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. 
Dawkins, M. S. 2024. Active walking in broiler chickens: A flagship for good welfare, a goal for smart farming and a practical starting point for automated welfare recognition. Frontiers in Veterinary Science 10.

Automated assessment of broiler chicken welfare poses particular problems due to the large numbers of birds involved and the variety of different welfare measures that have been proposed. Active (sustained, defect-free) walking is both a...

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...

Cohen, S., Ho, C. 2023. Review of rat (Rattus norvegicus), Mouse (mus musculus), Guinea pig (Cavia procellus), and rabbit (Oryctolagus cuniculus) indicators for welfare assessment. Animals 13(13), 2167.

The monitoring and assessment of animals is important for their health and welfare. The appropriate selection of multiple, validated, and feasible welfare assessment indicators is required to effectively identify compromises or improvements to animal welfare...

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...

Paneru, B., Pent, G. J., Nastasi, S. et al. 2023. Effect of silvopasture system on fearfulness and leg health in fast-growing broiler chickens. PLOS ONE 18(3), e0282923.

A silvopasture system intentionally integrates trees, forages, and livestock, allowing dual land use. These systems can provide high-quality habitat for broiler chickens; however, such systems have not been widely adopted by the broiler industry in...

Sokołowicz, Z., Dykiel, M., Topczewska, J. et al. 2023. A comparison of the plumage condition of three egg-laying poultry genotypes housed in non-cage systems. Animals 13(2), 185.

The study covered a total of 810 hens in 3 groups (housing systems) of 270 hens each. The plumage condition of laying hens raised in various types of alternative housing systems, i.e., in deep litter...

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...

Veness, A., Coyle, C., Murphy, S. et al. 2023. Minimising aggression in CD-1 and CD-1 background male mice with different enrichment types. Animal Technology and Welfare 22(1), 74–76.

Cage-mate aggression is a well-known problem that is more prevalent in certain strains of mice and is one of the most common reasons for single housing, increased stress levels, premature death and euthanasia. Numerous methods...

Holt, R. V., Vas, J., Vasdal, G. et al. 2023. A buffet of litters – Broiler chickens behave differently according to litter type and freshness. Applied Animal Behaviour Science 260, 105856.

Poultry are usually provided with a single litter type that may not satisfy all litter-directed behavioural functions and may lose functional value over time due to soiling and degradation. We investigated this hypothesis in two...

Moëne, O. L., Larsson, M. 2023. A new tool for quantifying mouse facial expressions. ENeuro 10(2) ENEURO.0349-22.2022.

Facial expressions are an increasingly used tool to assess emotional experience and affective state during experimental procedures in animal models. Previous studies have successfully related specific facial features with different positive and negative valence situations...

Anderson, M. G., Johnson, A. M., Jacobs, L. et al. 2023. Influence of perch-provision timing on anxiety and fearfulness in laying hens. Animals 13(19), 3003.

Perches can enhance laying hen welfare, but their effectiveness might be age-dependent. We investigated early and late perch access effects on anxiety and fear in pullets through attention bias (AB) and tonic immobility (TI) tests...

Cordeira, J. 2023. Daily replacement of very high-fat diet stabilizes food intake and improves mouse welfare by ensuring food quality. PLOS ONE 18(9), e0291347.

Researchers are obligated to ensure food quality and provide laboratory animals with a palatable diet. Factors influencing the quality and palatability of very high-fat diet (VHFD), a widely used rodent diet, however, are understudied. We...

Dietrich, T., Aigner, A., Hildebrandt, A. et al. 2023. Nesting behavior is associated with body weight and grip strength loss in mice suffering from experimental arthritis. Scientific Reports 13(1), 23087.

Objective animal health evaluation is essential to determine welfare and discomfort in preclinical in vivo research. Body condition scores, body weight, and grimace scales are commonly used to evaluate well-being in murine rheumatoid arthritis (RA)...

Goma, A. A., Uddin, J., Kieson, E. 2023. Lateralised behavioural responses in livestock to environmental stressors: Implications for using infrared thermography to assess welfare conditions. Animals 13(23), 3663.

Lateralised behavioural responses to environmental stressors have become more frequently used as indicators of social welfare in animals. These lateralised behavioural responses are under the control of asymmetrical brain functions as part of the primary...

Kodaira, V., Siriani, A. L. R., Medeiros, H. P. et al. 2023. Assessment of preference behavior of layer hens under different light colors and temperature environments in long-time footage using a computer vision system. Animals 13(15), 2426.

As for all birds, the behavior of chickens is largely determined by environmental conditions. In many production systems, light intensity is low and red feather strains have low contrast with the background, making it impossible...

rueger, J. C., Boecker, M., Gauggel, S. et al. 2023. Using photographs for rating severity degrees of clinical appearance in research mice enables valid discrimination of extreme but not mild and moderate conditions: A pilot study. PLOS ONE 18(11), e0287965.

To ensure good animal welfare in laboratory research and in stockbreeding severity ratings of the animals´ wellbeing are essential. The current study investigated how valid raters can evaluate different severity degrees of clinical appearance and...

Montalcini, C. M., Petelle, M. B., Toscano, M. J. 2023. Commercial hatchery practices have long-lasting effects on laying hens’ spatial behaviour and health. PLOS ONE 18(12), e0295560.

The commercial hatchery process is globally standardized and exposes billions of day-old layer chicks to stress every year. By alleviating this early stress, on-farm hatching is thought to improve animal welfare, yet little is known...

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...

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...

Reiber, M., Schumann, L. von, Buchecker, V. et al. 2023. Evidence-based comparative severity assessment in young and adult mice. PLOS ONE 18(10), e0285429.

In animal-based research, welfare assessments are essential for ethical and legal reasons. However, accurate assessment of suffering in laboratory animals is often complicated by the multidimensional character of distress and pain and the associated affective...

Sadeghi, M., Banakar, A., Minaei, S. et al. 2023. Early detection of avian diseases based on thermography and artificial intelligence. Animals 13(14), 2348.

Non-invasive measures have a critical role in precision livestock and poultry farming as they can reduce animal stress and provide continuous monitoring. Animal activity can reflect physical and mental states as well as health conditions...

Tanaka, Y., Nakata, T., Hibino, H. et al. 2023. Classification of multiple emotional states from facial expressions in head-fixed mice using a deep learning-based image analysis. PLOS ONE 18(7), e0288930.

Facial expressions are widely recognized as universal indicators of underlying internal states in most species of animals, thereby presenting as a non-invasive measure for assessing physical and mental conditions. Despite the advancement of artificial intelligence-assisted...

Wittek, L., Touma, C., Nitezki, T. et al. 2023. Reduction in cold stress in an innovative metabolic cage housing system increases animal welfare in laboratory mice. Animals 13(18), 2866.

Housing in metabolic cages can induce a pronounced stress response. Metabolic cage systems imply housing mice on metal wire mesh for the collection of urine and feces in addition to monitoring food and water intake...

Paul, E. S., Browne, W., Mendl, M. T. et al. 2022. Assessing animal welfare: A triangulation of preference, judgement bias and other candidate welfare indicators. Animal Behaviour 186, 151-177.

To assess the welfare of captive animals, validated measures, so-called ‘welfare indicators’, are required. We used a triangulation approach to investigate the extent to which different measures converged to provide corroborating evidence of welfare. Laying...

Rowe, E., Mullan, S. 2022. Advancing a “good life” for farm animals: Development of resource tier frameworks for on-farm assessment of positive welfare for beef cattle, broiler chicken and pigs. Animals 12(5), 565.

There is increasing recognition that farm animal welfare standards should ensure positive welfare, as well as prevent negative welfare. Resources that are valued by an animal and that provide opportunities to engage in motivated behaviours...