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. 
Dickmann, J., Gonzalez-Uarquin, F., Reichel, S. et al. 2022. Clicker training mice for improved compliance in the catwalk test. Animals 12(24), 3545.

The CatWalk test relies on the run of mice across the platform to measure a constant speed with low variation. Mice usually require a stimulus to walk to the end of the catwalk. However, such...

Mieske, P., Hobbiesiefken, U., Fischer-Tenhagen, C. et al. 2022. Bored at home?—A systematic review on the effect of environmental enrichment on the welfare of laboratory rats and mice. Frontiers in Veterinary Science 9, 899219.

Boredom is an emotional state that occurs when an individual has nothing to do, is not interested in the surrounding, and feels dreary and in a monotony. While this condition is usually defined for humans...

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...

Reifenrath, J., Heider, M., Kempfert, M. et al. 2022. Buprenorphine in rats: Potent analgesic or trigger for fatal side effects? Acta Veterinaria Scandinavica 64(1), 37.

With ongoing animal welfare efforts, multimodal analgesia is often recommended to implement in study protocols. Buprenorphine with very potent analgesic effect is a standard opioid for the use in this context in rats. In this...

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...

Wahltinez, S. J., Stacy, N. I., Hadfield, C. A. et al. 2022. Perspective: Opportunities for advancing aquatic invertebrate welfare. Frontiers in Veterinary Science 9, 973376.

Welfare considerations and regulations for invertebrates have lagged behind those for vertebrates, despite invertebrates comprising more than 95% of earth’s species. Humans interact with and use aquatic invertebrates for exhibition in zoos and aquaria, as...

Xu, D., Shu, G., Liu, Y. et al. 2022. Farm animal enrichments improve the welfare of layer chicks and pullets: A comprehensive review. Animals 12(19), 2610.

Currently, cage housing is regarded as a global mainstream production system for laying hens. However, limited living space and confinement of birds in cages cause welfare and health problems, such as feather pecking, osteoporosis, obesity...

Cait, J., Cait, A., Scott, R. W. et al. 2022. Conventional laboratory housing increases morbidity and mortality in research rodents: Results of a meta-analysis. BMC Biology 20(1), 15.

Over 120 million mice and rats are used annually in research, conventionally housed in shoebox-sized cages that restrict natural behaviours (e.g. nesting and burrowing). This can reduce physical fitness, impair thermoregulation and reduce welfare (e.g...

Lima, A. F., Lima, S. G. C., Nogueira-Filho, S. L. G. et al. 2022. Vocal expression of emotions in farmed spotted paca (Cuniculus paca). Applied Animal Behaviour Science 256, 105753.

Vocal emissions in non-human mammals can be used as non-invasive indicators of animal emotion and welfare. Therefore, we aimed to validate the use of acoustic parameters as indicators of affective states and welfare in farmed...

Brough, D. W., Murkin, J. T., Amos, H. E. et al. 2022. Comparing variability in measurement of subcutaneous tumors in mice using 3D thermal imaging and calipers. Comparative Medicine 72(6), 364–375.

Repeatable tumor measurements are key to accurately assessing tumor growth and treatment efficacy. A preliminary study that we conducted showed that a novel 3D and thermal imaging system (3D-TI) for measuring subcutaneous tumors in rodents...

Giral, M., Armengol, C., Gavaldà, A. 2022. Physiologic effects of housing rats in metabolic cages. Comparative Medicine 72(5), 298–305.

Currently, metabolic cages (MC) are the only way to achieve serial sampling of urine and feces in rodents. However, the use of this caging creates a dramatic change from an animal’s usual microenvironment. Here we...

Zhang, H., Zhu, B., Yu, L. et al. 2022. Shelter color selection of juvenile swimming crabs (Portunus trituberculatus). Fishes 7(5), 296.

Color preference testing for animals is a prerequisite for optimizing facilities and ensuring animal welfare in aquaculture. Swimming crabs (Portunus trituberculatus) are aggressive, and shelters are often installed in ponds to reduce the high mortality...

Briffa, M. 2022. When should we ascribe sentience to animals? A commentary on “Hermit crabs, shells and sentience” (Elwood 2022). Animal Cognition 25(6), 1375–1380.

In a new review article, experiments on hermit crab behaviour are discussed in the context of possible animal sentience. Sentience can be defined as the ability to experience feelings such as pleasure or pain but...

Elwood, R. W. 2022. Caution is required when considering sentience in animals: A response to the commentary by Briffa (2022) on “Hermit crabs, shells, and sentience” (Elwood 2022). Animal Cognition 25(6), 1371–1374.

My recent review examined the complex and intimate relationship between hermit crabs and the empty gastropod shells upon which they depend for survival. Because shells come with costs as well as benefits, the crabs are...

Elwood, R. W. 2022. Hermit crabs, shells, and sentience. Animal Cognition 25(5), 1241–1257.

Hermit crabs have an intimate relationship with gastropod shells and show numerous activities by which they locate, select, and change shells in different contexts. They gather information about new shells and update information about their...

Molina, S. J., Lietti, Á. E., Carreira Caro, C. S. et al. 2022. Effects of early noise exposure on hippocampal-dependent behaviors during adolescence in male rats: Influence of different housing conditions. Animal Cognition 25(1), 103–120.

Central nervous system (CNS) development is a very complex process that can be altered by environmental stimuli such as noise, which can generate long-term auditory and/or extra-auditory impairments. We have previously reported that early noise...

Riedel, A., Rieke, L., Kemper, N. et al. 2022. A place to be? Use of winter gardens with and without automatic enrichment devices by laying hens. Applied Sciences 12(7), 3650.

Since the abolition of beak trimming in laying hens in Germany, the importance of adequate enrichment material to help reduce feather pecking and cannibalism has grown. Here we tested an automatic enrichment device dosing grain...

Takahashi, K. 2022. Changes in the anxiety-like and fearful behavior of shrimp following daily threatening experiences. Animal Cognition 25(2), 319–327.

Behavioral variation in animals is often influenced by experience. Previous studies have found that daily threatening experiences can enhance fear- and anxiety-like behaviors in some vertebrates. However, it is unclear whether the change in fear/anxiety...

Zeng, Y., Jin, H., Wang, J. et al. 2022. An optimized method for intratracheal instillation in mice. Journal of Pharmacological and Toxicological Methods 118, 107230.

Non-invasive intratracheal instillation is an important method for direct exposure of the respiratory tract which is commonly used in toxicology, environmental science, and other research fields. However, there is no standard operating process for non-invasive...

Whitbread, S. 2022. Some observations on the use of transparent barriers. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 49(3), 9-13.

What follows are some case studies in which solid but transparent barriers have been used successfully to provide a sense of security to three different mammal taxa (three-banded armadillo; Kirk’s dikdik; black rat) to reduce...

Costa, R., Carvalho, M. S. M., Brandão, J. D. P. et al. 2021. Modulatory action of environmental enrichment on hormonal and behavioral responses induced by chronic stress in rats: Hypothalamic renin-angiotensin system components. Behavioural Brain Research 397, 112928.

Environmental enrichment (EE) has been studied as a protocol that can improve brain plasticity and may protect against negative insults such as chronic stress. The aim of this study was to evaluate the effects of...

Oatess, T. L., Harrison, F. E., Himmel, L. E. et al. 2021. Effects of acrylic tunnel enrichment on anxiety-like behavior, neurogenesis, and physiology of C57BL/6J mice. JAALAS 60(1), 44-53.

Environmental enrichment for mice lags behind the standard enrichment offered to other laboratory rodents due to concerns about environmental variability and, in specific contexts, aggression. Our objective in this study was to evaluate concerns that...

Schalbetter, S. M., Mueller, F. S., Scarborough, J. et al. 2021. Oral application of clozapine-N-oxide using the micropipette-guided drug administration (MDA) method in mouse DREADD systems. Lab Animal 50, 69-75.

The designer receptor exclusively activated by designer drugs (DREADD) system is one of the most widely used chemogenetic techniques to modulate the activity of cell populations in the brains of behaving animals. DREADDs are activated...

Atkinson, J., Boden, T., Mocho J.-P. et al. 2021. Refining the unilateral ureteral obstruction mouse model: No sham, no shame. Laboratory Animals 55(1), 21-29.

Fibrosis, as a common final pathway in many renal diseases, contributes significantly to the decline of organ function and to progression to end-stage renal disease. To establish therapeutic interventions that target fibrosis, animal models are...

Teixeira-Santos, L., Albino-Teixeira, A., Pinho, D. 2021. An alternative method for oral drug administration by voluntary intake in male and female mice. Laboratory Animals 55(1), 76-80.

Drug administration to experimental rodents is often invasive and stressful, thus reducing animal welfare and potentially confounding experimental results. Methods of oral drug delivery in which rodents cooperate voluntarily minimize stress, pain and morbidity. We herein...