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. 
Spitzer, H. B., Meagher, R. K., Proudfoot, K. L. 2022. The impact of providing hiding spaces to farmed animals: A scoping review. PLOS ONE 17(11), e0277665.

Many wild animals perform hiding behaviours for a variety of reasons, such as evading predators or other conspecifics. Unlike their wild counterparts, farmed animals often live in relatively barren environments without the opportunity to hide...

Houstin, A., Zitterbart, D. P., Winterl, A. et al. 2022. Biologging of emperor penguins—Attachment techniques and associated deployment performance. PLOS ONE 17(8), e0265849.

An increasing number of marine animals are equipped with biologgers, to study their physiology, behaviour and ecology, often for conservation purposes. To minimise the impacts of biologgers on the animals’ welfare, the Refinement principle from...

Chen, Y.-A., Chen, J.-Y., Chen, W.-Q. et al. 2022. Effects of castration age on the growth performance of Nubian crossbred male goats. Animals 12(24), 3516.

To determine the optimal timing for performing castration on goats, eighteen male Nubian crossbred goats were randomly assigned to two groups and castrated at 3 months and 6 months of age, respectively. Daily dry matter...

Ojelade, O. C., Durosaro, S. O., Akinde, A. O. et al. 2022. Environmental enrichment improves the growth rate, behavioral and physiological response of juveniles of Clarias gariepinus under laboratory conditions. Frontiers in Veterinary Science 9, 980364.

Environmental enrichment (EE) improves the growth rate and welfare of some cultured fishes. However, most cultured fish species are raised in non-enriched housing conditions. Clarias gariepinus is an important commercial fish species, but little is...

Prentice, P. M., Houslay, T. M., Wilson, A. J. 2022. Exploiting animal personality to reduce chronic stress in captive fish populations. Frontiers in Veterinary Science 9, 1046205.

Chronic stress is a major source of welfare problems in many captive populations, including fishes. While we have long known that chronic stress effects arise from maladaptive expression of acute stress response pathways, predicting where...

Schwarzer, A., Erhard, M., Schmidt, P. et al. 2022. Effects of stocking rate and environmental enrichment on the ontogeny of pecking behavior of laying hen pullets confined in aviary compartments during the first 4 weeks of life. Animals 12(19), 2639.

The objective of this study was to describe the ontogeny of the severe feather pecking (SFP), gentle feather pecking (GFP), aggressive pecking (AP), and enrichment pecking (EP) of non-beak-trimmed Lohmann Brown (LB)-pullets during the first...

Torgerson-White, L., Sánchez-Suárez, W. 2022. Looking beyond the shoal: Fish welfare as an individual attribute. Animals 12(19), 2592.

Welfare is an individual attribute. In general, providing captive nonhuman animals with conditions conducive to good welfare is an idea more easily applied when dealing with few individuals. However, this becomes much harder—if not impossible—under...

Xu, D., Shu, G., Liu, Y. et al. 2022. Farm animal enrichments improve the welfare of layer chicks and pullets: A comprehensive review. Animals 12(19), 2610.

Currently, cage housing is regarded as a global mainstream production system for laying hens. However, limited living space and confinement of birds in cages cause welfare and health problems, such as feather pecking, osteoporosis, obesity...

Lee, W.-Y., Lan, K.-W., Chang, H.-H. et al. 2022. Residency and swimming behavior of Acanthopagrus schlegelii, Trachinotus blochii, and Acanthopagrus latus in relation to artificial reef models in a captivity experiment. Applied Animal Behaviour Science 257, 105778.

Global capture fisheries production has declined rapidly over the past decades because of the growing demand for fisheries resources. To restore fisheries resources, artificial reefs (ARs) are deployed on the seafloor to provide new habitats...

Riedel, A., Rieke, L., Kemper, N. et al. 2022. A place to be? Use of winter gardens with and without automatic enrichment devices by laying hens. Applied Sciences 12(7), 3650.

Since the abolition of beak trimming in laying hens in Germany, the importance of adequate enrichment material to help reduce feather pecking and cannibalism has grown. Here we tested an automatic enrichment device dosing grain...

Thomas, M., Reynaud, J.-G., Ledoré, Y. et al. 2022. Enrichment in a fish polyculture: Does it affect fish behaviour and development of only one species or both? Applied Sciences 12(7), 3674.

Physical enrichment of structures has been used for the last decades in aquaculture to improve fish production and welfare. Until now, this enrichment has been practiced in fish monoculture but not in fish polyculture. In...

Ramos, J., Balasch, J. C., Tort, L. 2021. About welfare and stress in the early stages of fish. Frontiers in Veterinary Science 8, 634434.

In conclusion, the investigations carried out up to now demonstrate that during the early stages fish show high sensitivity to many types of stressors involving an array of responses to overcome alterations that could affect...

Hempstead, M. N., Shearer, J. K., Sutherland, M. A. et al. 2021. Cautery disbudding iron application time and brain injury in goat kids: A pilot study. Frontiers in Veterinary Science 7, 568750.

Cautery disbudding is a painful procedure performed on goat kids to prevent horn growth that may result in brain injury. Thermal damage to the cerebral cortex of the brain and subsequent neurologic disease is a...

Barretta, L. A., Maloney, S. K., Blachea, D. 2021. Pekin ducks are motivated to access their nest site and exhibit a stress-induced hyperthermia when unable to do so. Animal 15(1), 100067.

The origins of floor-laying in ducks could be low motivation for a nest, or stress related to difficulties with accessing a nest (e.g. competition). Using a behavioural demand test, we investigated if increasing the work...

Stevens, A., Doneley, R., Cogny, A. et al. 2021. The effects of environmental enrichment on the behaviour of cockatiels (Nymphicus hollandicus) in aviaries. Applied Animal Behaviour Science 235, 105154.

Most research to enrich the environment of psittacines in captivity has focused on foraging. Little is known about the importance of bathing substrates for enrichment of their environment, despite this being a natural behaviour that...

Fife-Cook, I., Franks, B. 2021. Koi (Cyprinus rubrofuscus) seek out tactile interaction with humans: General patterns and individual differences. Animals 11(3), 706.

The study of human–animal interactions has provided insights into the welfare of many species. To date, however, research has largely focused on human relationships with captive mammals, with relatively little exploration of interactions between humans...

Zhang, Z., Fu, Y., Zhang, Z. et al. 2021. A comparative study on two territorial fishes: The influence of physical enrichment on aggressive behavior. Animals 11(7), 1868.

Intraspecific aggression is detrimental to body/fin damage, physiological stress, and other problems in aquaculture. Environmental enrichment has been proposed to have positive effects on fish aggressive behavior, physiological stress, and fish welfare, but there are...

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: 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!

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...

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...

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...

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...

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...