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. 
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...

Malik, A., Zavadil, J. A., Geusz, M. E. 2023. Using bioluminescence to image gene expression and spontaneous behavior in freely moving mice. PLOS ONE 18(1), e0279875.

Bioluminescence imaging (BLI) of gene expression in live animals is a powerful method for monitoring development, tumor growth, infections, healing, and other progressive, long-term biological processes. BLI remains an effective approach for reducing the number...

Mauthe von Degerfeld, M., Serpieri, M., Bonaffini, G. et al. 2023. Intranasal atomization of ketamine, medetomidine and butorphanol in pet rabbits using a mucosal atomization device. Animals 13(13), 2076.

A non-invasive method of drug delivery, intranasal atomization, has shown positive results in human medicine and in some animal species. The objective of this study was to evaluate the effects of intranasal atomization, compared to...

Palumbo, G., Kunze, L. H., Oos, R. et al. 2023. Longitudinal studies on Alzheimer disease mouse models with multiple tracer PET/CT: Application of reduction and refinement principles in daily practice to safeguard animal welfare during progressive aging. Animals 13(11), 1812.

Longitudinal studies on mouse models related to Alzheimer disease (AD) pathology play an important role in the investigation of therapeutic targets to help pharmaceutical research in the development of new drugs and in the attempt...

Swan, J., Boyer, S., Westlund, K. et al. 2023. Decreased levels of discomfort in repeatedly handled mice during experimental procedures, assessed by facial expressions. Frontiers in Behavioral Neuroscience 17, 1109886.

Mice are the most commonly used laboratory animal, yet there are limited studies which investigate the effects of repeated handling on their welfare and scientific outcomes. Furthermore, simple methods to evaluate distress in mice are...

Xu, J. J., Lucero, M. Y., Herndon, N. L. et al. 2023. Comparison of a minimally invasive transthoracic approach and a surgical method for intrapleural injection of tumor cells in mice. Comparative Medicine 73(2), 120–126.

Intrapleural injections can be used in mice to deliver therapeutic and diagnostic agents and to model human disease processes (for example, pleural fluid accumulation, malignant pleural disease, and lung cancers). In the context of establishing...

Pérez-Martín, E., Coto-Vilcapoma, A., Castilla-Silgado, J. et al. 2023. Refining stereotaxic neurosurgery techniques and welfare assessment for long-term intracerebroventricular device implantation in rodents. Animals 13(16), 2627.

Stereotaxic surgeries enable precise access to specific brain regions, being of particular interest for chronic intracerebroventricular drug delivery. However, the challenge of long-term studies at this level is to allow the implantation of drug storage...

Wang, C., Yang, C., Zeng, Y. et al. 2023. GnRH-immunocastration: An alternative method for male animal surgical castration. Frontiers in Veterinary Science 10.
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...

Baker, P. E., Nicol, C. J., Weeks, C. A. 2022. The effect of hard pecking enrichment during rear on feather cover, feather pecking behaviour and beak length in beak-trimmed and intact-beak laying hen pullets. Animals 12(6), 674.

Injurious pecking, commonly controlled by beak trimming (BT), is a widespread issue in laying hens associated with thwarted foraging. This controlled study compared the effect in intact and beak-trimmed pullets of providing pecking pans to...

Knaebe, B., Weiss, C. C., Zimmermann, J. et al. 2022. The promise of behavioral tracking systems for advancing primate animal welfare. Animals 12(13), 1648.

Recent years have witnessed major advances in the ability of computerized systems to track the positions of animals as they move through large and unconstrained environments. These systems have so far been a great boon...

Fares, R., Flénet, T., Vial, J. et al. 2022. Non invasive jacketed telemetry in socially-housed rats for a combined assessment of respiratory system, electrocardiogram and activity using the DECRO system. Journal of Pharmacological and Toxicological Methods 117, 107195.

Respiratory and cardiovascular systems are among the vital organ systems that should be studied in safety pharmacology core battery test. Non-invasive jacketed external telemetry technology that enables concomitant monitoring of both systems has been available...

Scariot, P. P., Gobatto, C. A., Polisel, E. E. et al. 2022. Early-life mice housed in standard stocking density reduce the spontaneous physical activity and increase visceral fat deposition before reaching adulthood. Laboratory Animals 56(4), 344-355.

Laboratory rodents spend the entire day housed in standard cages that provide a restricted area for movements and might, therefore, limit physical activity. However, it has not been tested in immature rodents of ages ranging...

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...

Xie, W., Lorenz, M., Poosch, F. et al. 2022. 3D-printed lightweight dorsal skin fold chambers from PEEK reduce chamber-related animal distress. Scientific Reports 12(1), 11599.

The dorsal skinfold chamber is one of the most important in vivo models for repetitive longitudinal assessment of microcirculation and inflammation. This study aimed to refine this model by introducing a new lightweight chamber made...

Chen, T., Zhou, Z.-Y., Liu, J.-Y. et al. 2022. Impact of partial bile duct ligation with or without repeated magnetic resonance imaging examinations in mice. Scientific Reports 12(1), 21014.

Partial bile duct ligation (pBDL) is considered a well-tolerated cholestatic model. Magnetic resonance imaging (MRI) is one of the most widely used tools in noninvasive imaging. However, no systematic studies have reported the possible effects...

Nuber, M., Gonzalez-Uarquin, F., Neufurth, M. et al. 2022. Development of a 3D simulator for training the mouse in utero electroporation. PLOS ONE 17(12), e0279004.

In utero electroporation (IUE) requires high-level training in microinjection through the mouse uterine wall into the lateral ventricle of the mouse brain. Training for IUE is currently being performed in live mice as no artificial...

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...

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...

Krueger, L. D., Chang, S. E., Motoc, M. et al. 2021. Effects of pair housing on patency of jugular catheters in rats (Rattus norvegicus). JAALAS 60(3), 357-364.

Chronic vascular access devices are widely used in a variety of species for repeated blood sampling or substance administration. Jugular catheters are commonly used for studying addiction-related behaviors in rats. Rats with catheters have historically...

Koch, A. L., Rusnak, M., Peachee, K. et al. 2021. Comparison of the effects of osmotic pump implantation with subcutaneous injection for administration of drugs after total body irradiation in mice. Laboratory Animals 55(2), 142-149.

The increasing potential for radiation exposure from nuclear accidents or terrorist activities has intensified the need to develop pharmacologic countermeasures against injury from total body irradiation (TBI). Many initial experiments to develop and test these...

Windsor, Z. 2021. Refinements in head plate mouse nesting: Using composite nests to enhance welfare. Animal Technology and Welfare 20(2), 135-141.

When given the opportunity, mice will choose to build nests using multiple different materials. Studies indicate that providing mice with choices which mimic the natural environment allows laboratory mice to build the best quality nests...

Onozawa, E., Azakami, D., Seki, S. et al. 2021. Effect of an insulation device in preventing hypothermia during magnetic resonance imaging examinations for dogs and cats under general anesthesia. Animals 11(8), 2378.

Dogs and cats under general anesthesia may develop hypothermia. When performing a magnetic resonance imaging (MRI) examination, it is not possible to place a magnetic material in the MRI room, and MRI equipment requires a...