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. 
Anderson, J. R., Ang, M. Y. L., Lock, L. C. et al. 2019. Nesting, sleeping, and nighttime behaviors in wild and captive great apes. Primates 60(4), 321–332.

The past few decades have seen a burgeoning of scientific studies on great apes’ use of nests for sleeping in the wild, as well as their nesting behavior and sleep in captivity. We review recent...

Wang, X., Zhang, Y., Lu, T. et al. 2019. The effect of cage ventilation rate on the health of mice housed in Individually Ventilated Cages. Scandinavian Journal of Laboratory Animal Science 45(3).

The number of air changes per hour (ACH), an important index for individually ventilated cages (IVC), strongly affects the cage microenvironment and the health of laboratory animals. The objective of this study was to determine...

Ross, M., Garland, A., Harlander-Matauschek, A. et al. 2019. Welfare-improving enrichments greatly reduce hens' startle responses, despite little change in judgment bias. Scientific Reports 9, 11881.

Responses to ambiguous and aversive stimuli (e.g. via tests of judgment bias and measures of startle amplitude) can indicate mammals’ affective states. We hypothesised that such findings generalize to birds, and that these two responses...

Lidster, K., Owen, K., Browne, W. J. et al. 2019. Cage aggression in group-housed laboratory male mice: An international data crowdsourcing project. Scientific Reports 9, 15211.

Aggression in group-housed laboratory mice is a serious animal welfare concern. Further understanding of the causes of mouse aggression could have a significant impact on a large number of laboratory animals. The NC3Rs led a...

Jung, L., Knierim, U. 2019. Differences between feather pecking and non-feather pecking laying hen flocks regarding their compliance with recommendations for the prevention of feather pecking – A matched concurrent case-control design. Applied Animal Behaviour Science 219, 104839.

Feather pecking (FP) is a multifactorial problem in all housing systems. Using a case-control design we wanted to determine a set of variables which may be decisive for a flock to become case or control...

Cox, R. J., Nol, P., Ellis, C. K. et al. 2019. Research with agricultural animals and wildlife. ILAR Journal 60(1), 66-73.

In fiscal year 2016, agricultural animals such as swine, sheep, goats, and cattle represented 10% of the 820 812 animals used in USDA-regulated research. In addition to traditional agricultural animals, research studies using captive wildlife...

Sanchez-Casanova, R., Sarmiento-Franco, L., Segura-Correa, J. et al. 2019. Effects of outdoor access and indoor stocking density on behaviour and stress in broilers in the subhumid tropics. Animals 9(12), 1016.

Studies investigating the welfare of commercial-line broiler chickens raised in houses with outdoor access in the tropics are scarce, and none have investigated whether responses vary according to indoor conditions. Hence, we assessed the effects...

Hubert, S., Al-Ajeeli, M., Bailey, C. et al. 2019. The role of housing environment and dietary protein source on the gut microbiota of chicken. Animals 9(12), 1085.

The gut microbiota of chicken has received much attention due to its importance for bird health, food safety, and performance. In the United States, the impending transition to cage-free housing environments has raised many questions...

Morgunowicz, A., Cavanagh, C., Nikitochkina, S. et al. 2019. Increased incidence of spontaneous seizures in laboratory mice in an IVC environment. Animal Technology and Welfare 18(3), 159-166.

Over the past decade, there has been an enormous shift away from the use of open top rodent cages to the use of individually ventilated cages (IVCs). This has brought with it many benefits, including...

Zidar, J., Weber, E. M., Ewaldsson, B. et al. 2019. Group and single housing of male mice: Collected experiences from research facilities in Sweden. Animals 9(12), 1010.

The mouse is the most commonly used mammal in scientific research, and housed in research facilities around the world. Mice are a social species, but when housing male mice together in a confined environment in...

Jirkof, P., Rudeck, J., Lewejohann, L. 2019. Assessing affective state in laboratory rodents to promote animal welfare—What is the progress in applied refinement research? Animals 9(12), 1026.

In the past, there was a strong focus on avoiding or reducing negative animal welfare in animal experimentation. Recently, the importance of promoting positive animal welfare in laboratory animals has been highlighted. To ensure and...

McMillan, F. D. (ed). 2019. Mental Health and Well-being in Animals (2nd ed). CABI, Wallingford, UK.

This second edition is fully revised, expanded, and comprehensively updated with the most current knowledge about the full array of mental health issues seen in animals. Written by key opinion leaders, internationally-recognized experts and specialists...

Makowska, I. J., Weary, D. M. 2019. A good life for laboratory rodents? ILAR Journal 60(3), 373-388.

Most would agree that animals in research should be spared “unnecessary” harm, pain, or distress, and there is also growing interest in providing animals with some form of environmental enrichment. But is this the standard...

Machado, M., Oliveira da Silva, I. J. 2019. Does farm animals experience emotions and feelings? Journal of Animal Behaviour and Biometeorology 7(4), 170-175.

In recent years, there has been a great increase in the interest of "emotion" and how it can be studied and translated from animals. Emotions arise when the brain receives an external stimulus, while the...

Fischer, C. P., Romero, L. M. 2019. Chronic captivity stress in wild animals is highly species-specific. Conservation Physiology 7(1), coz093.

Wild animals are brought into captivity for many reasons—conservation, research, agriculture and the exotic pet trade. While the physical needs of animals are met in captivity, the conditions of confinement and exposure to humans can...

Špinka, M. 2019. Animal agency, animal awareness and animal welfare. Animal Welfare 28(1), 11–20.

In nature, animals need to actively engage with the environment in order to prosper in survival and reproduction. Hence, agency is a central adaptive characteristic of animal life. In this paper, I propose that from...

Eusemann, B. K., Baulain, U., Schrader, L. et al. 2018. Radiographic examination of keel bone damage in living laying hens of different strains kept in two housing systems. PLOS ONE 13(5), e0194974.

A high prevalence of deviations and fractures of the keel bone is a widespread welfare problem in laying hens. The aim of this study was to experimentally investigate this multifactorial problem throughout the laying period...

Riddle, E. R., Ali, A. B. A., Campbell, D. L. M. et al. 2018. Space use by 4 strains of laying hens to perch, wing flap, dust bathe, stand and lie down. PLOS ONE 13(1), e0190532.

The laying hen industry is implementing aviary systems intended to improve welfare by providing hens with more space and resources to perform species-specific behaviors. To date, limited research has examined spatial requirements of various strains...

Funkhouser, J. A., Mayhew, J. A., Mulcahy, J. B. 2018. Social network and dominance hierarchy analyses at Chimpanzee Sanctuary Northwest. PLOS ONE 13(2), e0191898.

Different aspects of sociality bear considerable weight on the individual- and group-level welfare of captive nonhuman primates. Social Network Analysis (SNA) is a useful tool for gaining a holistic understanding of the dynamic social relationships...

Jansson, D.S. 2018 Gaining insights into the health of non-caged layer hens. Veterinary Record 182(12), 347-349.

To prevent injuries and mortality in commercial non-caged laying hens a range of strategies should be used, including vaccination, effective biosecurity routines, optimal management and nutrition. Injurious pecking, footpad lesions, keel bone fractures, reproductive and...

Tallent, B. R., Law, L. M., Rowe, R. K. et al. 2018. Partial cage division significantly reduces aggressive behavior in male laboratory mice. Laboratory Animals 52(4), 384 - 393.

Aggression in mice often results in injury leading to unplanned euthanasia or the initiation of protocols to isolate animals, thereby increasing research costs and straining resources. Here, we tested if adding a partial cage divider...

Chen, S., Xiang, H., Zhu, X. et al. 2018. Free dietary choice and free-range rearing improve the product quality, gait score, and microbial richness of chickens. Animals 8(6), 84.

Poultry welfare has been extensively studied; however, there is a lack of rigorous scientific knowledge relating to the different aspects of welfare factors and how this may contribute to the production quantity and product quality...

Chuppava, B., Visscher, C., Kamphues, J. 2018. Effect of different flooring designs on the performance and foot pad health in broilers and turkeys. Animals 8(5), 70.

Litter quality has a significant influence on the performance and foot pad health in poultry. The objective of this study was to evaluate the effects of different types of flooring designs on the performance and...

Neal Webb, S. J., Hau, J., Schapiro, S. J. 2018. Captive chimpanzee (Pan troglodytes) behavior as a function of space per animal and enclosure type. American Journal of Primatology 80(2), e22749.

Space per animal, or animal density, and enclosure type are important elements of functionally appropriate captive environments (FACEs) for chimpanzees. The National Institutes of Health (NIH) recommends that captive chimpanzees be maintained in areas of...

Yamanashi, Y., Teramoto, M., Morimura, N. et al. 2018. Social relationship and hair cortisol level in captive male chimpanzees (Pan troglodytes). Primates 59(2) 145-152.

Understanding how social relationships affect long-term stress is important because stress has a profound impact on the welfare of animals and social relationships often exert a strong influence on their stress responses. The purpose of...