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. 
Redaelli, V., Bosi, A., Luzi, F. et al. 2021. Neuroinflammation, body temperature and behavioural changes in CD1 male mice undergoing acute restraint stress: An exploratory study. PLOS ONE 16(11), e0259938.

Background: Animal models used to study pathologies requiring rehabilitation therapy, such as cardiovascular and neurologic disorders or oncologic disease, must be as refined and translationally relevant as possible. Sometimes, however, experimental procedures such as those...

Winn, C. B., Hwang, S. K., Morin, J. et al. 2021. Automated monitoring of respiratory rate as a novel humane endpoint: A refinement in mouse metastatic lung cancer models. PLOS ONE 16(9), e0257694.

In oncology research, while xenograft tumor models are easily visualized and humane endpoints can be clearly defined, metastatic tumor models are often based on more subjective clinical observations as endpoints. This study aimed at identifying...

Janhunen, M., Piironen, J., Vainikka, A. et al. 2021. The effects of environmental enrichment on hatchery-performance, smolt migration and capture rates in landlocked Atlantic salmon. PLOS ONE 16(12), e0260944.

Enrichment of rearing environment with natural elements has been suggested to improve the welfare and post-release survival of cultured fish. We studied the combined effects of shelter structures, periodical water flow and water level changes...

Ratuski, A. S., Makowska, I. J., Dvorack, K. R. et al. 2021. Using approach latency and anticipatory behaviour to assess whether voluntary playpen access is rewarding to laboratory mice. Scientific Reports 11(1), 18683.

Laboratory mice are typically housed in “shoebox" cages that limit the expression of natural behaviours. Temporary access to more complex environments (playpens) may improve their welfare. We aimed to assess if access to playpens is...

Anderson, M. G., Campbell, A. M., Crump, A. et al. 2021. Environmental complexity positively impacts affective states of broiler chickens. Scientific Reports 11(1), 16966.

Affective state can bias an animal’s judgement. Animals in positive affective states can interpret ambiguous cues more positively (“optimistically”) than animals in negative affective states. Thus, judgement bias tests can determine an animal’s affective state...

Wood, B., Rufener, C., Makagon, M. M. et al. 2021. The utility of scatter feeding as enrichment: Do broiler chickens engage with scatter–fed items? Animals 11(12), 3478.

In recent years, welfare certification companies have encouraged the use of scatter feeding as enrichment material, though there is little scientific evidence to support a scatter feeding program. This study aimed to understand the impact...

Ciborowska, P., Michalczuk, M., Bień, D. 2021. The effect of music on livestock: Cattle, poultry and pigs. Animals 11(12), 3572.

The welfare of animals, especially those kept in intensive production systems, is a priority for modern agriculture. This stems from the desire to keep animals healthy, to obtain a good-quality final product, and to meet...

Miller, A. L., Roughan, J. V. 2021. Welfare assessment, end-point refinement and the effects of non-aversive handling in C57BL/6 mice with Lewis lung cancer. Animals 12(1), 23.

Cancer-bearing mice are at risk of developing anxiety, pain, or malaise. These conditions may not only harm welfare but could also undermine data quality and translational validity in studies to develop therapeutic interventions. We aimed...

Güz, B. C., de Jong, I. C., Da Silva, C. S. et al. 2021 Effects of pen enrichment on leg health of fast and slower-growing broiler chickens. PLOS ONE 16(12), e0254462.

Pen enrichment for broiler chickens is one of the potential strategies to stimulate locomotion and consequently contribute to better leg health and welfare. This study was designed to evaluate effects of using a plethora of...

Brereton, J. E., Myhill, M. N. G., Shora, J. A. 2021. Investigating the effect of enrichment on the behavior of zoo-housed southern ground hornbills. Journal of Zoological and Botanical Gardens 2(4), 600–609.

Enrichment is essential for the welfare of many zoo-housed animals, yet the value of enrichment is not well understood for all taxa. As an intelligent, long-lived species, the southern ground hornbill (Bucorvus leadbeateri) is a...

Fernandez, E. J., Myers, M., Hawkes, N. C. 2021. The effects of live feeding on swimming activity and exhibit use in zoo Humboldt penguins (Spheniscus humboldti). Journal of Zoological and Botanical Gardens 2(1), 88–100.

Penguins are considered among the most popular animals for zoo and aquarium visitors to observe. Swimming is considered a desirable activity, both for the visitor experience and the welfare of the penguins. However, little is...

Kalafut, K. L., Kinley, R. 2020. Using radio frequency identification for behavioral monitoring in little blue penguins. Journal of Applied Animal Welfare Science 23(1), 62-73.

A common goal of captive animal institutions is to create environments that allow for the most naturalistic behavior from their animals. Behavioral data is often used as a measure of how an animal is thriving...

Glaspell, S. 2020. Flight to freedom: Behavior modification of an undomesticated pigeon using human interaction. Laboratory Animal Science Professional 8(2) (March/April), 58-61.

The white-crowned pigeon, Patagioenas leucocephala, is a species of bird not often used in research. This may be related to its anxiety during normal human interactions, such as with cage changing. Our institution acquired a...

Fangmeier, M. L., Burns, A. L., Melfi, V. A. et al. 2020. Foraging enrichment alleviates oral repetitive behaviors in captive red-tailed black cockatoos (Calyptorhynchus banksii). Zoo Biology 39(1), 3-12.

The relationship between inadequate foraging opportunities and the expression of oral repetitive behaviors has been well documented in many production animal species. However, this relationship has been less-well examined in zoo-housed animals, particularly avian species...

Campbell, D., Gerber, P., Downing, J. et al. 2020. Minimal effects of rearing enrichments on pullet behaviour and welfare. Animals 10(2), 314.

In Australia, free-range pullets are typically reared indoors, which may hinder later adjustment to outdoor access. Rearing enrichments could optimise pullet development. Hy-Line Brown® chicks (n = 1700) were reared indoors across 16 weeks with...

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...

van den Oever, A. C. M., Rodenburg, T. B., Bolhuis, J. E. et al. 2020. Relative preference for wooden nests affects nesting behaviour of broiler breeders. Applied Animal Behaviour Science 222, 104883.

Optimising nest design for broiler breeders has benefits for both the animals and the producers. The welfare of the hens will increase by providing preferred housing, while also reducing eggs laid outside the nests. These...

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...

Guijarro, A., Mauri, S., Aviles, C. et al. 2020. Effects of two CO2 stunning methods on the efficacy of stunning and blood stress indicators of turkeys under commercial processing conditions. Journal of Applied Animal Welfare Science 23(2), 231-243.

The effect of CO2 gas-stunning methods (G1: 30% CO2 15 sec, 55% CO2 40 sec, 70% CO2 45 sec; G2: 30% CO2 15 sec, 80% CO2 85 sec) on the efficacy of stunning, blood stress...

Gehlen, H., Loschelder, J., Merle, R. et al. 2020. Evaluation of stress response under a standard euthanasia protocol in horses using analysis of heart rate variability. Animals 10(3), 485.

The effects of a standard protocol for euthanasia on heart rate variability (HRV) as a consequence of stress response were analyzed in this prospective clinical study. The HRV was determined in 40 horses undergoing euthanasia...

Regaiolli, B., Angelosante, C., Marliani, G. et al. 2020. Gum feeder as environmental enrichment for zoo marmosets and tamarins. Zoo Biology 39(2), 73-82.

Tamarins and marmosets are small-bodied social callitrichines. Wild callitrichines feed on exudates, such as sap and gum; particularly, marmosets are mainly gummivores, while tamarins consume gums only occasionally and opportunistically. Zoo marmosets and tamarins are...

da Silva, A., Lima, M. R., Meletti, P. C. et al. 2020. Impact of environmental enrichment and social group size in the aggressiveness and foraging activity of Serrapinnus notomelas. Applied Animal Behaviour Science 224, 104943.

Fish are widely used in scientific research, and many species are bred for ornamental purposes and human consumption. Despite the large number of fish kept in captivity, research on the welfare of these animals has...

Mertens, S., Gass, P., Palme, R. et al. 2020. Effect of a partial cage dividing enrichment on aggression-associated parameters in group-housed male C57BL/6NCrl mice. Applied Animal Behaviour Science 224, 104939.

Group-housing is highly important for social animals. Group-housing of male mice in captivity though often leads to aggression with partially disastrous consequences for the animals as well as for the quality of experimental data. In...