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. 
Kroeker, R., Chichester, L., Lee, G. H. et al. 2019. Effects of pregnancy, outdoor access, and antifungal medication on hair loss in breeding-age female pigtailed macaques (Macaca nemestrina). Comparative Medicine 69(3), 221–227.

Over 18 mo, adult female pigtailed macaques (Macaca nemestrina) housed at a breeding facility in Arizona were monitored every 6 mo for alopecia. The study period coincided with the movement of a majority of animals...

National Academies of Sciences, Engineering, and Medicine. 2019. Care, Use, and Welfare of Marmosets as Animal Models for Gene Editing-Based Biomedical Research: Proceedings of a Workshop. The National Academies Press: Washington, DC, 122 pp.

The marmoset, a type of small monkey native to South America, is a research model of increasing importance for biomedical research in the United States and globally. Marmosets offer a range of advantages as animal...

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...

Bell, E., Price, E., Balthes, S. et al. 2019. Flight patterns in zoo-housed fruit bats (Pteropus spp.). Zoo Biology 38(3), 248-257.

Maintaining the capacity for sustained flight in captivity is a key goal for the management of threatened fruit bats. We developed quantifiable descriptions of flight complexity and used them to assess the suitability of an...

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...

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...

Lutz, C. K., Brown, T. A. 2018. Porches as enrichment for singly housed cynomolgus macaques (Macaca fascicularis). JAALAS 57(2), 138-142.

Effective environmental enrichment is used by animals, promotes species-typical behavior, and decreases abnormal behavior. Porches attached to the front of an animal's cage provide additional space, perching opportunities, and a better view of the surroundings...

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...

Brown, T. A., Lutz, C. K., 2018. An assessment of porches as enrichment for singly housed cynomolgus macaques (Macaca fascicularis). American Journal of Primatology 80(S1), 18 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #21).

Effective environmental enrichment encourages usage, promotes species‐typical behaviors, and/or decreases abnormal behaviors. Porches are small cages that attach to the primary cage of an animal to provide additional space and a better view of the...

Woelffer, S., Ace, L., Sullivan, J. et al., 2018. Enhanced physical environment in single-housed macaques: A long-term usage profile of cage extensions. American Journal of Primatology 80(S1), 19-20 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #25).

Social housing is always preferred in the research environment; however, single housing is sometimes necessitated by scientific objectives or social incompatibility. In these cases, other environmental enhancements are developed to provide indirect social interactions. We...

Yoshimoto, T., Takahashi, E., Yamashita, S. et al. 2018. Larger cages with housing unit environment enrichment improve the welfare of marmosets. Experimental Animals 67(1), 31-39.

The provision of adequate space for laboratory animals is essential not only for good welfare but accurate studies. For example, housing conditions for primates used in biomedical research may negatively affect welfare and thus the...

Koistinen, T., Raatikainen, S., Sepponen, J. et al. 2018. Resting preferences and welfare of Finnraccoon (Nyctereutes procyonoides ussuriensis) females housed in various housing conditions in winter. Applied Animal Behaviour Science 207, 129-137.

Raccoon dog (Nyctereutes procyonoides ussuriensis) is the only canid species using facultative passive wintering strategy. The aim of the present study is to document the behaviour and welfare of the farmed variant of the species...

Tennant, K. S., Segura, V. D., Morris, M. C. et al. 2018. Achieving optimal welfare for the Nile hippopotamus (Hippopotamus amphibius) in North American zoos and aquariums. Behavioural Processes 156, 51-57.

Compared to other megafauna managed in zoos and aquariums, the current state of welfare for the Nile hippopotamus (Hippopotamus amphibius) is poorly understood. Complex behavior and physiological characteristics make hippos a difficult species to manage...

Freling, S. 2018. Learning about tree shrews. Laboratory Animal Science Professional 5(4) (December), 14-17.

This article describes the natural behaviors of tree shrews and how to accommodate for their care and welfare in a laboratory, including information on infant rearing and diet, caging, environmental enrichment, and mitigation of stressors.

Ferrecchia, C., Pincolini, K., Chum, H. et al. 2017. Husbandry of laboratory-housed Egyptian (Rousettus aegyptiacus) fruit bats. Laboratory Animal Science Professional 5(2) (June), 18-23.

The University of California, Berkeley, houses a variety of unique species, each requiring their own specific husbandry protocols, as well as additional enrichment and safety protocols. While housing of bats in zoological parks is common...

Skrinyer, A. J., Faure, P. A., Dannemiller, S. et al. 2017. Care and husbandry of the world’s only flying mammals. Laboratory Animal Science Professional 5(2) (June), 24-27.

Husbandry of these unusual and complicated creatures requires creativity and attention to species-specific needs. Authors from the Northeast Ohio Medical University (NEOMED), SUNY Downstate, and McMaster University formed a collaboration aimed at optimizing the health...

Cavallaro, J., Stevens Jr., R. W., Wilson, B. et al. 2017. Social housing pig tail macaques in repurposed chimpanzee enclosures. Laboratory Animal Science Professional 5(2) (June), 60-61.

As chimpanzees are retired from research, enclosures such as the Primadomes™ become available for repurposing for other monkey species. However, modifications are necessary to meet specific monkey species needs, and considerations for animal handling and...

Razal, C., Bryant, J., Miller, L. 2017. Monitoring the behavioral and adrenal activity of giraffe (Giraffa camelopardalis) to assess welfare during seasonal housing changes. Animal Behavior and Cognition 4(2), 154–164.

In inclement weather, northern zoos are required to provide animals from warmer climates with indoor exhibits. These indoor exhibits are typically smaller, lack natural substrate, and have lower levels of stimulation for the animals. The...

Holdgate, M. R., Meehan, C. L., Hogan, J. N. et al. 2016. Walking behavior of zoo elephants: Associations between GPS-measured daily walking distances and environmental factors, social factors, and welfare indicators. PLOS ONE 11(7), e0150331.

Research with humans and other animals suggests that walking benefits physical health. Perhaps because these links have been demonstrated in other species, it has been suggested that walking is important to elephant welfare, and that...

Holdgate, M. R., Meehan, C. L., Hogan, J. N. et al. 2016. Recumbence behavior in zoo elephants: Determination of patterns and frequency of recumbent rest and associated environmental and social factors. PLOS ONE 11(7), e0153301.

Resting behaviors are an essential component of animal welfare but have received little attention in zoological research. African savanna elephant (Loxodonta africana) and Asian elephant (Elephas maximus) rest includes recumbent postures, but no large-scale investigation...

Miller, M. A., Hogan, J. N., Meehan, C. L. 2016. Housing and demographic risk factors impacting foot and musculoskeletal health in African elephants [Loxodonta africana] and Asian elephants [Elephas maximus] in North American zoos. PLOS ONE 11(7), e0155223.

For more than three decades, foot and musculoskeletal conditions have been documented among both Asian [Elephas maximus] and African [Loxodonta africana] elephants in zoos. Although environmental factors have been hypothesized to play a contributing role...

Powell, D. M., Vitale, C. 2016. Behavioral changes in female Asian elephants when given access to an outdoor yard overnight. Zoo Biology 35(4), 298-303.

A study was conducted at the Bronx Zoo to determine whether providing elephants with access to an outdoor corral at night had any significant effects on behavior, use of space, and use of a sand...

O'Keefe, S. 2016. Non-human primate housing facility at Newcastle University. Animal Technology and Welfare 15(2), 131-132.

Monkeys first arrived in the Comparative Biology Centre (CBC) at Newcastle University in 2000. They were housed in three small separate units consisting of steel and wooden cages. In 2011 a decision was made to...