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. 
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...

Sanchez-Casanova, R., Sarmiento-Franco, L., Segura-Correa, J. et al. 2019. Effects of outdoor access and indoor stocking density on behaviour and stress in broilers in the subhumid tropics. Animals 9(12), 1016.

Studies investigating the welfare of commercial-line broiler chickens raised in houses with outdoor access in the tropics are scarce, and none have investigated whether responses vary according to indoor conditions. Hence, we assessed the effects...

Hubert, S., Al-Ajeeli, M., Bailey, C. et al. 2019. The role of housing environment and dietary protein source on the gut microbiota of chicken. Animals 9(12), 1085.

The gut microbiota of chicken has received much attention due to its importance for bird health, food safety, and performance. In the United States, the impending transition to cage-free housing environments has raised many questions...

Cooke, G. M., Tonkins, B. M., Mather, J. A. 2019. Care and enrichment for captive cephalopods. In: The Welfare of Invertebrate Animals. Carere, C., Mather, J. (eds), 179-208. Springer, Cham.

Cephalopods have become an archetype for invertebrate cognition, sentience and welfare studies. Their convergence with so-called ‘higher’ vertebrates (birds, mammals) in memory, learning, problem-solving, tool use and likely sentience has made biologists completely rethink the...

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...

Eusemann, B. K., Baulain, U., Schrader, L. et al. 2018. Radiographic examination of keel bone damage in living laying hens of different strains kept in two housing systems. PLOS ONE 13(5), e0194974.

A high prevalence of deviations and fractures of the keel bone is a widespread welfare problem in laying hens. The aim of this study was to experimentally investigate this multifactorial problem throughout the laying period...

Toscano, M., Booth, F., Richards, G. et al. 2018. Modeling collisions in laying hens as a tool to identify causative factors for keel bone fractures and means to reduce their occurrence and severity. PLOS ONE 13(7), e0200025.

Keel fractures represent a major productivity and welfare issue for the laying hen industry with greater than 50% of birds in recent surveys across various commercial operations and nations exhibiting some form of damage by...

Santurtun, E., Broom, D. M., Phillips, C. J. C. 2018. A review of factors affecting the welfare of Atlantic salmon (Salmo salar). Animal Welfare 27(3), 193-204.

In the expanding salmon industry, many farmers use production methods that could result in poor welfare of the fish at various points of their lifecycle. We have reviewed methods used for producing salmon for food...

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...

Zloch, A., Kuchling, S., Hess, M. et al. 2018. Influence of alternative husbandry systems on postmortem findings and prevalence of important bacteria and parasites in layers monitored from end of rearing until slaughter, Veterinary Record 182(12), 350.

In the present study 66 layer flocks housed in different alternative husbandry systems were monitored from placement of birds on the farm until slaughter to evaluate a possible influence on the occurrence of selected non-infectious...

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...

Chen, S., Xiang, H., Zhu, X. et al. 2018. Free dietary choice and free-range rearing improve the product quality, gait score, and microbial richness of chickens. Animals 8(6), 84.

Poultry welfare has been extensively studied; however, there is a lack of rigorous scientific knowledge relating to the different aspects of welfare factors and how this may contribute to the production quantity and product quality...

Smith, L., Hallager, S., Kendrick, E. et al. 2018. Husbandry of wild-caught song sparrows (Melospiza melodia). Zoo Biology 37(3), 206–209.

Conservation and research efforts occasionally rely upon bringing wild animals into human care to establish breeding programs and to understand their biology. Wild‐caught birds may have husbandry requirements that differ from captive‐reared animals due, in...

Hunniford, M. E., Mason, G. J., Widowski, T. M. 2018. Laying hens’ preferences for nest surface type are affected by enclosure. Applied Animal Behaviour Science 201, 7-14.

The nest surfaces preferred by hens are inconsistent with those typically provided in commercial settings. However, little research has explored hens’ preferences for commercially available nest surfaces. Our objective was to compare hens’ preferences for...

Sirovnik, J., Stratmann, A., Gebhardt-Henrich, S. G. et al. 2018. Feeding from perches in an aviary system reduces aggression and mortality in laying hens. Applied Animal Behaviour Science 202, 53-62.

Some commercial aviary systems for laying hens allow birds to access feed by standing on perches instead of platforms. Despite reports that providing laying hens with perches relates to reduced aggression and cannibalism, and increased...

Sirovnik, J., Würbel, H., Toscano, M. J. 2018. Feeder space affects access to the feeder, aggression, and feed conversion in laying hens in an aviary system. Applied Animal Behaviour Science 198, 75-82.

In laying hens, minimal requirements for feeder space (cm per bird) are based primarily on data from small groups of hens (n

Jung, L., Knierim, U. 2018. Are practice recommendations for the prevention of feather pecking in laying hens in non-cage systems in line with the results of experimental and epidemiological studies? Applied Animal Behaviour Science 200, 1-12.

Feather pecking (FP) in laying hens is an important animal welfare problem in practice, despite extensive research and increasing sources of advice for farmers. We aimed to give an overview over results from experimental and...

Baxter, M., Bailie, C. L., O’Connell, N. E. 2018. Evaluation of a dustbathing substrate and straw bales as environmental enrichments in commercial broiler housing. Applied Animal Behaviour Science 200, 78-85.

The use of straw bales as an environmental enrichment is common for broiler chickens in enriched housing systems, however relatively little information exists about their effectiveness in improving welfare. There has also been no widespread...

James, C., Asher, L., Herborn, K. et al. 2018. The effect of supplementary ultraviolet wavelengths on broiler chicken welfare indicators. Applied Animal Behaviour Science 209, 55-64.

Qualities of the light environment are important for good welfare in a number of species. In chickens, UVA light is visible and may facilitate flock interactions. UVB wavelengths promote endogenous vitamin D synthesis, which could...

Egbuniwe, I. C., Ayo, J. O., Kawu, M. U. et al. 2018. Behavioral and hematological responses of broiler chickens administered with betaine and ascorbic acid during hot-dry season. Journal of Applied Animal Welfare Science, 21(4), 334-346.

Heat stress is a major problem in poultry production in tropical regions. Assessing the impact of thermally stressful environmental conditions on the welfare of broiler chickens is of great importance. Behavioral responses in a novel...

Lopes, A. C. C., Villacorta-Correa, M. A., Carvalho, T. B. 2018. Lower light intensity reduces larval aggression in matrinxã, Brycon amazonicus. Behavioural Processes 151, 62-66.

Brycon amazonicus shows a high frequency of aggressive behavior, which can be a limiting factor in intensive farming systems. Environmental changes can modulate the social interactions of fish and reduce aggression during the different stages...

Kennedy, R. J., Allen, M., Wilson, R. 2018. Tag retention and mortality of adult Atlantic salmon Salmo salar gastrically tagged with different sized telemetry transmitters. Journal of Fish Biology 92(6), 2016-2021.

A batch of 1 sea winter pre-spawning adult Salmo salar from the Bush river in Northern Ireland, U.K., were gastrically tagged with large (13-mm diameter) and small (9-mm diameter) dummy acoustic telemetry tags alongside untagged...

Fenkes, M., Shiels, H. A., Nudds, R. L. 2018. Body shape and robustness response to water flow during development of brown trout Salmo trutta parr. Journal of Fish Biology 93(2), 360-369.

Domesticated brown trout Salmo trutta parr were subjected to increased, variable flow under controlled experimental conditions. Using geometric morphometric analyses, (a mass:length index) and caudal fin area:body length ratio, this study assessed morphological responses in...

Riley, W. D., Ibbotson, A. T., Gregory, S. D. et al. 2018. Under what circumstances does the capture and tagging of wild Atlantic salmon Salmo salar smolts affect probability of return as adults? Journal of Fish Biology 93(3), 477-489.

Adult return rates for wild Atlantic salmon Salmo salar smolts captured in a rotary screw trap and tagged with coded wire (CW) tags were compared with a control group, using detections from passive integrated transponder...

Zepp, M., Louton, H., Erhard, M. et al. 2018. The influence of stocking density and enrichment on the occurrence of feather pecking and aggressive pecking behavior in laying hen chicks. Journal of Veterinary Behavior 24, 9-18.

The housing conditions and environments experienced during the rearing period can influence the development of feather pecking in chickens during this time and in the subsequent laying period. The aim of this study was to...