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. 
Forslind, S., Blokhuis, H. J., Riber, A. B. 2021. Disturbance of resting behaviour of broilers under different environmental conditions. Applied Animal Behaviour Science 242, 105425.

Resting behaviours make up a large part of the daily time budget of broilers. However, in intensive broiler production systems disruptions of resting behaviours occur, where resting individuals get disturbed by active individuals. Such interruptions...

Sirovnik, J., Euteneuer, P., König von Borstel, U. 2021. An attempt to use sound-imprinting to attract broilers onto elevated platforms for night-time roosting. Applied Animal Behaviour Science 243, 105448.

Welfare of fast growing broilers is often compromised due to leg health issues. A more complex environment such as the provision of elevated platforms facilitates activity and improves leg health in fast growing broilers. Thus...

MacLellan, A., Fureix, C., Polanco, A. et al. 2021. Can animals develop depression? An overview and assessment of “depression-like” states. Behaviour 158(14/15), 1303–1353.

Describing certain animal behaviours as 'depression-like' or 'depressive' has become common across several fields of research. These typically involve unusually low activity or unresponsiveness and/or reduced interest in pleasure (anhedonia). While the term 'depression-like' carefully...

Campbell, D. L. M., Lee, C. 2021. A perspective on strategic enrichment for brain development: Is this the key to animal happiness? Frontiers in Veterinary Science 8, 720422.

Livestock animals are sentient beings with cognitive and emotional capacities and their brain development, similar to humans and other animal species, is affected by their surrounding environmental conditions. Current intensive production systems, through the restrictions...

Neethirajan, S. 2021. The use of artificial intelligence in assessing affective states in livestock. Frontiers in Veterinary Science 8, 715261.

In order to promote the welfare of farm animals, there is a need to be able to recognize, register and monitor their affective states. Numerous studies show that just like humans, non-human animals are able...

Falendysz, E. A., Calhoun, D. M., Smith, C. A. et al. 2020. Outside the box: Working with wildlife in biocontainment. ILAR Journal 61(1), 72-85.

Research with captive wildlife in Animal Biosafety Level 2 (ABSL2) and 3 (ABSL3) facilities is becoming increasingly necessary as emerging and re-emerging diseases involving wildlife have increasing impacts on human, animal, and environmental health. Utilizing...

da Silva Medeiros Elidio, H., Coelho, J. W. R., Cavalcanti Pereira da Silva, L. C. et al. 2021. Housing density and aggression in Syrian hamsters. JAALAS 60(5), 506-509.

The Syrian hamster (Mesocricetus auratus) is a solitary and naturally territorial animal, with female hamsters being more aggressive than males. This behavior makes handling difficult because they are usually housed in groups, which can lead...

de A. P. Ramos, G., de Azevedo, C. S., Jardim, T. H. A. et al. 2021. Temperament in captivity, environmental enrichment, flight ability, and response to humans in an endangered parrot species. Journal of Applied Animal Welfare Science 24(4), 379-391.

Temperament assessment is useful in reintroduction programs. Reactivity to humans and flight ability are also important behavioral aspects for captive parrots candidates to reintroduction. The study aimed: a) to evaluate if behavioral responses to environmental...

James, C., Nicholls, A., Freeman, M. et al. 2021. Should zoo foods be chopped: Macaws for consideration. Journal of Zoo and Aquarium Research, 9(4), 200-207.

Globally, many zoological collections provide their animals with diets that are chopped into small chunks, yet there is limited empirical research to measure the benefits of this practice. Preparing chopped diets takes considerable amounts of...

Razal, C., Miller, L. 2021. The effect of different types of environmental enrichment on Humboldt penguin Spheniscus humboldti behaviour. Journal of Zoo and Aquarium Research, 9(4), 281-286.

Penguins exhibited at zoological institutions can be prone to a foot condition known as pododermatitis (or bumblefoot) if they have high levels of sedentary behaviour. Providing penguins with environmental enrichment can increase activity levels by...

Lourenço da Silva, M. I., Almeida Paz, I., Chaves, G. et al. 2021. Behaviour and animal welfare indicators of broiler chickens housed in an enriched environment. PLOS ONE 16(9), e0256963.

The present study aimed to assess the influence of adding straw bales, step platforms, and laser projectors as environmental enrichment resources on the behaviour and welfare indicators of broiler chickens (Gallus gallus domesticus). A sample...

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...

Thatcher, D. 2021. The use of a borescope for Goodfellow’s tree kangaroo (Dendrolagus goodfellowi) husbandry. RATEL (Journal of the Association of British and Irish Wild Animal Keepers) 48(2), 10-11.

In 2017 Bristol Zoological Gardens received two Goodfellow tree kangaroos. As this was a new marsupial species for the collection, keepers attended the European Symposium on tree kangaroos to better improve our husbandry, knowledge and...

Brox, B. W., Edwards, K., Buist, N. A. et al. 2021. Investigating food preference in zoo-housed meerkats. Zoo Biology 40(6), 517-526.

Understanding food preference among animals in human care can support improvements to welfare through training and day-to-day care (e.g., diet management). Little has been published about food preference in zoo-housed meerkats. Assessing meerkat food preference...

Podturkin, A. A. 2021. In search of the optimal enrichment program for zoo-housed animals. Zoo Biology 40(6), 527-540.

Zoo-housed animals are regularly exposed to new forms of environmental enrichment to make their lives less predictable. However, providing new enrichment can have unpredictable effects. We evaluated the effectiveness of two enrichment regimes: (1) providing...

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...

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...

Mellor, E. L., McDonald Kinkaid, H. K., Mendl, M. T. et al. 2021. Nature calls: Intelligence and natural foraging style predict poor welfare in captive parrots. Proceedings of the Royal Society B: Biological Sciences 288(1960), 20211952

Understanding why some species thrive in captivity, while others struggle to adjust, can suggest new ways to improve animal care. Approximately half of all Psittaciformes, a highly threatened order, live in zoos, breeding centres and...

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...

Costantino, A., Fabrizio, E., Calvet, S. 2021. The role of climate control in monogastric animal farming: The effects on animal welfare, air emissions, productivity, health, and energy use. Applied Sciences 11(20), 9549.

In the last decades, an engineering process has deeply transformed livestock houses by introducing fine-tuned climate control systems to guarantee adequate indoor climate conditions needed to express the maximum genetic potential of animals and to...

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...

Waterman, J. O., McNally, R., Harrold, D. et al. 2021. Evaluating environmental enrichment methods in three zoo-housed varanidae lizard species. Journal of Zoological and Botanical Gardens 2(4), 716–727.

Environmental enrichment has been shown to enhance the behavioural repertoire and reduce the occurrence of abnormal behaviours, particularly in zoo-housed mammals. However, evidence of its effectiveness in reptiles is lacking. Previously, it was believed that...

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...