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. 
Silva-Reis, R., Faustino-Rocha, A. I., Silva, J. et al. 2023. Studying and analyzing humane endpoints in the fructose-fed and streptozotocin-injected rat model of diabetes. Animals 13(8), 1397.

This work aimed to define a humane endpoint scoring system able to objectively identify signs of animal suffering in a rat model of type 2 diabetes. Sprague-Dawley male rats were divided into control and induced...

Warwick, C., Pilny, A., Steedman, C. et al. 2023. Mobile zoos and other itinerant animal handling events: Current status and recommendations for future policies. Animals 13(2), 214.

Mobile zoos are events in which non-domesticated (exotic) and domesticated species are transported to venues such as schools, hospitals, parties, and community centres, for the purposes of education, entertainment, or social and therapeutic assistance. We...

Whitham, J. C., Hall, K., Lauderdale, L. K. et al. 2023. Integrating reference intervals into chimpanzee welfare research. Animals 13(4), 639.

Animal welfare researchers are committed to developing novel approaches to enhance the quality of life of chimpanzees living in professional care. To systematically monitor physical, mental, and emotional states, welfare scientists highlight the importance of...

Williams, E., Hunton, V., Hosey, G. et al. 2023. The impact of visitors on non-primate species in zoos: A quantitative review. Animals 13(7), 1178.

Visitors are a prominent feature in the lives of zoo animals, and their presence can cause a range of impacts on zoo animals (typically classed as positive, negative or neutral impacts), commonly referred to as...

Zieliński, D. 2023. The effect of enrichment on leopard geckos (Eublepharis macularius) housed in two different maintenace systems (rack system vs. Terrarium). Animals 13(6), 1111.

The aim of this study was to test the usefulness of environmental enrichment for Eublepharis macularius depending on the maintenance method (terrarium vs. rack system). The hypothesis was that reptiles kept in an extremely low-stimulus...

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...

Lupfer, G., Brandenburger, A., Machado, M. et al. 2023. Ultrasonic vocalizations near 30 kHz may indicate excitement rather than distress in female Wistar rats. Applied Animal Behaviour Science 261, 105881.

Rats emit ultrasonic vocalizations (USVs), sometimes referred to as 50-kHz vocalizations, during activities such as play and lower-frequency USVs, sometimes referred to as 22-kHz vocalizations, when experiencing distress. Definitions of 22-kHz vocalizations vary in terms...

Rooney, N. J., Baker, P. E., Blackwell, E.-J. et al. 2023. Run access, hutch size and time-of-day affect welfare-relevant behaviour and faecal corticosterone in pair-housed pet rabbits. Applied Animal Behaviour Science 262, 105919.

Although there exist several studies examining the housing needs of rabbits kept in laboratories and for meat, studies of the requirements of pet rabbits are few and focus entirely on single rabbits. Pet rabbits are...

Edes, A. N., Brown, J. L., Edwards, K. L. 2023. Evaluating individual biomarkers for predicting health risks in zoo-housed chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). American Journal of Primatology 85(3), e23457.

Although biomarkers are often used for predicting morbidity and mortality in humans, similar data are lacking in our closest relatives. This study analyzed 16 biomarkers in zoo-housed chimpanzees and bonobos from serum samples collected during...

Danforth, M. D., Clyde, V. L., Jourdan, B. et al. 2023. Blood pressure monitoring in zoologically managed bonobos (Pan paniscus). American Journal of Primatology 85(3), e23474.

In response to the growing evidence that hypertension may play a significant role in the development of cardiovascular disease (CVD) in bonobos, the Great Ape Heart Project established a finger blood pressure (BP) monitoring protocol...

Tédonzong, L. R. D., Ndju'u, M. B. M., Tchamba, M. et al. 2023. The influence of vegetation structure on sleeping site selection by chimpanzees (Pan troglodytes troglodytes). American Journal of Primatology 85(7), e23505.

Sleep is an important aspect of great ape life; these animals build sleeping platforms every night. In a community of chimpanzees, each subgroup selects a sleeping site where each individual builds a sleeping platform, mostly...

O’Brien, S. L., Cronin, K. A. 2023. Doing better for understudied species: Evaluation and improvement of a species-general animal welfare assessment tool for zoos. Applied Animal Behaviour Science 264, 105965.

Accredited zoos and aquariums are required to have a welfare assessment process in place for the animals in their care. However, welfare assessment theoretical frameworks and methodologies vary widely. Previous studies have shown that taxonomic...

Broadfoot, C. K., Lenell, C., Kelm-Nelson, C. A. et al. 2023. Effects of social isolation on 50-kHz ultrasonic vocalizations, affective state, cognition, and neurotransmitter concentrations in the ventral tegmental and locus coeruleus of adult rats. Behavioural Brain Research 437, 114157.

Vocal communication, cognition, and affective state are key features of sustained health and wellness, and because vocalizations are often socially-motivated, social experience likely plays a role in these behaviors. The monoaminergic systems of the ventral...

Lobina, C., Maccioni, P., Gessa, G. L. et al. 2023. Exposure to an enriched environment exerts anxiolytic effects in Sardinian alcohol-preferring rats. Behavioural Brain Research 452, 114557.

Exposure to an enriched environment (EE) has been reported to generate multiple beneficial effects in rodents, including – among the many – amelioration of anxiety-related behaviors. The present study investigated whether living in an EE...

Núñez-Murrieta, M. A., Coria-Avila, G. A., Martínez, A. J. et al. 2023. Preterm rat survival is enhanced by gestational environmental enrichment. Behavioural Processes 205, 104820.

Throughout the last decade, the estimated global human preterm birth rate was 10.6 %, with higher rates in Asia, South America, and Africa. Preterm individuals, even in adulthood, are more likely to develop cardiorespiratory, renal...

Stark, R. A., Brinkman, B., Gibb, R. L. et al. 2023. Atypical play experiences in the juvenile period has an impact on the development of the medial prefrontal cortex in both male and female rats. Behavioural Brain Research 439, 114222.

In rats reared without play, or with limited access to play during the juvenile period, the dendrites of pyramidal neurons of the medial prefrontal cortex (mPFC) exhibit more branching than rats reared with more typical...

Becker, L., Mallien, A. S., Pfeiffer, N. et al. 2023. Evidence-based severity assessment of the forced swim test in the rat. PLOS ONE 18(10), e0292816.

The forced swim test (FST) is a traditional assay, which has been used for more than 40 years to assess antidepressant effects of novel drug candidates. In recent years, a debate about the test has...

Bogdan, R., Kayumova, R., Schwarting, R. K. W. et al. 2023. Wildtype peers rescue social play and 50-kHz ultrasonic vocalization deficits in juvenile female Cacna1c heterozygous rats. Frontiers in Behavioral Neuroscience 17.

Healthy brain development depends on early social practices and experiences. The risk gene CACNA1C is implicated in numerous neuropsychiatric disorders, in which key characteristics include deficits in social functioning and communication. Recently, we reported sex-dependent...

Bradley, H. S., Craig, M. D., Tomlinson, S. et al. 2023. Ecological considerations when designing mitigation translocations: An Australian reptile case study. Animals 13(16), 2594.

Translocation science has made considerable progress over the last two decades; however, reptile translocations still frequently fail around the world. Major knowledge gaps surround the basic ecology of reptile species, including basic factors such as...

Brando, S., Norman, M. 2023. Handling and training of wild animals: Evidence and ethics-based approaches and best practices in the modern zoo. Animals 13(14), 2247.

There is an ethical responsibility to provide all animals living in human care with optimal and positive well-being. As animals living in zoos and aquariums frequently interact with their human caregivers as part of their...

Campbell-Ward, M. 2023. Quality-of-life assessments in zoo animals: Not just for the aged and charismatic. Animals 13(21), 3394

Zoos should aim to provide all of their animals with a good quality of life (QoL) throughout all life stages. In parallel with the evolution of QoL assessment questionnaires and tools in human and domestic...

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...

Domínguez-Oliva, A., Hernández-Ávalos, I., Olmos-Hernández, A. et al. 2023. Thermal response of laboratory rats (Rattus norvegicus) during the application of six methods of euthanasia assessed by infrared thermography. Animals 13(18), 2820.

Refinement is one of the principles aiming to promote welfare in research animals. The techniques used during an experimental protocol, including euthanasia selection, must prevent and minimize suffering. Although the current euthanasia methods applied to...

Domínguez-Oliva, A., Olmos-Hernández, A., Hernández-Ávalos, I. et al. 2023. Rat grimace scale as a method to evaluate animal welfare, nociception, and quality of the euthanasia method of wistar rats. Animals 13(20), 3161.

Refinement of experimental procedures in animal research has the objective of preventing and minimizing pain/distress in animals, including the euthanasia period. This study aimed to evaluate pain associated with six methods of euthanasia in Wistar...

Du Plooy, K. J., Swan, G. E., Myburgh, J. G. et al. 2023. Electroencephalogram (EEG) assessment of brain activity before and after electrical stunning in the Nile crocodile (Crocodylus niloticus). Scientific Reports 13(1), 20250.

Electrical stunning is used to capture crocodiles to perform routine management procedures. It is essential from a welfare point that electrical stunning must cause unconsciousness in animals. However, there is no information of whether or...