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. 
Robinson, L. M., Weiss, A. (Eds.) 2023. Nonhuman Primate Welfare: From History, Science, and Ethics to Practice. Springer, Cham, Switzerland. 671 p.

This volume reviews the broad topic of welfare in nonhuman primates under human care. Chapters detail the history of primates in captivity, ethical and legal issues surrounding the use of nonhuman primates as entertainment or...

Ausderau, K. K., Colman, R. J., Kabakov, S. et al. 2023. Evaluating depression- and anxiety-like behaviors in non-human primates. Frontiers in Behavioral Neuroscience 16, 1006065.

Depression and anxiety are some of the most prevalent and debilitating mental health conditions in humans. They can present on their own or as co-morbidities with other disorders. Like humans, non-human primates (NHPs) can develop...

Brando, S., Vitale, A., Bacon, M. 2023. Promoting good nonhuman primate welfare outside regular working hours. Animals 13(8), 1423.

Promoting good primate welfare outside of daylight hours is an important task. The responsibility to provide a complex environment and environmental enrichment is an essential element of primate wellbeing programs that should be approached from...

Neal Webb, S., Schapiro, S. 2023. Locomotion as a measure of well-being in captive chimpanzees (Pan troglodytes). Animals 13(5), 803.

Locomotion in non-human primates, including walking, climbing, and brachiating among other types of movement (but not pacing), is a species-typical behavior that varies with age, social housing conditions, and environmental factors (e.g., season, food availability...

Pallieres, C. G. D., Rose, P. E. 2023. Two’s company, three species is a crowd? A webcam-based study of the behavioural effects of mixed-species groupings in the wild and in the zoo. PLOS ONE 18(4), e0284221.

Mixed species exhibits in zoos are used to create larger, more stimulating environments to support naturalistic interactions between species. In the wild, mixed species groups are observed as having lower rates of vigilance, presumably due...

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...

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...

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...

Beekmans, M. H. C., Vinke, C. M., Maijer, A. et al. 2023. Increasing foraging times with appetitive and consummatory foraging enrichment in grey parrots (Psittacus erithacus). Applied Animal Behaviour Science 265, 105986.

Foraging enrichment is considered one of the most effective ways to enhance expression of species-typical behaviours and prevent the development of abnormal (repetitive) behaviours in captive animals. However, foraging enrichments for parrots have thus far...

Bertin, A., Mulot, B., Nowak, R. et al. 2023. Captive blue-and-yellow macaws (Ara ararauna) show facial indicators of positive affect when reunited with their caregiver. Behavioural Processes 206, 104833.

In mammals, human-animal bonding is recognized as a source of positive affect for companion or farm animals. Because this remains unexplored in birds, we investigated captive parrots’ perspective of the human-animal relationship. We used a...

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...

Fultz, A., Lewis, R., Kelly, L. et al. 2023. Behavioral welfare research for the management of sanctuary chimpanzees (pan troglodytes). Animals 13(16), 2595.

Chimp Haven is a sanctuary for chimpanzees retired from biomedical research, rescued from the pet trade, or re-homed after other organizations could no longer care for them. To provide optimal care for over 300 chimpanzees...

Kim, S., Kim, N., Kim, H. et al. 2023. Various endoscopic approaches for removal of proventricular foreign bodies in parrots—Three case reports. Animals 13(24), 3839.

Although the use of incision-free endoscopy for foreign body (FB) removal in dogs and cats has been extensively documented, its application in birds remains limited. Thus, we present the endoscopic removal of gastrointestinal (GI) FBs...

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...

Turcu, M.-C., Paștiu, A. I., Bel, L.-V. et al. 2023. Minimally invasive sampling methods for molecular sexing of wild and companion birds. Animals 13(21), 3417.

Birds are highly social and must be paired in order to increase their welfare. Most bird species are monomorphic; therefore, molecular sexing helps provide appropriate welfare for birds. Moreover, early sex determination can be of...

van Zeeland, Y. R. A., Schoemaker, N. J., Lumeij, J. T. 2023. Contrafreeloading indicating the behavioural need to forage in healthy and feather damaging Grey parrots. Animals 13(16), 2635.

Contrafreeloading (CFL) is a concept that describes the preference of an animal to work for food even when identical food is freely available, and reflects an intrinsic motivation to engage in foraging-related activities. However, altered...

Cordoni, G., Ciarcelluti, G., Pasqualotto, A. et al. 2023. Is it for real? Structural differences between play and real fighting in adult chimpanzees (Pan troglodytes). American Journal of Primatology 85(9), e23537.

In primates, as well as in other mammals, play fighting (PF) is a complex form of playful activity that is structurally similar to real fighting (RF) and may also be used in a competitive way...

Mahdavi, I., Abdi-Hachesoo, B., Ansari-Lari, M. et al. 2023. Prevalence and risk factors of feather damaging behavior in companion parrots: A cross-sectional study in Iran. Applied Animal Behaviour Science 266, 106028.

A cross-sectional study was conducted to estimate the prevalence of feather damaging behavior (FDB) and evaluate the related risk factors among companion psittacine birds in Iran. For data collection, a structured questionnaire was prepared and...

Quintanilla, B., Diana, A., Salas, M. 2023. Enhancing welfare in a mixed exhibit: The impact of dispersed whole food on activity levels and feeding behaviours of Mexican military macaws and red-billed curassows. Journal of Zoo and Aquarium Research 11(4), 366–375.

Presenting chopped food in a bowl is a traditional feeding technique in zoos worldwide. However, it may not provide sufficient stimulation for many species to satisfy their behavioural needs. Recent studies suggest that dispersing food...

Rosati, A. G., Sabbi, K. H., Bryer, M. A. H. et al. 2023. Observational approaches to chimpanzee behavior in an African sanctuary: Implications for research, welfare, and capacity-building. American Journal of Primatology 85(9), e23534.

Research in African ape sanctuaries has emerged as an important context for our understanding of comparative cognition and behavior. While much of this work has focused on experimental studies of cognition, these animals semi-free-range in...

Schreier, A. L., Readyhough, T. S., Moresco, A. et al. 2023. Social dynamics of a newly integrated bachelor group of Asian elephants (Elephas maximus): Welfare implications. Journal of Applied Animal Welfare Science 26(2), 229–246.

Male associations are a typical component of elephant society, allowing bulls to practice appropriate social behavior. To improve zoo elephant welfare, it is important to provide bulls with social opportunities. In fall 2018, Denver Zoo...

Tsuchiya, Y., Yayota, M., Kashima, Y. et al. 2023. Nutritional effect of feeding enrichment using bamboo Pleioblastus spp. in zoo-kept Asian elephants Elephas maximus. Journal of Zoo and Aquarium Research 11(2), 267–273.

Many zoos use browse and other roughage as feed ingredients and enrichment tools for elephants. Amongst these are bamboo species (e.g. Pleioblastus spp.), which belong to the family of grasses. Bamboo is used in zoos...