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. 
Zepp, M., Louton, H., Erhard, M. et al. 2018. The influence of stocking density and enrichment on the occurrence of feather pecking and aggressive pecking behavior in laying hen chicks. Journal of Veterinary Behavior 24, 9-18.

The housing conditions and environments experienced during the rearing period can influence the development of feather pecking in chickens during this time and in the subsequent laying period. The aim of this study was to...

Heyworth, C., Olivo, D. 2018. Environmental and psychological enrichment for NHPs reimagined and repurposed. Laboratory Animal Science Professional 5(4) (December), 39-43.

This article describes creative enrichment ideas for nonhuman primates, including celery stalks embedded with seeds; paper rolled into tubes, braided and filled with fruit and seeds; pineapple crowns loaded with treats; dry spaghetti noodles coated...

Volkmann, J. L., Evans, C. A., Buckmaster, C. 2018. Pigeons: Flying to new heights. Laboratory Animal Science Professional 6(1) (March), 33-34.

When singly or pair housed in cages, pigeons have a relatively small area in which to walk and stretch or flap their wings. More space is required to allow pigeons to be housed in numbers...

Unakafov, A. M., Möller, S., Kagan, I. et al. 2018. Using imaging photoplethysmography for heart rate estimation in non-human primates. PLOS ONE 13(8), e0202581.

For humans and for non-human primates heart rate is a reliable indicator of an individual’s current physiological state, with applications ranging from health checks to experimental studies of cognitive and emotional state. In humans, changes...

Wallace, E. K., Altschul, D., Körfer, K. et al. 2017. Is music enriching for group-housed captive chimpanzees (Pan troglodytes)? PLOS ONE 12(3), e0172672.

Many facilities that house captive primates play music for animal enrichment or for caregiver enjoyment. However, the impact on primates is unknown as previous studies have been inconclusive. We conducted three studies with zoo-housed chimpanzees...

Palmer, S. 2017. Rescue-Enrich-Release: The environmental enrichment program for three species of captive primates at Colobus. Canopy 17(2), 27-30.

It is widely known that the psychological wellbeing of captive animals can become compromised by a captive environment that lacks proper environmental stimulation. Environmental enrichment programs have become the norm in captive environments yet research...

Alligood, C. A., Dorey, N. R., Mehrkam, L. R. et al. 2017. Applying behavior-analytic methodology to the science and practice of environmental enrichment in zoos and aquariums. Zoo Biology 36(3), 175–185.

Environmental enrichment in zoos and aquariums is often evaluated at two overlapping levels: published research and day‐to‐day institutional record keeping. Several authors have discussed ongoing challenges with small sample sizes in between‐groups zoological research and...

Nelson Slater, M., Hauber, M. E. 2017. Olfactory enrichment and scent cue associative learning in captive birds of prey. Zoo Biology 36(2), 120–126.

As the use of enrichment in zoos has become a standardized husbandry practice, the continued improvement of enrichment programs should be concomitant with empirical validation of those practices. The role of scent as enrichment remains...

Carlson, A., Allen, C., Skoumbourdis, E. et al. 2017. Cooked food for non-human primates: A discussion by the Laboratory Animal Refinement & Enrichment Forum. Animal Technology and Welfare 16(2), 124-126.

"Do any of you give cooked food like pasta, potatoes or vegetables to non-human primates? What’s your experience? Do the animals benefit from cooked food; do they like it; does it affect their health in...

Spiezio, C., Leonardi, C., Regaiolli, B. 2017. Assessing colour preference in Aldabra giant tortoises (Geochelone gigantea). Behavioural Processes 145, 60-64.

Tortoises perceive different colours and rely on the visual system to find food. However, few studies have considered colour preference in tortoises, especially in land species. The aim of this study is to investigate whether...

Buckley, D. P., Duggan, M. R., Anderson, M. J. 2017. Budgie in the mirror: An exploratory analysis of social behaviors and mirror use in the Budgerigar (Melopsittacus undulatus). Behavioural Processes 135, 66-70.

Despite their prevalent use amongst avian species, particularly in Budgerigars, the relationship between mirror use and social behaviors is in need of elucidation. After establishing social behavior measures (e.g., agonistic and pair-bond data) in a...

Coleman, K., Novak, M. A. 2017. Environmental enrichment in the 21st century. ILAR Journal 58(2), 295-307.

More than a quarter of a century has elapsed since the Animal Welfare Act mandated that research facilities develop and follow a plan to promote the psychological well-being of captive primates. Since passage of this...

Williams, I., Hoppitt, W., Grant, R. 2017. The effect of auditory enrichment, rearing method and social environment on the behavior of zoo-housed psittacines (Aves: Psittaciformes); implications for welfare. Applied Animal Behaviour Science 186, 85-92.

The psychological and physiological effects of different genres of music are well documented in humans. These concepts have also been studied in kenneled dogs and some exotic animals, implying that animals may experience benefits similar...

Liu, K., Xin, H. 2017. Effects of horizontal distance between perches on perching behaviors of Lohmann Hens. Applied Animal Behaviour Science 194, 54-61.

Perching is a highly-motivated natural behavior of laying hens that has been considered as one of the essential welfare requirements. The objective of the study was to evaluate perching behaviors of laying hens as affected...

Brantsæter, M., Tahamtani, F. M., Nordgreen, J. et al. 2017. Access to litter during rearing and environmental enrichment during production reduce fearfulness in adult laying hens. Applied Animal Behaviour Science 189, 49-56.

Exaggerated fear-reactions are associated with injurious flying, smothering, feather pecking and other events that compromise animal welfare in laying hens. The aim of this study was to test the hypothesis that chicks with access to...

Hunniford, M. E., Widowski, T. M. 2017. Nest alternatives: Adding a wire partition to the scratch area affects nest use and nesting behaviour of laying hens in furnished cages. Applied Animal Behaviour Science 186, 29-34.

Furnished cages (FC) are designed to accommodate highly motivated behaviour patterns like nesting; however, how hens perceive the resources provided in FCs is not fully understood. Our previous research of hens in FCs with a...

Pettersson, I. C., Weeks, C. A., Nicol, C. J. 2017. The effect of ramp provision on the accessibility of the litter in single and multi-tier laying hen housing. Applied Animal Behaviour Science 186, 35-40.

Level changes in commercial laying hen loose-housing systems may be physically difficult for birds to negotiate, preventing or limiting access to resources such as the litter area and the outdoor range, and potentially increasing injury...

Pettersson, I. C., Weeks, C. A., Nicol, C. J. 2017. Provision of a resource package reduces feather pecking and improves ranging distribution on free-range layer farms. Applied Animal Behaviour Science 195, 60-66.

The effect of a resource package designed to reduce inter-bird pecking and increase range use was tested on fourteen free-range farms in the UK. The package comprised two types of objects intended to attract pecking...

Keeling, L. J., Newberry, R. C., Estevez, I. 2017. Flock size during rearing affects pullet behavioural synchrony and spatial clustering. Applied Animal Behaviour Science 194, 36-41.

Animals are often synchronised in their behaviour, with costs and benefits varying according to group size and the behaviour being performed. Making decisions about optimal allocation and distribution of resources to animals in our care...

Stadig, L. M., Rodenburg, T. B., Ampe, B. et al. 2017. Effect of free-range access, shelter type and weather conditions on free-range use and welfare of slow-growing broiler chickens. Applied Animal Behaviour Science 192, 15-23.

Free-range access for broiler chickens can benefit animal welfare because the birds have access to a more natural environment and more opportunities to perform natural behaviours than in indoor systems. Also, they have more space...

Rault, J.-L., Taylor, P. S. 2017. Indoor side fidelity and outdoor ranging in commercial free-range chickens in single- or double-sided sheds. Applied Animal Behaviour Science 194, 48-53.

The ranging behaviour of broiler chickens kept in free-range housing systems remains poorly understood, despite access to the outdoor range being their main feature. We investigated the impact of allowing chickens to have range access...

Meng, F., Chen, D., Li, X. et al. 2017. The effect of large or small furnished cages on behaviors and tibia bone of laying hens. Journal of Veterinary Behavior 17, 69-73.

This study aimed to investigate the effects of large furnished cages (LFCs) or small furnished cages (SFCs) on behavior and tibia bone of laying hens. Three hundred and sixty Hyline brown hens at 16 weeks...

Greenwell, P. J., Montrose, V. T. 2017. The gray matter: Prevention and reduction of abnormal behavior in companion gray parrots (Psittacus erithacus). Journal of Veterinary Behavior 20, 44-51.

Gray parrots (Psittacus erithacus) are popular companion birds, particularly noted for their ability to mimic human speech, their intelligence, and longevity. They are also prone to developing abnormal behaviors such as feather damaging behavior. This...

Sands, C., Evans, C., Buckmaster, C. A. 2017. The grooming sleeve: Encouraging conspecific-like behavior and strengthening the human-animal bond. Laboratory Animal Science Professional 5(2) (June), 52-53.

The act of grooming has been found to greatly decrease stress, heart rate, and cortisol levels in nonhuman primates; this decrease in stress and cortisol is seen in the animal being groomed, as well as...

Monreal-Pawlowsky, T., Marco-Cabedo, V., Manteca, X. et al. 2017. Environmental enrichment facilitates release and survival of an injured loggerhead sea turtle (Caretta caretta) after ten years in captivity. Journal of Zoo and Aquarium Research 5(4), 182-186.

In June 2006 a loggerhead sea turtle (Caretta caretta) was admitted to a rescue centre on the Mediterranean coast with severe fishing net entanglement in its fore right flipper. The flipper could not be saved...