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. 
Edwards, K. L., Miller, M. A., Carlstead, K. et al. 2019. Relationships between housing and management factors and clinical health events in elephants in North American zoos. PLOS ONE 14(6), e0217774.

Elephants experience a number of health issues that can contribute to their well-being and survival. In managed populations, housing conditions and management practices can influence individual health, so potential risk factors associated with morbidity or...

Brown, J. L., Carlstead, K., Bray, J. D. et al. 2019. Individual and environmental risk factors associated with fecal glucocorticoid metabolite concentrations in zoo-housed Asian and African elephants. PLOS ONE 14(9), e0217326.

A recent large-scale welfare study in North America involving 106 Asian (Elephas maximus) and 131 African (Loxodonta africana) elephants at 64 accredited facilities identified links (i.e., risk factors) between zoo environmental factors and a number...

Crawley, J. A. H., Lahdenperä, M., Seltmann, M. W. et al. 2019. Investigating changes within the handling system of the largest semi-captive population of Asian elephants. PLOS ONE 14(1), e0209701.

The current extinction crisis leaves us increasingly reliant on captive populations to maintain vulnerable species. Approximately one third of Asian elephants (Elephas maximus) are living in semi-captive conditions in range countries. Their relationship with humans...

Scott, N. L., LaDue, C. A. 2019. The behavioral effects of exhibit size versus complexity in African elephants: A potential solution for smaller spaces. Zoo Biology 38(5), 448-457.

Population-level analyses suggest that habitat complexity, but not necessarily space availability, has important welfare outcomes for elephants in human care. At the Dallas Zoo, the opening of a new exhibit complex allowed us to measure...

Cox, R. J., Nol, P., Ellis, C. K. et al. 2019. Research with agricultural animals and wildlife. ILAR Journal 60(1), 66-73.

In fiscal year 2016, agricultural animals such as swine, sheep, goats, and cattle represented 10% of the 820 812 animals used in USDA-regulated research. In addition to traditional agricultural animals, research studies using captive wildlife...

Colby, L. A., Nowland, M. H., Kennedy, L. H. 2019. Clinical Laboratory Animal Medicine: An Introduction (5th ed). Wiley-Blackwell, Ames, IA.

The revised fifth edition of Clinical Laboratory Animal Medicine: An Introduction is an accessible guide to basic information for conducting animal research safely and responsibly. It includes a review of the unique anatomic and physiologic...

Schiffmann, C., Clauss, M. 2019. Impact of a new exhibit on stereotypic behavior in an elderly captive African elephant. Journal of Zoo and Aquarium Research 7(1), 37-43.

Stereotypic behavior in zoo elephants is considered an indicator of impaired welfare. The underlying causes are diverse and many aspects are still unexplored. Nevertheless, many zoological institutions take huge efforts to improve the well-being of...

Fischer, C. P., Romero, L. M. 2019. Chronic captivity stress in wild animals is highly species-specific. Conservation Physiology 7(1), coz093.

Wild animals are brought into captivity for many reasons—conservation, research, agriculture and the exotic pet trade. While the physical needs of animals are met in captivity, the conditions of confinement and exposure to humans can...

Williams, E., Chadwick, C. L., Yon, L. et al. 2018. A review of current indicators of welfare in captive elephants (Loxodonta africana and Elephas maximus). Animal Welfare 27(3), 235-249.

Concerns over elephant welfare in UK zoos have implications for their future in captivity. To monitor improvements made to elephant welfare in UK zoos, non-invasive, valid and reliable indicators of welfare are needed. Using a...

Hacker, C. E., Miller, L. J., Schulte, B. A. 2018. Examination of enrichment using space and food for African elephants (Loxodonta africana) at the San Diego Zoo Safari Park. Animal Welfare 27(1), 55-65.

Concern for elephant welfare in zoological facilities has prompted a number of exhibit and management modifications, including those involving enrichment. Knowledge of how these changes impact indicators of welfare, such as elephant movement and behaviour...

Bacon, H. 2018. Behaviour-based husbandry—A holistic approach to the management of abnormal repetitive behaviors. Animals 8(7), 103.

The field of zoo animal welfare science has developed significantly over recent years. However despite this progress in terms of scientific research, globally, zoo animals still face many welfare challenges. Recently, animal welfare frameworks such...

Clegg, I. 2018. Cognitive bias in zoo animals: An optimistic outlook for welfare assessment. Animals 8(7), 104.

Cognitive bias testing measures how emotional states can affect cognitive processes, often described using the “glass half-full/half-empty” paradigm. Classical or operant conditioning is used to measure responses to ambiguous cues, and it has been reported...

Wolfensohn, S., Shotton, J., Bowley, H. et al. 2018. Assessment of welfare in zoo animals: Towards optimum quality of life. Animals 8(7), 110.

Zoos are required to maintain a high standard of animal welfare, and this can be assessed using a combination of resource-based and animal-based indices usually divided into behavioural indicators, physiological indicators and clinical/pathological signs. Modern...

Chotard, H., Ioannou, S., Davila-Ross, M. 2018. Infrared thermal imaging: Positive and negative emotions modify the skin temperatures of monkey and ape faces. American Journal of Primatology 80(5), e22863.

Facial thermography has enabled researchers to noninvasively and continuously measure the changes of a range of emotional states in humans. The present work used this novel technology to study the effect of positive and negative...

Schiffmann, C., Hoby, S., Wenker, C. et al. 2018. When elephants fall asleep: A literature review on elephant rest with case studies on elephant falling bouts, andpractical solutions for zoo elephants. Zoo Biology 37(3), 133–145.

Little attention has been paid to the resting and sleeping behavior of zoo elephants so far. An important concern is when elephants avoid lying down, due to degenerative joint and foot disease, social structure, or...

Coke, C., Skoumbourdis, E., Rodgers, J. C. et al. 2018. Blunting/cutting canines of adult male monkeys: A discussion by the Laboratory Animal Refinement & Enrichment Forum. Animal Technology & Welfare 17(2), 105-107.

"When you keep adult Rhesus macaque (Macaca mulatta) males, adult Cynomolgus (Macaca fascicularis) males or adult Vervet males (Chlorocebus pygerythrus), in the same enclosure, is it advisable to have the canines of the males blunted...

Lutz, C. K. 2018. A cross-species comparison of abnormal behavior in three species of singly-housed old world monkeys. Applied Animal Behaviour Science 199, 52-58.

Abnormal behavior occurs in a number of captive nonhuman primate species and is often used as an indicator of welfare. However, reported levels of abnormal behavior often vary across species, making general welfare judgments difficult...

Perdue, B. M., Beran, M. J., Washburn, D. A. 2018. A computerized testing system for primates: Cognition, welfare, and the Rumbaughx. Behavioural Processes 156, 37-50.

Innovations in apparatus technology come about for a variety of reasons such as the need to use the same methodology with various species, the opportunity to present dynamic and carefully controlled stimuli, the goal of...

Heyworth, C., Olivo, D. 2018. Environmental and psychological enrichment for NHPs reimagined and repurposed. Laboratory Animal Science Professional 5(4) (December), 39-43.

This article describes creative enrichment ideas for nonhuman primates, including celery stalks embedded with seeds; paper rolled into tubes, braided and filled with fruit and seeds; pineapple crowns loaded with treats; dry spaghetti noodles coated...

Unakafov, A. M., Möller, S., Kagan, I. et al. 2018. Using imaging photoplethysmography for heart rate estimation in non-human primates. PLOS ONE 13(8), e0202581.

For humans and for non-human primates heart rate is a reliable indicator of an individual’s current physiological state, with applications ranging from health checks to experimental studies of cognitive and emotional state. In humans, changes...

French, F., Mancini, C., Sharp, H. 2018. High tech cognitive and acoustic enrichment for captive elephants. Journal of Neuroscience Methods 300, 173-183.

This paper investigates the potential for using technology to support the development of sensory and cognitive enrichment activities for captive elephants. It explores the usefulness of applying conceptual frameworks from interaction design and game design...

Morfeld, K. A., Brown, J.L. 2017. Metabolic health assessment of zoo elephants: Management factors predicting leptin levels and the glucose-to-insulin ratio and their associations with health parameters. PLOS ONE 12(11), e0188701.

Screening for metabolic-related health problems can enhance animal welfare, so the purpose of this study was to conduct the first metabolic health assessment of zoo elephants and use epidemiological methods to determine how factors in...

Chadwick, C. L., Williams, E., Asher, L. et al. 2017. Incorporating stakeholder perspectives into the assessment and provision of captive elephant welfare. Animal Welfare 26(4), 461-472.

Recent concerns over the welfare of elephants in UK zoos have implications for their future in captivity, and it is clear that improvements in welfare should be made. Evidence suggests that the knowledge of experienced...

Krebs, B. L., Torres, E., Chesney, C. et al. 2017. Applying behavioral conditioning to identify anticipatory behaviors. Journal of Applied Animal Welfare Science 20(2), 155-175.

The ability to predict regular events can be adaptive for nonhuman animals living in an otherwise unpredictable environment. Animals may exhibit behavioral changes preceding a predictable event; such changes reflect anticipatory behavior. Anticipatory behavior is...

Martin, A. L. 2017. Theprimatologist as a behavioral engineer. American Journal of Primatology 79, e22500.

The field of primate behavior management has had only limited success in preventing and treating abnormal behaviors, such as stereotypy and self‐injury, in captive non‐human primates (NHP). In contrast, applied behavior analysts have had great...