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. 
Travain, T., Valsecchi, P. 2021. Infrared thermography in the study of animals’ emotional responses: A critical review. Animals 11(9), 2510.

Whether animals have emotions was historically a long-lasting question but, today, nobody disputes that they do. However, how to assess them and how to guarantee animals their welfare have become important research topics in the...

Padrell, M., Amici, F., Córdoba, M. P. et al. 2021. Artificial termite-fishing tasks as enrichment for sanctuary-housed chimpanzees: Behavioral effects and impact on welfare. Animals 11(10), 2941.

Artificial termite-fishing tasks are a common enrichment for captive great apes, promoting species-typical behaviors. Nonetheless, whether these activities are linked to changes in other behaviors and whether these changes persist over time has seldom been...

Kalies, A., Baumgartner, J., Beyerbach, M. et al. 2021. Interactive rooting towers and behavioural observations as strategies to reduce tail biting on conventional pig fattening farms. Animals 11(11), 3025.

Eight pens (25 pigs/pen; n = 200) provided with an interactive straw-filled rooting tower (experimental group) and five pens (25 pigs/pen; n = 125) with a stationary (fixed) tower without straw (control group) were compared...

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...

Fynn, M., Crow, G., Connor, L. 2021. Pre-farrow enrichment with burlap sheet: potential benefit for sow performance. Canadian Journal of Animal Science 101(4), 781-787.

Burlap has been proposed as an enrichment option for the conventional farrowing crate environment. Our objectives were to determine if burlap sheets hung in farrowing crates were used by sows and piglets and had any...

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...

Schodl, K., Wiesauer, L., Winckler, C. et al. 2021. Reduced stocking density and provision of straw in a rack improve pig welfare on commercial fattening farms. Frontiers in Veterinary Science 8, 656211.

The aim of this study was to investigate the impact of reduced stocking density in combination with provision of additional enrichment material on pig welfare on-farm. On three growing-finishing farms in Austria, in total 974...

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...

Krugmann, K. L., Mieloch, F. J., Krieter, J. 2021. Can tail and ear postures be suitable to capture the affective state of growing pigs? Journal of Applied Animal Welfare Science 24(4), 411-423.

The present study examined whether tail and ear postures in fattening pigs (n = 228) housed in different environments could be suitable for assessing their affective state. In doing so, it investigated the appearance of...

Vinícius dos Santos, J., de Souza Farias, S., Pereira, T. L. et al. 2021. Preference for and maintenance of interest in suspended enrichment toys in confined growing pigs. Journal of Veterinary Behavior 45, 68-73.

The objective of the present study was to evaluate the preference for, interest in, and behavior of growing pigs provided with three different suspended enrichment toys in a four-compartment environmental preference chamber (EPC). Sixty pigs...

Monreal-Pawlowsky, T., Vaicekauskaitė , R., Palencia Membrive, G. et al. 2021. Goal-oriented behavioural and environmental enrichment in aquarium species. Journal of Zoo and Aquarium Research, 9(4), 273-280.

Environmental enrichment is a common tool used in zoo and aquarium settings to provide mental and physical stimulation to animals under human care. This paper aims to present a primary approach to goal-oriented environmental and...

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.

Merley, A. L., Duke Boynton, F. D. 2021. Design and construction of a low-cost mirror for enrichment of socially isolated pigs. Laboratory Animal Science Professional 9(5) (September/October), 56-57.

Due to their social needs, every effort should be made to house pigs with compatible conspecifics; however, there may be instances where due to experimental or veterinary concerns, single housing is necessary. In those situations...

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.

Vining, A. Q., Nunn, C. L., Samson, D. R. 2021. Enriched sleep environments lengthen lemur sleep duration. PLOS ONE 16(11), e0253251.

Characteristics of the sleep-site are thought to influence the quality and duration of primate sleep, yet only a handful of studies have investigated these links experimentally. Using actigraphy and infrared videography, we quantified sleep in...

Janhunen, M., Piironen, J., Vainikka, A. et al. 2021. The effects of environmental enrichment on hatchery-performance, smolt migration and capture rates in landlocked Atlantic salmon. PLOS ONE 16(12), e0260944.

Enrichment of rearing environment with natural elements has been suggested to improve the welfare and post-release survival of cultured fish. We studied the combined effects of shelter structures, periodical water flow and water level changes...

Brooks, J., Yoshimura, H., Taki, Y. 2021. Knowledge-based enrichment: Development of a novel enrichment device for captive chimpanzees. Zoo Biology 40(5), 398-406.

The field of environmental enrichment has grown considerably, but most enrichment is still focused on tasks where highly valued food rewards are directly visible. We designed a device which would instead make use of knowledge...

Misra, S., Bokkers, E., Upton, J. et al. 2021. Effect of environmental enrichment and group size on the water use and waste in grower-finisher pigs. Scientific Reports 11(1), 16380.

The grower-finisher stage accounts for 64% of the total on-farm herd water use. Part of this is consumed by the pigs, but a part is also wasted. Drinking water usage and wastage is affected by...

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...

Laméris, D. W., Verspeek, J., Depoortere, A. et al. 2021. Effects of enclosure and environmental enrichment on the behaviour of ring-tailed lemurs (Lemur catta). Journal of Zoological and Botanical Gardens 2(2), 164–173.

Environmental enrichment is widely used to improve the quality of life of animals under human care. To successfully implement enrichment programs, it is important to evaluate their effect in different enclosure types since housing conditions...

Goldsborough, Z., van Leeuwen, E. J. C., Kolff, K. W. T. et al. 2020. Do chimpanzees (Pan troglodytes) console a bereaved mother? Primates volume 61(1), 93–102.

Comparative thanatology encompasses the study of death-related responses in non-human animals and aspires to elucidate the evolutionary origins of human behavior in the context of death. Many reports have revealed that humans are not the...

Sharma, N., Sharma Pokharel, S., Kohshima S. et al. 2020. Behavioural responses of free-ranging Asian elephants (Elephas maximus) towards dying and dead conspecifics. Primates 61(1), 129–138.

Reactions to dying and dead conspecifics have been observed in many non-human animals. Elephants, particularly African elephants, are thought to have an awareness of the death of their conspecifics, as they show compassionate behaviour towards...

Sandgrav Bak, A., Malmkvist, J. 2020. Barren housing and negative handling decrease the exploratory approach in farmed mink. Applied Animal Behaviour Science 222, 104901.

We examined the influence of cage enrichment and different types of short-term experiences on the temperament of farmed mink. We used juvenile Palomino mink (n = 600, housed in pairs of one male and one female) in...

Matsuzawa, T. 2020. WISH cages: Constructing multiple habitats for captive chimpanzees. Primates 61(2), 139–148.

This article aims to introduce environmental enrichment for captive chimpanzees in Japan in a historical context. It describes the most recent endeavor of constructing huge cages and connecting multiple habitats. The Ai Project, a series...

Skalníková, P., Frynta, D., Abramjan, A. et al. 2020. Spontaneous color preferences in rhesus monkeys: What is the advantage of primate trichromacy? Behavioural Processes 174, 104084.

Color perception and color signaling play an important role in various aspects of animal behavior. However, in mammals, trichromatic vision characterized by three retinal photopigments tuned to peak short, middle and long wavelengths is limited...