In Europe, regulations contain guidance to maintain high standards of animal welfare. In many parts of the world, large buyers for supermarkets or restaurants are the main enforcers of basic animal welfare standards. They can...

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...

Gunter, L. M., Blade, E. M., Gilchrist, R. J. et al. 2023. The influence of brief outing and temporary fostering programs on shelter dog welfare. Animals 13(22), 3528.

Human interaction is one of the most consistently effective interventions that can improve the welfare of shelter-living dogs. Time out of the kennel with a person has been shown to reduce physiological measures of stress...

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...

Majelantle, T. L., Ganswindt, A., Ganswindt, S. B. et al. 2023. Non-invasive quantification of faecal and urine reproductive hormone metabolites in the naked mole-rat (Heterocephalus glaber). Animals 13(19), 3039.

The naked mole-rat (Heterocephalus glaber) occurs in colonies with a distinct dominance hierarchy, including one dominant, breeding female (the queen), 1–3 breeding males, and non-reproductive subordinates of both sexes that are reproductively suppressed while in...

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...

Olczak, K., Penar, W., Nowicki, J. et al. 2023. The role of sound in livestock farming—Selected aspects. Animals 13(14), 2307.

To ensure the optimal living conditions of farm animals, it is essential to understand how their senses work and the way in which they perceive their environment. Most animals have a different hearing range compared...