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. 
Zhang, J., Yu, L., Yin, G. 2022. Evaluation of behavior and affective state of different-parity sows with strong/weak pupil light reflex. Animals 12(9), 1184.

The stall-housing system is commonly used in the modern swine industry in many countries; however, long-term space restrictions can cause affective and physiological abnormalities in sows. The pupil light reflex (PLR) can reflect the psychological...

Son, J., Lee, W.-D., Kim, H.-J. et al. 2022. Effect of providing environmental enrichment into aviary house on the welfare of laying hens. Animals 12(9), 1165.

This study aimed to determine the effects of providing environmental enrichment materials—pumice stone and alfalfa hay—to laying hens in the aviary system. A total of 2196 40-week-old Hy-Line Brown laying hens were randomly allotted to...

Li, S., Hu, H., Huang, J. et al. 2022. Effect of enrichment items on the physiology and behavior of sows in the third trimester of pregnancy. Animals 12(11), 1355.

Modern intensive pig breeding harms animal welfare, which is especially noticeable for pregnant sows kept in confinement stalls. This study aimed to evaluate the effects of enrichment items on the movement and physiological parameters of...

Knaebe, B., Weiss, C. C., Zimmermann, J. et al. 2022. The promise of behavioral tracking systems for advancing primate animal welfare. Animals 12(13), 1648.

Recent years have witnessed major advances in the ability of computerized systems to track the positions of animals as they move through large and unconstrained environments. These systems have so far been a great boon...

Roy, C., Kyeiwaa, V., Mancera, K. F. et al. 2022. Effects of enrichment type, presentation and social status on enrichment use and behavior of sows—Part 2: Free access stall feeding. Animals 12(14), 1768.

Continuing with previous research by our group in an ESF system, four types of enrichment treatments were assessed in gestating sows housed in Free Access Stalls: (1) Constant: constant provision of wood on chain; (2)...

Ramankevich, A., Wengerska, K., Rokicka, K. et al. 2022. Environmental enrichment as part of the improvement of the welfare of Japanese quails. Animals 12(15), 1963.

The aim of this study was to evaluate the indicators of the behavioural and physiological welfare of Japanese quails (Coturnix japonica) as possible responses to the enrichment of the birds’ habitat. The study sample consisted...

Lou, M. E., Porter, S. T., Massey, J. S. et al. 2022. The application of 3D landmark-based geometric morphometrics towards refinement of the piglet grimace scale. Animals 12(15), 1944.

Proper methods of assessment to objectively identify pain are essential for welfare improvements of piglets undergoing surgical castration on commercial farms. The Piglet Grimace Scale (PGS) is used to identify changes in facial expressions caused...

Paterson, E. A., Turner, P. V. 2022. Challenges with assessing and treating pain in research primates: A focused survey and literature review. Animals 12(17), 2304.

Research primates may undergo surgical procedures making effective pain management essential to ensure good animal welfare and unbiased scientific data. Adequate pain mitigation is dependent on whether veterinarians, technicians, researchers, and caregivers can recognize and...

Lippi, I. C. de C., Caldara, F. R., Almeida-Paz, I. C. de L. et al. 2022. Effects of music therapy on neuroplasticity, welfare, and performance of piglets exposed to music therapy in the intra- and extra-uterine phases. Animals 12(17), 2211.

The rearing environment of pigs can cause a high level of stress due to the lack of stimuli and the impossibility of carrying out natural behaviors. Music therapy is a way to enrich the environment...

Drexl, V., Dittrich, I., Haase, A. et al. 2022. Tail posture as an early indicator of tail biting - A comparison of animal and pen level in weaner pigs. Applied Animal Behaviour Science 252, 105654.

The occurrence of tail biting is one of the most important animal welfare problems in pig farming and needs to be recognised early to reduce injuries and suffering. The posture of the tail could be...

Vasdal, G., Gebhardt-Henrich, S. G., Tahamtani, F. et al. 2022. Perch use in commercial broiler breeders – Preference for perch material and effect of age. Applied Animal Behaviour Science 253, 105680.

Unlike for laying hens in most European countries, few broiler breeders have access to perches, and there is a need for more knowledge on perching behavior in broiler breeders. The aim of this study was...

Aldhshan, M. S., Mizuno, T. M. 2022. Effect of environmental enrichment on aggression and the expression of brain-derived neurotrophic factor transcript variants in group-housed male mice. Behavioural Brain Research 433, 113986.

Social and environmental factors influence behavior via modulation of brain physiological functions. Environmental enrichment (EE) is an animal housing technique that provides complex sensory, motor, and social stimulation, leading to modifications in the innate aggressiveness...

Mieske, P., Hobbiesiefken, U., Fischer-Tenhagen, C. et al. 2022. Bored at home?—A systematic review on the effect of environmental enrichment on the welfare of laboratory rats and mice. Frontiers in Veterinary Science 9, 899219.

Boredom is an emotional state that occurs when an individual has nothing to do, is not interested in the surrounding, and feels dreary and in a monotony. While this condition is usually defined for humans...

Slocum, S. K., Morris, K. L. 2022. Assessing preference in a paired-stimulus arrangement with captive vultures (Aegypius monachus). Journal of Applied Animal Welfare Science 25(4), 362-367.

Vultures play an important role in our ecosystem by filtering out bacteria and viruses harmful to humans (e.g., rabies, botulism). However, many vultures remain in human care due to skill deficits and behavioral excesses, which...

Alaniz, A. J., Astudillo-Hinojosa, K., Soto, A. F. et al. 2022. Rapid behavioral recovery based on environmental enrichment of a white-throated toucan (Ramphastos tucanus: Ramphastidae) affected by collision trauma. Journal of Veterinary Behavior 57, 1-5.

Captive animals that have experienced traumatic events require a high range of care prior to reintroducing them into their natural habitat; and this care should ensure their welfare in captivity. This report shows the ethological...

Snipes, M. M., Wofford, K. A., Funk, A. L. et al. 2022. Modernization of wall guard railing for safe enrichment in feline housing facilities. Laboratory Animal Science Professional 10(5) (September/October), 50-51.

Creatively adapting older lab animal housing spaces to improve psychological well-being, welfare, and safety for animals is necessary to meet expectations for animal enrichment. Traditional lab animal facilities are designed to have functional, flexible, durable...

Ramírez-Rodríguez, G. B., Gutiérrez-Vera, B., Ortiz-López, L. et al. 2022. Environmental enrichment: Dissociated effects between physical activity and changing environmental complexity on anxiety and neurogenesis in adult male Balb/C mice. Physiology & Behavior 254, 113878.

Several factors, including environmental modifications, stimulate neuroplasticity. One type of neuroplasticity consists in the generation of new neurons in the dentate gyrus of the hippocampus. Neurogenesis is modulated by environmental enrichment (ENR, tunnels plus running...

Spitzer, H. B., Meagher, R. K., Proudfoot, K. L. 2022. The impact of providing hiding spaces to farmed animals: A scoping review. PLOS ONE 17(11), e0277665.

Many wild animals perform hiding behaviours for a variety of reasons, such as evading predators or other conspecifics. Unlike their wild counterparts, farmed animals often live in relatively barren environments without the opportunity to hide...

Guevara, R. D., Pastor, J. J., Manteca, X. et al. 2022. Systematic review of animal-based indicators to measure thermal, social, and immune-related stress in pigs. PLOS ONE 17(5), e0266524.

The intense nature of pig production has increased the animals’ exposure to stressful conditions, which may be detrimental to their welfare and productivity. Some of the most common sources of stress in pigs are extreme...

MacLellan, A., Nazal, B., Young et al. 2022. Waking inactivity as a welfare indicator in laboratory mice: Investigating postures, facial expressions and depression-like states. Royal Society Open Science 9(11), 221083.

Animal welfare assessment relies on valid and practical indicators of affect. In mice, the most widely used research vertebrates, lying still with eyes open, inactive-but-awake (IBA) in the home cage, has potential to be one...

Eagan, B. H., Eagan, B., Protopopova, A. 2022. Behaviour real-time spatial tracking identification (BeRSTID) used for cat behaviour monitoring in an animal shelter. Scientific Reports 12(1), 17585.

Efficiently tracking animal behaviour in an animal shelter has direct lifesaving applications. Individualized care and early recognition of distress in cats are often missed. However, monitoring behaviour is a challenge as time and financial resources...

Kleiber, A., Le-Calvez, J. M., Kerneis, T. et al. 2022. Positive effects of bubbles as a feeding predictor on behaviour of farmed rainbow trout. Scientific Reports 12(1), 11368.

Occupational enrichment emerges as a promising strategy for improving the welfare of farmed animals. This form of enrichment aims to stimulate cognitive abilities of animals by providing them with more opportunities to interact with and...

Feighelstein, M., Shimshoni, I., Finka, L. R. et al. 2022. Automated recognition of pain in cats. Scientific Reports 12(1), 9575.

Facial expressions in non-human animals are closely linked to their internal affective states, with the majority of empirical work focusing on facial shape changes associated with pain. However, existing tools for facial expression analysis are...

Parois, S. P., Van Der Zande, L. E., Knol, E. F. et al. 2022. A multi-suckling system combined with an enriched housing environment during the growing period promotes resilience to various challenges in pigs. Scientific Reports 12(1), 6804.

Little is known about the impact of social and environmental enrichment on improving livestock resilience, i.e. the ability to quickly recover from perturbations. We evaluated the effect of an alternative housing system (AHS) on resilience...

Archer, C., Garcia, A., Henderson, M. et al. 2022. Olfactory enrichment using a maternal pheromone improved post-weaning pig performance and behavior. Frontiers in Veterinary Science 9, 965370.

The post-weaning environment in commercial pig nursery buildings is typically devoid of both the sow and her semiochemicals. Among other factors, the loss of maternal odors may contribute to post-weaning stress. In this work, we...