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. 
Crump, A., Gibbons, M., Barrett, M. et al. 2023. Is it time for insect researchers to consider their subjects’ welfare? PLOS Biology 21(6), e3002138.

Recent evidence suggests that at least some insect species might plausibly feel pain. These findings should prompt researchers to think about the welfare implications of insect experiments.

Evans, L., Brooks, G. C., Anderson, M. G. et al. 2023. Environmental complexity and reduced stocking density promote positive behavioral outcomes in broiler chickens. Animals 13(13), 2074.

The objective was to evaluate the impacts of a complex environment and stocking density on Ross 708 broiler chicken behaviors. Eight pens contained either high complexity (HC) or low complexity (LC) environments, and high (HD)...

Mauthe von Degerfeld, M., Serpieri, M., Bonaffini, G. et al. 2023. Intranasal atomization of ketamine, medetomidine and butorphanol in pet rabbits using a mucosal atomization device. Animals 13(13), 2076.

A non-invasive method of drug delivery, intranasal atomization, has shown positive results in human medicine and in some animal species. The objective of this study was to evaluate the effects of intranasal atomization, compared to...

Andersen, I. L., Ocepek, M., Thingnes, S. L. et al. 2023. Welfare and performance of finishing pigs on commercial farms: Associations with group size, floor space per pig and feed type. Applied Animal Behaviour Science 265, 105979.

Based on data from a field survey of 85 Norwegian farms, we aimed to investigate associations of group size, floor space per pig and type of feed with selected welfare- and performance indicators in finishing...

Contreras-Jodar, A., Escribano, D., Cerón, J. J. et al. 2023. Reducing stocking densities and using cooling systems for more adapted pigs to high temperatures when reared in intensive conditions. Animals 13(15), 2424.

This study is aimed at evaluating the effect of reducing stocking density and using cooling systems to mitigate the negative effects of high temperatures in growing pigs (females and castrated males) reared in intensive conditions...

Elwood, R. W. 2023. Behavioural indicators of pain and suffering in arthropods and might pain bite back? Animals 13(16), 2602.

Pain in response to tissue damage functions to change behaviour so that further damage is minimised whereas healing and survival are promoted. This paper focuses on the behavioural criteria that match the function to ask...

Farnsworth, K. D., Elwood, R. W. 2023. Why it hurts: With freedom comes the biological need for pain. Animal Cognition 26(4), 1259–1275.

We argue that pain is not needed to protect the body from damage unless the organism is able to make free choices in action selection. Then pain (including its affective and evaluative aspects) provides a...

Zhang, Y., Yu, J., Zhang, Y. et al. 2023. Emotional contagion and social support in pigs with the negative stimulus. Animals 13(20), 3160.

This study expects to confirm the existence of emotional transmission in pigs from multiple perspectives and to provide theoretical references for improving animal welfare in livestock farming. A group that could directly observe (DO) and...

Mocz, F., Michel, V., Janvrot, M. et al. 2022. Positive effects of elevated platforms and straw bales on the welfare of fast-growing broiler chickens reared at two different stocking densities. Animals 12(5), 542.

In conventional rearing systems, fast-growing broiler chickens commonly experience welfare issues, such as contact dermatitis, walking difficulties or a lack of expression of species-specific behaviours. Enriching their environment may be a way to improve their...

Stephenson, E., Haskell, M. J. 2022. The use of a “go/go” cognitive bias task and response to a novel object to assess the effect of housing enrichment in sheep (Ovis aries). Journal of Applied Animal Welfare Science 25(1), 62-74.

It is widely acknowledged that environmental enrichment can improve animals’ welfare and emotional state. This study used cognitive bias and response to a novel object to assess the effect of enriched housing on emotional state...

Zapata Cardona, J., Ceballos, M. C., Tarazona Morales, A. M. et al. 2022. Music modulates emotional responses in growing pigs. Scientific Reports 12(1), 3382.

There is a lack of clarity on whether pigs can emotionally respond to musical stimulation and whether that response is related to music structure. Qualitative Behavioral Assessment (QBA) was used to evaluate effects of 16...

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...

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...

Houstin, A., Zitterbart, D. P., Winterl, A. et al. 2022. Biologging of emperor penguins—Attachment techniques and associated deployment performance. PLOS ONE 17(8), e0265849.

An increasing number of marine animals are equipped with biologgers, to study their physiology, behaviour and ecology, often for conservation purposes. To minimise the impacts of biologgers on the animals’ welfare, the Refinement principle from...

Hamlaoui, A., Keeling, L., Burman, O. et al. 2022. Investigating attentional scope as a novel indicator of emotional state in animals. Scientific Reports 12(1), 17452.

In humans, contrasting emotional states can lead to a broadening or narrowing of attentional scope. Whether this is also the case in animals has yet to be investigated. If confirmed, measurement of attentional scope has...

Mayes, B. T., Tait, L. A., Cowley, F. C. et al. 2022. Stocking density, restricted trough space, and implications for sheep behaviour and biological functioning. Frontiers in Veterinary Science 9, 965635.

Stocking density and trough space allowance can potentially impact sheep welfare during live export voyages. The aim of this study was to assess the welfare implications for sheep housed at five allometric stocking densities, with...

Schwarzer, A., Erhard, M., Schmidt, P. et al. 2022. Effects of stocking rate and environmental enrichment on the ontogeny of pecking behavior of laying hen pullets confined in aviary compartments during the first 4 weeks of life. Animals 12(19), 2639.

The objective of this study was to describe the ontogeny of the severe feather pecking (SFP), gentle feather pecking (GFP), aggressive pecking (AP), and enrichment pecking (EP) of non-beak-trimmed Lohmann Brown (LB)-pullets during the first...

Serrano, C., Antonio, J. 2022. Ultrasound guided surgery as a refinement tool in oncology research. Animals 12(23), 3445.

Refinement is one of the ethical pillars of the use of animals in research. Ultrasonography is currently used in human medicine as a surgical tool for guided biopsies and this idea can be applied to...

Wilson, C. H., Wyeth, R. C., Spicer, J. I. et al. 2022. Effect of animal stocking density and habitat enrichment on survival and vitality of wild green shore crabs, Carcinus maenas, maintained in the laboratory. Animals 12(21), 2970.

The wide geographic distribution, large size and ease of capture has led to decapod crustaceans being used extensively in laboratory experiments. Recently in the United Kingdom decapod crustaceans were listed as sentient beings, resulting in...

Zablocki-Thomas, P. B., Rogers, F. D., Bales, K. L. 2022. Neuroimaging of human and non-human animal emotion and affect in the context of social relationships. Frontiers in Behavioral Neuroscience 16, 994504.

Long-term relationships are essential for the psychological wellbeing of humans and many animals. Positive emotions and affective experiences (e.g., romantic or platonic love) seem to be closely related to the creation and maintenance of social...

van der Eijk, J. A. J., Gunnink, H., Melis, M. et al. 2022. Reducing stocking density benefits behaviour of fast- and slower-growing broilers. Applied Animal Behaviour Science 257, 105754.

The broiler industry has come under sustained pressure from welfare organizations to improve broiler welfare. Breed and stocking density are important factors for broiler welfare and are often specified as criteria for higher welfare systems...

Briffa, M. 2022. When should we ascribe sentience to animals? A commentary on “Hermit crabs, shells and sentience” (Elwood 2022). Animal Cognition 25(6), 1375–1380.

In a new review article, experiments on hermit crab behaviour are discussed in the context of possible animal sentience. Sentience can be defined as the ability to experience feelings such as pleasure or pain but...

Elwood, R. W. 2022. Caution is required when considering sentience in animals: A response to the commentary by Briffa (2022) on “Hermit crabs, shells, and sentience” (Elwood 2022). Animal Cognition 25(6), 1371–1374.

My recent review examined the complex and intimate relationship between hermit crabs and the empty gastropod shells upon which they depend for survival. Because shells come with costs as well as benefits, the crabs are...

Elwood, R. W. 2022. Hermit crabs, shells, and sentience. Animal Cognition 25(5), 1241–1257.

Hermit crabs have an intimate relationship with gastropod shells and show numerous activities by which they locate, select, and change shells in different contexts. They gather information about new shells and update information about their...

Takahashi, K. 2022. Changes in the anxiety-like and fearful behavior of shrimp following daily threatening experiences. Animal Cognition 25(2), 319–327.

Behavioral variation in animals is often influenced by experience. Previous studies have found that daily threatening experiences can enhance fear- and anxiety-like behaviors in some vertebrates. However, it is unclear whether the change in fear/anxiety...