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. 
Sandilands, V., Baker, L., Donbavand, J. et al. 2021. Effects of different scratch mat designs on hen behaviour and eggs laid in enriched cages. Animals 11(6), 1544.

Laying hens in the UK and EU must be provided with litter for pecking and scratching. In enriched cages, this is commonly provided by dispensing layer’s feed onto a scratch mat. Mats vary in design...

Whittaker, A. L., Golder-Dewar, B., Triggs, J. L. et al. 2021. Identification of animal-based welfare indicators in captive reptiles: A Delphi consultation survey. Animals 11(7), 2010.

There is an increasing focus on evidence-based welfare assessment by animal care staff in zoos, along with a strong interest in animal welfare by the zoo-visiting public, to the extent that this can influence their...

Nagabaskaran, G., Burman, O. H. P., Hoehfurtner, T. et al. 2021. Environmental enrichment impacts discrimination between familiar and unfamiliar human odours in snakes (Pantherophis guttata). Applied Animal Behaviour Science 237, 105278.

Environmental enrichment has been found to significantly influence the cognitive abilities of a variety of mammalian and avian species, with effects ranging from positive to negative, however, these effects have been little studied in reptiles...

Hoehfurtner, T., Wilkinson, A., Nagabaskaran, G. et al. 2021. Does the provision of environmental enrichment affect the behaviour and welfare of captive snakes? Applied Animal Behaviour Science 239, 105324.

There is a wealth of evidence demonstrating the benefits of environmental enrichment across a range of different animal species. However, there is comparatively little such research into the effect of enrichment provision on captive reptiles...

Malchow, J., Schrader, L. 2021. Effects of an elevated platform on welfare aspects in male conventional broilers and dual-purpose chickens. Frontiers in Veterinary Science 8, 660602.

To avoid killing day-old male chicks, one possibility is to keep dual-purpose chicken strains. Here, the hens were kept for egg production, and the roosters were kept for meat production. Both sexes had moderate performances...

Lambert, K. 2021. DIY: Acacia gum sealed paper straws. Laboratory Animal Science Professional 9(3) (May/June), 37.

This DIY snack is great for NHP and can be customized in a variety of ways.

Lambert, K. 2021. DIY: Dehydrated watermelon training chips. Laboratory Animal Science Professional 9(4) (July/August), 48.

This simple DIY training treat is great for NHP, swine, rabbits, rodents, and dogs. Note that dehydrated watermelon may resemble muscle tissue!

Hollandt, T., Baur, M., Wöhr, A.-C. 2021. Animal-appropriate housing of ball pythons (Python regius)—Behavior-based evaluation of two types of housing systems. PLOS ONE 16(5), e0247082.

Considering animal welfare, animals should be kept in animal-appropriate and stress-free housing conditions in all circumstances. To assure such conditions, not only basic needs must be met, but also possibilities must be provided that allow...

Kittelsen, K. E., Gretarsson, P., Jensen, P. et al. 2021. Keel bone fractures are more prevalent in White Leghorn hens than in Red Jungle fowl hens—A pilot study. PLOS ONE 16(7), e0255234.

Fractures and deviations to the keel bone are common in commercial laying hens, with reported variations in occurrence across strains and breeds. The aetiology is not fully understood, however, modern genetics and selection for efficient...

Norman, K. I., Weeks, C. A., Tarlton, J. F. 2021. Rearing experience with ramps improves specific learning and behaviour and welfare on a commercial laying farm. Scientific Reports 11(1), 8860.

To access resources in commercial laying houses hens must move between levels with agility to avoid injury. This study considered whether providing ramps during rear improved the ability of birds to transition between levels. Twelve...

Robbins, R. L., Sheridan, J. 2021. Effect of enclosure expansion on the activity budgets of eastern black-and-white colobus monkeys, Colobus guereza. Zoo Biology 40(2), 115-123.

Behavior is one of the most observable and informative indicators of animal welfare. This study used behavioral observation methodologies to evaluate the impact of an enclosure expansion on the activity budgets of a group of...

McDonald, M. M., Agnew, M. K., Asa, C. S. et al. 2021. Melengestrol acetate contraceptive implant use in colobus monkeys (Colobus guereza): Patterns through time and differences in reproductive potential and live births. Zoo Biology 40(2), 124-134.

Melengestrol acetate (MGA) implants are progestin-based reversible contraceptives used to manage fertility in zoo populations. Although it is recommended that MGA implants should be replaced every 2 years, the duration of efficacy has not been...

Diarra, S., Lameta, S., Amosa, F. et al. 2021. Alternative bedding materials for poultry: Availability, efficacy, and major constraints. Frontiers in Veterinary Science 8, 669504.

The increasing demand of wood shavings (WS) and sawdust (SD) by other industries and growing concerns of potential chemical contaminants from wood products have amplified research interest in alternative bedding materials for commercial poultry. Several...

Campbell, D. L. M., Whitten, J. M., Slater, E. et al. 2021. Rearing enrichments differentially modified hen personality traits and reduced prediction of range use. Animal Behaviour 179, 97-109.

Domestic fowl have been demonstrated to individually differ in personality, dictating reactions to environmental stimuli. Free-range chickens, Gallus gallus domesticus, show individual range use variation, which may be related to personality differences. Enrichment can also...

Peploe, J., MacAulay, C. 2021. Laboratory primate enrichment ideas. Animal Technology and Welfare 20(2), 177-183.

There are several items we often use in animal facilities that when finished with are thrown away. However, many of these items come in packaging that can be recycled as enrichment for our animals, particularly...

Sans, E. C. O., Tuyttens, F. A.M., Taconeli, C. A. et al. 2021. Welfare of broiler chickens reared under two different types of housing. Animal Welfare 30(3), 341-353.

We compared closed- and open-sided industrial houses with respect to the welfare of broiler chickens in southern Brazil. Ten flocks from each design were evaluated and measures divided into the following categories: i) bird health...

Anderson, M. G., Campbell, A. M., Crump, A. et al. 2021. Effect of environmental complexity and stocking density on fear and anxiety in broiler chickens. Animals 11(8), 2383.

Barren housing and high stocking densities may contribute to negative affective states in broiler chickens, reducing their welfare. We investigated the effects of environmental complexity and stocking density on broilers’ attention bias (measure of anxiety)...

Fernández-Lázaro, G., Dye, M. H., Eddie,C. et al. 2021. Strepsirrhine primate training programs in North American institutions: Status and implications for future welfare assessment. Animals 11(8), 2462.

Many articles have shown the benefits of operant conditioning training techniques in the care and welfare of several species of nonhuman primates; however, the information regarding their use in strepsirrhine species is scarce. We assessed...

Alejandro, J., Yamanashi, Y., Nemoto, K. et al. 2021. Behavioral changes of solitary housed female pygmy slow lorises (Nycticebus pygmeaus) after introduction into group enclosures. Animals 11(9), 2751.

Pygmy slow lorises (Nycticebus pygmaeus) are threatened with extinction in the wild. Their nocturnal lifestyle and small size make them difficult to study in their natural habitat, but increasing evidence suggests that they are more...

Travain, T., Valsecchi, P. 2021. Infrared thermography in the study of animals’ emotional responses: A critical review. Animals 11(9), 2510.

Whether animals have emotions was historically a long-lasting question but, today, nobody disputes that they do. However, how to assess them and how to guarantee animals their welfare have become important research topics in the...

Jacobs, L., Melick, S., Freeman, N. et al. 2021. Broiler chicken behavior and activity are affected by novel flooring treatments. Animals 11(10), 2841.

The objective was to determine broiler chicken behavioral differences in response to novel flooring treatments. Broilers (n = 182) were housed in 14 pens (a random subset from a larger-scale study including 42 pens), with...

Schwarzer, A., Plattner, C., Bergmann, S. et al. 2021. Feather pecking in non-beak-trimmed and beak-trimmed laying hens on commercial farms with aviaries. Animals 11(11), 3085.

Severe feather pecking (SFP) is a major animal welfare problem in layers. It results in pain and injuries in the affected animal. It was the aim of this study to gain insight into the actual...

Diana, A., Salas, M., Pereboom, Z. et al. 2021. A systematic review of the use of technology to monitor welfare in zoo animals: Is there space for improvement? Animals 11(11), 3048.

A top priority of modern zoos is to ensure good animal welfare (AW), thus, efforts towards improving AW monitoring are increasing. Welfare assessments are performed through more traditional approaches by employing direct observations and time-consuming...

Hu, J., Xiong, Y., Gates, R. S. et al. 2021. Perches as cooling devices for reducing heat stress in caged laying hens: A review. Animals 11(11), 3026.

Heat stress is one of the most detrimental environmental challenges affecting the biological process and the related production performance of farm animals, especially in poultry. Commercial laying hens have been bred (selected) for high egg...

de Jong, I. C., Blaauw, X. E., van der Eijk, J. E. J. et al. 2021. Providing environmental enrichments affects activity and performance, but not leg health in fast- and slower-growing broiler chickens. Applied Animal Behaviour Science 241, 105375.

Effects of environmental enrichment on activity, behaviour, walking ability, contact dermatitis and performance were investigated in fast- and slower-growing broiler chickens. A total of 840 day-old male broilers, 420 of a fast-growing strain (Ross 308)...