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. 
Jacobs, L., Melick, S., Freeman, N. et al. 2021. Broiler chicken behavior and activity are affected by novel flooring treatments. Animals 11(10), 2841.

The objective was to determine broiler chicken behavioral differences in response to novel flooring treatments. Broilers (n = 182) were housed in 14 pens (a random subset from a larger-scale study including 42 pens), with...

Schwarzer, A., Plattner, C., Bergmann, S. et al. 2021. Feather pecking in non-beak-trimmed and beak-trimmed laying hens on commercial farms with aviaries. Animals 11(11), 3085.

Severe feather pecking (SFP) is a major animal welfare problem in layers. It results in pain and injuries in the affected animal. It was the aim of this study to gain insight into the actual...

Diana, A., Salas, M., Pereboom, Z. et al. 2021. A systematic review of the use of technology to monitor welfare in zoo animals: Is there space for improvement? Animals 11(11), 3048.

A top priority of modern zoos is to ensure good animal welfare (AW), thus, efforts towards improving AW monitoring are increasing. Welfare assessments are performed through more traditional approaches by employing direct observations and time-consuming...

Hu, J., Xiong, Y., Gates, R. S. et al. 2021. Perches as cooling devices for reducing heat stress in caged laying hens: A review. Animals 11(11), 3026.

Heat stress is one of the most detrimental environmental challenges affecting the biological process and the related production performance of farm animals, especially in poultry. Commercial laying hens have been bred (selected) for high egg...

de Jong, I. C., Blaauw, X. E., van der Eijk, J. E. J. et al. 2021. Providing environmental enrichments affects activity and performance, but not leg health in fast- and slower-growing broiler chickens. Applied Animal Behaviour Science 241, 105375.

Effects of environmental enrichment on activity, behaviour, walking ability, contact dermatitis and performance were investigated in fast- and slower-growing broiler chickens. A total of 840 day-old male broilers, 420 of a fast-growing strain (Ross 308)...

Forslind, S., Blokhuis, H. J., Riber, A. B. 2021. Disturbance of resting behaviour of broilers under different environmental conditions. Applied Animal Behaviour Science 242, 105425.

Resting behaviours make up a large part of the daily time budget of broilers. However, in intensive broiler production systems disruptions of resting behaviours occur, where resting individuals get disturbed by active individuals. Such interruptions...

Sirovnik, J., Euteneuer, P., König von Borstel, U. 2021. An attempt to use sound-imprinting to attract broilers onto elevated platforms for night-time roosting. Applied Animal Behaviour Science 243, 105448.

Welfare of fast growing broilers is often compromised due to leg health issues. A more complex environment such as the provision of elevated platforms facilitates activity and improves leg health in fast growing broilers. Thus...

Balasubramaniam, K. N., Beisner, B. A., McCowan, B. et al. 2021. Female social structure influences, and is influenced by, male introduction and integration success among captive rhesus macaques (Macaca mulatta). Behaviour 158(11), 1007–1042.

Animal social structure is influenced by multiple socioecological factors. Of these, the links between changes to group demography through the arrival of new individuals and residents' social structure remain unclear. Across seven groups of captive...

MacLellan, A., Fureix, C., Polanco, A. et al. 2021. Can animals develop depression? An overview and assessment of “depression-like” states. Behaviour 158(14/15), 1303–1353.

Describing certain animal behaviours as 'depression-like' or 'depressive' has become common across several fields of research. These typically involve unusually low activity or unresponsiveness and/or reduced interest in pleasure (anhedonia). While the term 'depression-like' carefully...

Campbell, D. L. M., Lee, C. 2021. A perspective on strategic enrichment for brain development: Is this the key to animal happiness? Frontiers in Veterinary Science 8, 720422.

Livestock animals are sentient beings with cognitive and emotional capacities and their brain development, similar to humans and other animal species, is affected by their surrounding environmental conditions. Current intensive production systems, through the restrictions...

Falendysz, E. A., Calhoun, D. M., Smith, C. A. et al. 2020. Outside the box: Working with wildlife in biocontainment. ILAR Journal 61(1), 72-85.

Research with captive wildlife in Animal Biosafety Level 2 (ABSL2) and 3 (ABSL3) facilities is becoming increasingly necessary as emerging and re-emerging diseases involving wildlife have increasing impacts on human, animal, and environmental health. Utilizing...

Bowling, P. A., Bencivenga, M. A., Leyva, M. E. et al. 2021. Effects of a heated anesthesia breathing circuit on body temperature in anesthetized rhesus macaques (Macaca mulatta). JAALAS 60(6), 675-680.

This study evaluated the effects of using a heated anesthesia breathing circuit in addition to forced-air warming on body temperature in anesthetized rhesus macaques as compared with forced-air warming alone. Hypothermia is a common perianesthetic...

Tölgyesi, B., Bakker, J., Nagy, K. et al. 2021. Refined acquisition of high-resolution chest CTs in macaques by free breathing. Laboratory Animals 55(6), 551-559.

The use of medical imaging as a non-invasive or minimally invasive method to assess disease or treatment response continues to grow. A similar trend is observed in pre-clinical research, in general, and more specifically in...

Lambert, K. 2021. DIY: Acacia gum hanging saucer. Laboratory Animal Science Professional 9(5) (September/October), 50.

This article describes the ingredients, supplies, and directions to make this DIY hanging item, which is great for NHP and swine.

Lambert, K. 2021. DIY: Busy boxes. Laboratory Animal Science Professional 9(6) (November/December), 32.

This article describes the ingredients and directions to make this simple DIY destructible enrichment for NHP and swine.

Lourenço da Silva, M. I., Almeida Paz, I., Chaves, G. et al. 2021. Behaviour and animal welfare indicators of broiler chickens housed in an enriched environment. PLOS ONE 16(9), e0256963.

The present study aimed to assess the influence of adding straw bales, step platforms, and laser projectors as environmental enrichment resources on the behaviour and welfare indicators of broiler chickens (Gallus gallus domesticus). A sample...

Penfold, L. M., Norton, T., Asa, C. S. 2021. Effects of GnRH agonists on testosterone and testosterone-stimulated parameters for contraception and aggression reduction in male lion-tailed Macaques (Macaca silenus). Zoo Biology 40(6), 541-550.

Managing social groups in zoos requires controlling reproduction in individuals that do not have a current breeding recommendation, while simultaneously maintaining social harmony and animal well-being. Contraceptives, such as gonadotropin releasing-hormone (GnRH) agonists, that suppress...

Anderson, M. G., Campbell, A. M., Crump, A. et al. 2021. Environmental complexity positively impacts affective states of broiler chickens. Scientific Reports 11(1), 16966.

Affective state can bias an animal’s judgement. Animals in positive affective states can interpret ambiguous cues more positively (“optimistically”) than animals in negative affective states. Thus, judgement bias tests can determine an animal’s affective state...

Wood, B., Rufener, C., Makagon, M. M. et al. 2021. The utility of scatter feeding as enrichment: Do broiler chickens engage with scatter–fed items? Animals 11(12), 3478.

In recent years, welfare certification companies have encouraged the use of scatter feeding as enrichment material, though there is little scientific evidence to support a scatter feeding program. This study aimed to understand the impact...

Sans, E. C. de O., Tuyttens, F. A. M., Taconeli, C. A. et al. 2021. From the point of view of the chickens: What difference does a window make? Animals 11(12), 3397.

We aimed to investigate what broiler chickens prefer when given free choice between a barn side with artificial lighting only as opposed to the other barn side with natural light through glass windows and artificial...

Ciborowska, P., Michalczuk, M., Bień, D. 2021. The effect of music on livestock: Cattle, poultry and pigs. Animals 11(12), 3572.

The welfare of animals, especially those kept in intensive production systems, is a priority for modern agriculture. This stems from the desire to keep animals healthy, to obtain a good-quality final product, and to meet...

Güz, B. C., de Jong, I. C., Da Silva, C. S. et al. 2021 Effects of pen enrichment on leg health of fast and slower-growing broiler chickens. PLOS ONE 16(12), e0254462.

Pen enrichment for broiler chickens is one of the potential strategies to stimulate locomotion and consequently contribute to better leg health and welfare. This study was designed to evaluate effects of using a plethora of...

Watson, P. 2021. Management of naked mole rats (Heterocephalus glaber) at Chester Zoo. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 48(3), 24-26.

This species first arrived at Chester Zoo in June 2014 when a colony of 27 animals was imported from Dresden Zoo, Germany. As with any new species our journey with naked mole rats has not...

Guerrero-Martin, S. M., Rubin, L. H., McGee, K. M. et al. 2021. Psychosocial stress alters the immune response and results in higher viral load during acute simian immunodeficiency virus infection in a pigtailed macaque model of human immunodeficiency virus. The Journal of Infectious Diseases 224(12), 2113–2121.

Although social distancing is a key public health response during viral pandemics, psychosocial stressors, such as social isolation, have been implicated in adverse health outcomes in general [1] and in the context of infectious disease...

Costantino, A., Fabrizio, E., Calvet, S. 2021. The role of climate control in monogastric animal farming: The effects on animal welfare, air emissions, productivity, health, and energy use. Applied Sciences 11(20), 9549.

In the last decades, an engineering process has deeply transformed livestock houses by introducing fine-tuned climate control systems to guarantee adequate indoor climate conditions needed to express the maximum genetic potential of animals and to...