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...

Lambert, H., Cornish, A., Waley, D. 2024. The value of regulating stocking densities in aquaculture must not be dismissed: A reply to Saraiva et al. 2022. Frontiers in Veterinary Science 10.

We would like to rebut the argument made by Saraiva et al. (1) in their paper “Finding the “golden stocking density”: a balance between fish welfare and farmers' perspectives,” that stocking densities should not be...

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...

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)...

Moise, R. I., Eccles, G. R., Mettke-Hofmann, C. 2023. Enclosure background preferences differ between sexes and color morphs in the Gouldian finch. Animals 13(8), 1353.

Most wild animals camouflage well into their environment, providing protection from predators, whereas captive animals often contrast with their background. This can cause stress for the animal, which may perceive it as being exposed. Theory...

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...

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...

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...

Goodenough, A. E., Sewell, A., McDonald, K. 2023. Behavioural patterns in zoo-housed Humboldt penguins (Spheniscus humboldti) revealed using long-term keeper-collected data: Validation of approaches and improved husbandry. Applied Animal Behaviour Science 258, 105811.

Given the increasing obligation to elevate animal welfare beyond minimum expectations, zoos need robust mechanisms to monitor physical activity and species-appropriate behaviours. This is not without challenge as animal behaviour can vary seasonally or be...

Campbell-Ward, M. 2023. Quality-of-life assessments in zoo animals: Not just for the aged and charismatic. Animals 13(21), 3394

Zoos should aim to provide all of their animals with a good quality of life (QoL) throughout all life stages. In parallel with the evolution of QoL assessment questionnaires and tools in human and domestic...

Fuller, G., Jones, M., Gartland, K. N. et al. 2023. The benefits of increased space and habitat complexity for the welfare of zoo-housed king penguins (Aptenodytes patagonicus). Animals 13(14), 2312.

Zoos and aquariums accredited by the Association of Zoos and Aquariums embrace animal welfare as a foundational principle of habitat design. Modern habitats are designed to provide animals with choices and agency over their environment...

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...

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...

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...

Wiese, T. R., Rey Planellas, S., Betancor, M. et al. 2023. Qualitative Behavioural Assessment as a welfare indicator for farmed Atlantic salmon (Salmo salar) in response to a stressful challenge. Frontiers in Veterinary Science 10.

Animal welfare assessments have struggled to investigate the emotional states of animals while focusing solely on available empirical evidence. Qualitative Behavioural Assessment (QBA) may provide insights into an animal’s subjective experiences without compromising scientific rigor...

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...

Rana, M. S., Lee, C., Lea, J. M. et al. 2022. Commercial free-range laying hens’ preferences for shelters with different sunlight filtering percentages. Animals 12(3), 344.

Extreme sunlight might be aversive to free-range laying hens, discouraging them from going outside. Range enrichment with artificial shelters may protect hens from sunlight and increase range use. The preferences of 34–40-week-old Hy-Line Brown 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...

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...

Mels, C., Niebuhr, K., Futschik, A. et al. 2022. Predictors for plumage damage and bloody lesions indicative of feather pecking in pullets reared in aviaries. Applied Animal Behaviour Science 250, 105607.

Feather pecking remains a serious problem in poultry farming. This study aimed to identify risk factors for plumage damage as a proxy for feather pecking, and the predictive value of practical animal-based parameters. Data were...

Kalnins, L., Krüger, O., Krause, E. T. 2022. Plumage and fat condition scores as well-being assessment indicators in a small passerine bird, the zebra finch (Taeniopygia guttata). Frontiers in Veterinary Science 9, 791412.

The well-being of animals kept by humans in laboratories, farms, or as pets should always be of the highest importance, and a prerequisite for this is adequate housing. To assess the potential indicators for animal...

Campbell, A. M., Johnson, A. M., Persia, M. E. et al. 2022. Effects of housing system on anxiety, chronic stress, fear, and immune function in Bovan brown laying hens. Animals 12(14), 1803.

The scientific community needs objective measures to appropriately assess animal welfare. The study objective was to assess the impact of housing system on novel physiological and behavioral measurements of animal welfare for laying hens, including...

Ragland, N. H., Compo, N. R., Wiltshire, N. et al. 2022. Housing and husbandry alternatives for naked mole rat colonies used in research settings. JAALAS 61(5), 412-418.

Naked mole rats (Heterocephalus glaber) are a unique rodent species originating in Africa and are increasingly being used in research. Their needs and characteristics differ from those of other rodents used in research. Unique housing...

Abazaris, J., Hashway, S. 2022. Vole husbandry at Colorado University Boulder. Laboratory Animal Science Professional 10(4) (July/August), 12-15.

Since they arrived at CU Boulder, we have learned a lot about the voles from the laboratory, other institutions, and our trial-and-error. We hope this information can be helpful to any considering adding voles to...