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. 
Eagan, T. 2019. Evaluation of enrichment for reptiles in zoos. Journal of Applied Animal Welfare Science 22(1), 69-77.

Studies on environmental enrichment for reptiles are lacking in the scientific literature. Although the literature reflects a limited take on reptile enrichment in the zoological community, it may not be the case in reality as...

Frediani, M. H., Pizzutto, C. S., Alves, M. B. R. et al. 2019. Effect of simple and low-cost enrichment items on behavioral, clinical, and productive variables of caged laying hens. Journal of Applied Animal Welfare Science 22(2), 139-148.

Housing layers in battery cages is a practice still used by many countries but it has been criticized because of its influence on behavioral repertoire of birds. We investigated whether simple and affordable enrichment devices...

Vasdal, G., Vas, J., Newberry, R. C. et al. 2019. Effects of environmental enrichment on activity and lameness in commercial broiler production. Journal of Applied Animal Welfare Science 22(2), 197-205.

The aim of this pilot study was to investigate the effects of commercially applied environmental enrichments on behavior and lameness in broilers. Two consecutive flocks of broilers were observed at 16 days and 30 days...

Mastellone, V., Bovera, F., Musco, N. et al. 2019. Mirrors improve rabbit natural behavior in a free-range breeding system. Animals 9(8), 533.

The aim of this research was to evaluate the possible usefulness of mirrors in improving rabbit behavior in a free-range breeding system. Three groups (each consisting of nine replicates of three animals) were compared: isolated...

Trocino, A., Zomeño, C., Filiou, E. et al. 2019. The use of environmental enrichments affects performance and behavior of growing rabbits housed in collective pens. Animals 9(8), 537.

This study assessed the effects of an elevated plastic-slatted platform and/or a plastic hiding tube in collective pens with large group sizes (27 or 36 rabbits/pen; 16 rabbits/m2) on the performance and welfare of rabbits...

Bach, M. H., Tahamtani, F. M., Pedersen, I. J. et al. 2019. Effects of environmental complexity on behaviour in fast-growing broiler chickens. Applied Animal Behaviour Science 219, 104840.

Modern broiler chickens spend a great proportion of their time resting, which poses a major threat to their welfare due to the increased risk of contact dermatitis and the incidence and severity of leg problems...

Shi, H., Li, B., Tong, Q. et al. 2019. Influence of nest boxes and claw abrasive devices on feather pecking and the fear responses of layer breeders in natural mating colony cages. Applied Animal Behaviour Science 220, 104842.

Natural mating colony cages for parent-stock layer breeders, instead of conventional cages with artificial insemination, have been widely adopted by many commercial farms in China. Although some natural mating behaviours can be expressed and broader...

Harris, K., New, R., Smith, P. et al. 2019. Refinement: promoting Gallus Gallus welfare in an experimental poultry unit. Animal Technology and Welfare 18(2), 137-139. (IAT Congress 2018 Poster Presentation)

The poultry team at The Pirbright Institute reviewed existing husbandry practices and trialled several refinement practices. The objective was to provide the birds used in research with an environment which enables them to express their...

Estrada, C., Cuenca, L., Cano-Fernandez, L. et al. 2019. Voluntary exercise reduces plasma cortisol levels and improves transitory memory impairment in young and aged Octodon degus. Behavioural Brain Research 373, 112066.

Sleep deprivation (SD) has been reported to induce transient cognitive impairment in functional domains commonly affected in dementia, including memory. Indeed, sleep disturbance has been proposed as an early marker for Alzheimer’s disease (AD). SD...

Baker, S. W., Tucci, E. R., Felt, S. A. et al. 2019. A bird's-eye view of regulatory, animal care, and training considerations regarding avian flight research. Comparative Medicine 69(3), 169–178.

A thorough understanding of how animals fly is a central goal of many scientific disciplines. Birds are a commonly used model organism for flight research. The success of this model requires studying healthy and naturally...

Association of Primate Veterinarians. 2019. Association of Primate Veterinarians’ guidelines for nonhuman primate restraint. JAALAS 58(3), 282-284.

The Association of Primate Veterinarians (APV) recognizes that several forms of restraint, including physical and chemical, are necessary for the safe handling of nonhuman primates (NHPs). The following guidelines aim to provide information to researchers...

Giersberg, M. F., Kemper, N., Spindler, B. 2019. On-farm evaluation of an automatic enrichment device with maize silage for laying hens. Journal of Applied Animal Welfare Science 22(4), 309-319.

Challenges in alternative housing for laying hens are barren functional areas such as winter gardens and the occurrence of behavioral disorders. Environmental enrichment is a measure to deal with these problems. Therefore, an enrichment device...

Animal Welfare Institute. 2019. Let’s get serious about animal play. AWI Quarterly 68(3) Fall, 19.

This article describes the importance of providing laboratory animals with opportunities to engage in play, and provides a few practical ideas for how to do this.

Animal Welfare Institute. 2019. Rabbit enrichment items: Getting bang for the buck (and doe). AWI Quarterly 68(1) Spring, 24-25.

A recent discussion on the Laboratory Animal Refinement and Enrichment Forum (LAREF) focused on new enrichment ideas for rabbits. Contributors shared their experiences about which toys and treats get rave reviews from rabbits.

Ali, A. B. A., Campbell, D. L. M., Karcher, D. M. et al. 2019. Daytime occupancy of resources and flooring types by 4 laying hen strains in a commercial-style aviary. Journal of Veterinary Behavior 31, 59-66.

In response to consumer demands and legislative measures for improving hens' welfare, many laying hen producers are replacing conventional cages with aviaries. Aviary resources, such as nest boxes, litter areas, ledges, and perches, are intended...

Marinath, L., Vaz, J., Kumar, D. et al. 2019. Drivers of stereotypic behaviour and physiological stress among captive jungle cat (Felis chaus Schreber, 1777) in India. Physiology & Behavior 210, 112651.

Zoos play a vital role in managing and conserving a wide range of threatened species and in enhancing their populations in natural habitats through captive breeding and reintroduction programmes. Most small felids are poor breeders...

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...

Campderrich, I., Nazar, F. N., Wichman, A. 2019. Environmental complexity: A buffer against stress in the domestic chick. PLOS ONE 14(1), e0210270.

Birds kept in commercial production systems can be exposed to multiple stressors from early life and this alters the development of different morphological, immunological and behavioural indicators. We explore the hypothesis that provision of a...

Ross, M., Garland, A., Harlander-Matauschek, A. et al. 2019. Welfare-improving enrichments greatly reduce hens' startle responses, despite little change in judgment bias. Scientific Reports 9, 11881.

Responses to ambiguous and aversive stimuli (e.g. via tests of judgment bias and measures of startle amplitude) can indicate mammals’ affective states. We hypothesised that such findings generalize to birds, and that these two responses...

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...

Fernandez, E. J., Kinley, R. C., Timberlake, W. 2019. Training penguins to interact with enrichment devices for lasting effects. Zoo Biology 38(6), 481-489.

The modern zoo has brought about two major advances in the behavioral welfare of their exhibited animals: (a) The use of environmental enrichment to promote naturalistic behaviors and (b) the use of training to improve...

Jung, L., Knierim, U. 2019. Differences between feather pecking and non-feather pecking laying hen flocks regarding their compliance with recommendations for the prevention of feather pecking – A matched concurrent case-control design. Applied Animal Behaviour Science 219, 104839.

Feather pecking (FP) is a multifactorial problem in all housing systems. Using a case-control design we wanted to determine a set of variables which may be decisive for a flock to become case or control...

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...