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. 
Piller, A., Bergmann, S., Schwarzer, A. et al. 2020. Validation of histological and visual scoring systems for foot-pad dermatitis in broiler chickens. Animal Welfare 29(2), 185-196.

In this study, an appropriate visual scoring system for foot-pad dermatitis was validated, considering the histologically measured depth of the inflammation zone and the histopathological grade (no lesion, mild lesion, ulcer). The aim being to...

Yerpes, M., Llonch, P., Manteca, X. 2020. Factors associated with cumulative first-week mortality in broiler chicks. Animals 10(2), 310.

First-week mortality is an important performance index as well as an important welfare indicator. The aim of the present study was to identify internal (individual-dependent) and external (management or environmental) factors that could influence the...

Jones, P., Tahamtani, F., Pedersen, I. et al. 2020. The productivity and financial impacts of eight types of environmental enrichment for broiler chickens. Animals 10(3), 378.

Reduced mobility in broilers can contribute to leg health problems. Environmental enrichment has been suggested as one approach to combat this through stimulating increased physical activity. Past studies have tested the effect of environmental enrichments...

Guinebretière, M., Mika, A., Michel, V. et al. 2020. Effects of management strategies on non-beak-trimmed laying hens in furnished cages that were reared in a non-cage system. Animals 10(3), 399.

Beak trimming in laying hens limits the negative consequences of injurious pecking, but could be prohibited by future regulations. This study assessed a combination of management strategies during the rearing period (objects, perches, music, human...

Baker, S. L., Robison, C. I., Karcher, D. M. et al. 2020. Keel impacts and associated behaviors in laying hens. Applied Animal Behaviour Science 222, 104886.

Factors contributing to the development of keel bone damage are not well understood. This study aimed to identify behaviors and cage structures associated with acceleration events experienced by individual hens at their keels as the...

Baxter, M., Richmond, A., Lavery, U. et al. 2020. Investigating optimal levels of platform perch provision for windowed broiler housing. Applied Animal Behaviour Science 225, 104967.

Broiler chickens show a preference for platform perches over traditional bar perches. Further information is needed on the optimal provision of these perches in order for them to be successfully installed in commercial systems. This...

Thøfner, I., Hougen, H. P., Villa, C. et al. 2020. Pathological characterization of keel bone fractures in laying hens does not support external trauma as the underlying cause. PLOS ONE 15(3), e0229735.

Keel bone fractures in laying hens have been described with increasing prevalence from several countries over the last twenty years and are considered one of the greatest welfare problems to the layer industry. In Denmark...

Armstrong, E. A., Rufener, C., Toscano, M. J. et al. 2020. Keel bone fractures induce a depressive-like state in laying hens. Scientific Reports 10(1), 3007.

In commercial flocks of laying hens, keel bone fractures (KBFs) are prevalent and associated with behavioural indicators of pain. However, whether their impact is severe enough to induce a depressive-like state of chronic stress is...

Byrnes, E. E., Lear, K. O., Morgan, D. L. et al. 2020. Respirometer in a box: Development and use of a portable field respirometer for estimating oxygen consumption of large‐bodied fishes. Journal of Fish Biology 96(4), 1045-1050.

Respirometry has become the standard method for measuring the metabolic rate of fishes. Traditionally, respirometry has required the fish to be kept in captivity and tested under controlled conditions; however, many species do not readily...

Ross, S. R., Leinwand, J. G. 2020. A review of research in primate sanctuaries. Biology Letters 16(4), 1620200033.

While non-human primate studies have long been conducted in laboratories, and more recently at zoological parks, sanctuaries are increasingly considered a viable setting for research. Accredited sanctuaries in non-range countries house thousands of primates formerly...

Matsuzawa, T. 2020. WISH cages: Constructing multiple habitats for captive chimpanzees. Primates 61(2), 139–148.

This article aims to introduce environmental enrichment for captive chimpanzees in Japan in a historical context. It describes the most recent endeavor of constructing huge cages and connecting multiple habitats. The Ai Project, a series...

Leeds, A., Good, J., Schook, M. W. et al. 2020. Evaluating changes in salivary oxytocin and cortisol following positive reinforcement training in two adult male western lowland gorillas (Gorilla gorilla gorilla). Zoo Biology 39(1), 51-55.

Positive reinforcement training (PRT) is associated with increases in species-typical behavior and decreases in stereotypic and abnormal behavior in participating animals. Physiological changes following PRT, for example, increases in oxytocin (OXT) and/or decreases in cortisol...

Zemanova, M. A. 2020. Towards more compassionate wildlife research through the 3Rs principles: Moving from invasive to noninvasive methods. Wildlife Biology 2020(1), no page numbers.

Research in ecology and wildlife biology remains crucial for increasing our knowledge and improving species management and conservation in the midst of the current biodiversity crisis. However, obtaining information on population status often involves invasive...

Reese, L., Baumgartner, K., von Fersen, L. et al. 2020. Feather corticosterone measurements of greater flamingos living under different forms of flight restraint. Animals 10(4), 605.

Deflighting zoo birds is a practice that receives increasing criticism due to its presumed incompatibility with animal welfare. To our knowledge, this is the first approach to address this problem in a scientific way. To...

Earl, S. C., Hopper, L. M., Ross, S. R. 2020. Same space, different species: The influence of exhibit design on the expression of zoo-housed apes’ species-typical retiring behaviors. Animals 10(5), 836.

Wild chimpanzees frequently make arboreal nests, while wild lowland gorillas typically nest on the ground. We aimed to understand whether zoo-housed apes’ use of elevated spaces for retiring similarly differed between species and across exhibits...

Aleström, P., D’Angelo, L., Midtlyng, P. J. et al. 2020. Zebrafish: Housing and husbandry recommendations. Laboratory Animals 54(3), 213–224.

This article provides recommendations for the care of laboratory zebrafish (Danio rerio) as part of the further implementation of Annex A to the European Convention on the protection of vertebrate animals used for experimental and...

Sharpe, S. A., Scott, S., Taylor, I. et al. 2020. Use of high frequency jet ventilation as a refinement for imaging macaques with respiratory disease. Laboratory Animals 54(4), 386–390.

Imaging is used in human medicine to diagnose disease and monitor treatment efficacy. Computed tomography (CT) positron emission tomography (PET) and magnetic resonance (MR) are applied to animal models of infectious diseases to increase data...

Hedenqvist, P., Trbakovic, A., Mellgren, T. et al. 2020. The effect of housing environment on bone healing in a critical radius defect in New Zealand white rabbits. PLOS ONE 15(5), e0233530.

In animal studies on bone healing, the effect of housing space and physical activity are seldom taken into account. Bone formation was evaluated in New Zealand White rabbits (mean ± SEM BW: 3.9 ± 0.11...

Kneeland, M. R., Spagnuolo, V. A., Evers, D. C. et al. 2020. A novel method for captive rearing and translocation of juvenile common loons. Zoo Biology 39(4), 263–270.

Common loons (Gavia immer) are diving waterbirds that are particularly challenging to keep in captivity due to their specific behavioral and physiologic needs, special housing requirements, and susceptibility to stress‐related disease. We report a novel...

Bari, M. S., Downing, J. A., Dyall, T. R. et al. 2020. Relationships between rearing enrichments, range use, and an environmental stressor for free-range laying hen welfare. Frontiers in Veterinary Science 7, 480.

Enrichments during pullet rearing may improve adaptation and welfare of hens as they move from indoor rearing to a free-range system. Individual variation in outdoor ranging may also affect welfare. This study assessed the effects...

Reinhardt, V. (ed.) 2020. It’s Okay to Cry - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume V. Animal Welfare Institute, Washington, DC.

This is the 5th volume of selected discussions that took place on the electronic Laboratory Animal Refinement & Enrichment Forum between February 2016 and December 2019. The forum was created in October 2002; it allows...

Stracke, J., Klotz, D., Wohlsein, P. et al. 2020. Scratch the surface: Histopathology of foot-pad dermatitis in turkeys (Meleagris gallopavo). Animal Welfare 29(4), 419-432.

Foot-pad dermatitis (FPD) is an important indicator of animal welfare in turkeys (Meleagris gallopavo). The present study aimed to evaluate the reliability and validity of a commonly used five-point visual score (VC), assessing FPD based...

Augustin, A. J., Crabbs, M. A., Sour, M. C. et al. 2020. Efficient, effective, reusable, and customizable social housing for chickens in the laboratory. Laboratory Animal Science Professional 8(5) (September/October), 56-58.

The Iowa State University Laboratory Animal Resources Department needed caging specifically designed and purposed to socially house chickens in the laboratory. As indoor housing requests for chickens increased, the need for a dedicated caging system...

Cloutier Barbour, C., Danforth, M. D., Murphy, H. et al. 2020. Monitoring great ape heart health through innovative electrocardiogram technology: Training methodologies and welfare implications. Zoo Biology 39(6), 443-447.

Assessing and treating cardiovascular disease (or heart disease) is a growing concern for institutions housing great apes, as it is a major cause of mortality in all four taxa managed in human care. As part...

Gebhardt-Henrich, S. G., Jordan, A., Toscano, M. J. et al. 2020. The effect of perches and aviary tiers on the mating behaviour of two hybrids of broiler breeders. Applied Animal Behaviour Science 233, 105145.

Broiler breeders are kept for the production of fertile eggs. They face serious welfare problems like aggressive behaviour of the males towards females during mating. Furthermore, broiler breeders are usually kept without perches which are...