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. 
Chakkingal Bhaskaran, B., Meyermans, R., Gorssen, W. et al. 2023. A comparative study on the effect of euthanasia methods and sample storage conditions on RNA yield and quality in porcine tissues. Animals 13(4), 698.
Söderquist, A., Wallenbeck, A., Lindahl, C. 2023. Social support in a novel situation aimed for stunning and euthanasia of pigs may be increased by familiar pigs—A behavioural study with weaners. Animals 13(3), 481.

The common method of stunning pigs using high concentration carbon dioxide prior to slaughter poses an animal welfare issue, as the gas is aversive. Proof of concept for using nitrogen gas encapsulated in high-expansion foam...

Verspeek, J., Stevens, J. M. G. 2023. Behavioral and physiological response to inequity in bonobos (Pan paniscus). American Journal of Primatology 85(1), e23455.

Inequity aversion (IA), the affective, cognitive, and behavioral response to inequitable outcomes, allows individuals to avoid exploitation and therefore stabilizes cooperation. The presence of IA varies across animal species, which has stimulated research to investigate...

Luisi, B., Micheletta, J., Julle-Danière, E. et al. 2023. Monkeying around: Non-human primate behavioural responses to humans reproducing their facial expressions. Applied Animal Behaviour Science 265, 105990.

People are often observed mimicking animals’ facial expressions in an attempt to communicate with them. However, to date, there is limited understanding of how animals respond to humans reproducing their facial displays, or if this...

Clark, F. E. 2023. In the zone: Towards a comparative study of flow state in primates. Animal Behavior and Cognition 10(1), 62–88.

Flow is an altered state of feeling ‘in the zone’ when fully absorbed in a challenge and is associated with positive affective state (feelings). Despite almost five decades of research, Flow has not yet been...

Ferreira, M. F., Fàbrega, E., Pires, I. et al. 2023. Agonic aspiration of blood: Not useful as an animal-based indicator of electrical stunning ineffectiveness in pigs (Sus scrofa domesticus). Animals 13(14), 2292.

Agonic aspiration of blood (AAB) may result from an inadequate exsanguination with accidental trachea severing, that can be favoured by ineffective stunning of pigs (Sus scrofa domesticus). This study aimed to evaluate AAB as an...

Hognestad, B. W., Digranes, N., Opsund, V. G. et al. 2023. CO2 stunning in pigs: Physiological deviations at onset of excitatory behaviour. Animals 13(14), 2387.

Stunning by carbon dioxide (CO2) inhalation is controversial because it is associated with vigorous movements and behaviours which may or may not be conscious reactions. Furthermore, it is unknown whether some behaviours might indicate the...

Pretorius, Y., Eggeling, T., Ganswindt, A. 2023. Identifying potential measures of stress and disturbance during a captive to wild African elephant reintegration. PLOS ONE 18(10), e0291293.

There is increasing evidence of compromised welfare for elephants managed in captivity. Should such facilities eventually close, more elephants will need to be rehabilitated and reintegrated into the wild. The goal of such reintegration would...

Wiese, T. R., Rey Planellas, S., Betancor, M. et al. 2023. Qualitative Behavioural Assessment as a welfare indicator for farmed Atlantic salmon (Salmo salar) in response to a stressful challenge. Frontiers in Veterinary Science 10.

Animal welfare assessments have struggled to investigate the emotional states of animals while focusing solely on available empirical evidence. Qualitative Behavioural Assessment (QBA) may provide insights into an animal’s subjective experiences without compromising scientific rigor...

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...

Kieffer, J. D., Campler, M. R., Cheng, T.-Y. et al. 2022. Evaluation of a water-based medium-expansion foam depopulation method in suckling and finisher pigs. Animals 12(8), 1041.

The threat of foreign animal disease introduction through contaminated animal products, feed ingredients, and wildlife vectors have highlighted the need for additional approved methods for mass depopulation of swine under emergency scenarios, especially methods that...

Buckmaster, C. L., Levesque, D., LaFollette, M. et al. 2022. Five hot topics in refinement of nonhuman primate neuroscience research. Laboratory Animal Science Professional 10(1) (January/February), 24-26.

Members of the North American 3Rs Collaborative (NA3RsC) refinement initiative have chosen to summarize developments in five hot topics of interest: 1. Tips for welfare-friendly transport, chairing, and restraint; 2. Guidance on refining food and...

Hirata, S. 2022. Sky after 30 years: A brief biography of three biomedical research chimpanzees in Japan. Primates 63(2), 105–108.

This article describes the strategies employed by Kumamoto Sanctuary in Japan to integrate 3 retired chimpanzees – who each spent 30 years singly housed in a biomedical facility – with the sanctuary’s other residents.

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...

Bethell, E. J., Khan, W., Hussain, A. 2022. A deep transfer learning model for head pose estimation in rhesus macaques during cognitive tasks: Towards a nonrestraint noninvasive 3Rs approach. Applied Animal Behaviour Science 255, 105708.

Head orientation is a measure of attention used in behavioral psychological research with non-human primates. It is used across a broad range of disciplines and settings, from the field to the laboratory. Field methods are...

O'Malley, C. I., Hubley, R., Tambadou, H. et al. 2022. Refining restraint techniques for research pigs through habituation. Frontiers in Veterinary Science 9, 1016414.

Pigs are common research models and are strong animals that can be difficult to restrain. Improper restraint can put pigs and research personnel at risk for injury and induce stress, which can affect research outcomes...

Jacob, G., Katti, H., Cherian, T. et al. 2021. A naturalistic environment to study visual cognition in unrestrained monkeys. eLife 10, e63816.

Macaque monkeys are widely used to study vision. In the traditional approach, monkeys are brought into a lab to perform visual tasks while they are restrained to obtain stable eye tracking and neural recordings. Here...

Korenyi-Both, J., Vidaurre, J., Held, T. et al. 2022. Description of electroencephalographic data gathered using water-based medium-expansion foam as a depopulation method for nursery pigs. Scientific Reports 12(1), 16798.

The United States’ swine industry is under constant threat of foreign animal diseases, which may emerge without warning due to the globalized transportation networks moving people, animals, and products. Therefore, having disease control and elimination...

Fink, L. B., Mukobi, A., Gruber, L. et al. 2022. Longitudinal analysis of variability in fecal glucocorticoid metabolite concentrations in three orangutans (Pongo pygmaeus pygmaeus and Pongo pygmaeus abelii) before, during, and after transition from a regular habitat environment to temporary housing in indoor holding facilities. Animals 12(23), 3303.

Considerable research has been conducted on the effects of inter-institutional transfers, but far less consideration has been given to intra-institutional transfers and extended housing in off-habitat holding. On 15 May 2018, The Oregon Zoo’s orangutans...

Korenyi-Both, J., Vidaurre, J., Held, T. et al. 2022. Description of electroencephalographic data gathered using water-based medium-expansion foam as a depopulation method for nursery pigs. Scientific Reports 12(1), 16798.

The United States’ swine industry is under constant threat of foreign animal diseases, which may emerge without warning due to the globalized transportation networks moving people, animals, and products. Therefore, having disease control and elimination...

Laméris, D. W., Verspeek, J., Salas, M. et al. 2022. Evaluating self-directed behaviours and their association with emotional arousal across two cognitive tasks in bonobos (Pan paniscus). Animals 12(21), 3002.

Self-directed behaviours (SDBs) are widely used as markers of emotional arousal in primates, and are commonly linked to negative arousal, or are used as indicators of stress or poor welfare. However, recent studies suggest that...

Martin, J. E., Baxter, E. M., Clarkson, J. M. et al. 2022. Characterizing candidate decompression rates for hypobaric hypoxic stunning of pigs. Part 1: Reflexive behavior and physiological responses. Frontiers in Veterinary Science 9, 1027878.

Alternatives to carbon dioxide (CO2) stunning for the commercial slaughter of pigs are urgently needed because there is robust evidence that exposing pigs to hypercapnic environments is associated with pain, fear, and distress. Hypobaric hypoxia...

Mason, G. J., Lavery, J. M. 2022. What is it like to be a bass? Red herrings, fish pain and the study of animal sentience. Frontiers in Veterinary Science 9, 788289.

Debates around fishes’ ability to feel pain concern sentience: do reactions to tissue damage indicate evaluative consciousness (conscious affect), or mere nociception? Thanks to Braithwaite’s research leadership, and concerns that current practices could compromise welfare...

O’Malley, C. I., Hubley, R., Tambadou, H. et al. 2022. Refining restraint techniques for research pigs through habituation. Frontiers in Veterinary Science 9, 1016414.

Pigs are common research models and are strong animals that can be difficult to restrain. Improper restraint can put pigs and research personnel at risk for injury and induce stress, which can affect research outcomes...