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. 
Vaglio, S., Kaburu, S. S. K., Pearce, R. et al. 2021. Effects of scent enrichment on behavioural and physiological indicators of stress in zoo primates. American Journal of Primatology 83(5), e23247.

Captive breeding is vital for primate conservation, with modern zoos serving a crucial role in breeding populations of threatened species and educating the general public. However, captive populations can experience welfare issues that may also...

Adler, C., Schmithausen, A. J., Trimborn, M. et al. 2021. Effects of a partially perforated flooring system on ammonia emissions in broiler housing—Conflict of objectives between animal welfare and environment? Animals 11(3), 707.

A partially (50%) perforated flooring system showed positive effects on health- and behavior-based welfare indicators without affecting production performance. Ammonia (NH3) is the most common air pollutant in poultry production, with effects on animal welfare...

Phillips, H. N., Heins, B. J. 2021. Effects of outdoor stocking density on growth, feather damage and behavior of slow-growing free-range broilers. Animals 11(3), 688.

Access to pasture is a main benefit of free-range broiler housing systems, yet the level of outdoor stocking density on broiler animal welfare remains unsettled. The growth, feather damage, pasture ranging and behaviors were assessed...

Wichman, A., De Groot, R., Håstad, O. et al. 2021. Influence of different light spectrums on behaviour and welfare in laying hens. Animals 11(4), 924.

Artificial commercial lighting used in animal production facilities can have negative influences on visual abilities, behaviour and welfare of domestic fowl. This study examined the effects of natural-derived light spectrums on behaviour, production and welfare...

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...

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!

Huber, N., Mahr, K., Tóth, Z. et al. 2021. The stressed bird in the hand: Influence of sampling design on the physiological stress response in a free-living songbird. Physiology & Behavior 238, 113488.

Despite the widely used application of standardized capture-handling protocols to collect blood and assess the physiological stress response, the actual sampling design (e.g., timing and the number of blood samples) often differs between studies, and...

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...

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...

Archibald, W., Glynn, C. 2021. Refining cages for social housing of non-human primates on ADME studies. Animal Technology and Welfare 20(2), 172-174.

The assessment and understanding of Absorption, Distribution, Metabolism and Elimination (ADME) for new pharmaceuticals is required in regulatory submissions. Typically, ADME studies are conducted using metabolism cages designed for the single housing of animals to...

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)...

Grün, S., Damme, K., Müller, M. et al. 2021. Welfare and performance of three turkey breeds—Comparison between infrared beak treatment and natural beak abrasion by pecking on a screed grinding wheel. Animals 11(8), 2395.

Feather pecking and cannibalism are behavioral disorders that cause animal-welfare-relevant and economic problems. To mitigate these problems, the beaks of conventionally reared turkeys are usually already trimmed in the hatcheries. To find an alternative to...

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...

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...

Seeley, K. E., Proudfoot, K. L., Wolfe, B. et al. 2021. Assessing allostatic load in ring-tailed lemurs (Lemur catta). Animals 11(11), 3074.

Responses to stress are unavoidable, adaptive mechanisms in humans and non-human animals. However, in humans, chronic stress has been linked to poor health outcomes and early mortality. Allostatic load, the physiologic dysregulation that occurs when...

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...