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. 
Fynn, M., Crow, G., Connor, L. 2021. Pre-farrow enrichment with burlap sheet: potential benefit for sow performance. Canadian Journal of Animal Science 101(4), 781-787.

Burlap has been proposed as an enrichment option for the conventional farrowing crate environment. Our objectives were to determine if burlap sheets hung in farrowing crates were used by sows and piglets and had any...

Strappini, A. C., Monti, G., Sepúlveda-Varas, P. et al. 2021. Measuring calves' usage of multiple environmental enrichment objects provided simultaneously. Frontiers in Veterinary Science 8, 698681.

This study aims to assess calf usage of five potential enrichment devices provided simultaneously. We used 25 weaned Holstein-Friesian calves housed in groups of five (five replicates), and their behavior was recorded continuously with video...

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...

Schodl, K., Wiesauer, L., Winckler, C. et al. 2021. Reduced stocking density and provision of straw in a rack improve pig welfare on commercial fattening farms. Frontiers in Veterinary Science 8, 656211.

The aim of this study was to investigate the impact of reduced stocking density in combination with provision of additional enrichment material on pig welfare on-farm. On three growing-finishing farms in Austria, in total 974...

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...

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...

Vinícius dos Santos, J., de Souza Farias, S., Pereira, T. L. et al. 2021. Preference for and maintenance of interest in suspended enrichment toys in confined growing pigs. Journal of Veterinary Behavior 45, 68-73.

The objective of the present study was to evaluate the preference for, interest in, and behavior of growing pigs provided with three different suspended enrichment toys in a four-compartment environmental preference chamber (EPC). Sixty pigs...

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...

Lambert, K. 2021. DIY: Acacia gum hanging saucer. Laboratory Animal Science Professional 9(5) (September/October), 50.

This article describes the ingredients, supplies, and directions to make this DIY hanging item, which is great for NHP and swine.

Merley, A. L., Duke Boynton, F. D. 2021. Design and construction of a low-cost mirror for enrichment of socially isolated pigs. Laboratory Animal Science Professional 9(5) (September/October), 56-57.

Due to their social needs, every effort should be made to house pigs with compatible conspecifics; however, there may be instances where due to experimental or veterinary concerns, single housing is necessary. In those situations...

Lambert, K. 2021. DIY: Busy boxes. Laboratory Animal Science Professional 9(6) (November/December), 32.

This article describes the ingredients and directions to make this simple DIY destructible enrichment for NHP and swine.

Miller, L. J., Lauderdale, L. K., Mellen, J. D. et al. 2021. Assessment of animal management and habitat characteristics associated with social behavior in bottlenose dolphins across zoological facilities. PLOS ONE 16(8), e0253732.

Bottlenose dolphins are a behaviorally complex, social species that display a variety of social behaviors. Because of this, it is important for zoological facilities to strive to ensure animals display species-appropriate levels of social behavior...

Lauderdale, L. K., Mellen, J. D., Walsh, M. T. et al. 2021. Towards understanding the welfare of cetaceans in accredited zoos and aquariums. PLOS ONE 16(8), e0255506.

Cetaceans are long-lived, social species that are valued as ambassadors inspiring the public to engage in conservation action. Under professional care, they are critical partners with the scientific community to understanding the biology, behavior, physiology...

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...

Lauderdale, L. K., Shorter, K. A., Zhang, D. et al. 2021. Habitat characteristics and animal management factors associated with habitat use by bottlenose dolphins in zoological environments. PLOS ONE 16(8), e0252010.

The way an animal uses its habitat can serve as an indicator of habitat appropriateness for the species and individuals. Bottlenose dolphins (Tursiops truncatus and Tursiops aduncus) in accredited zoos and aquariums experience a range...

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...

Misra, S., Bokkers, E., Upton, J. et al. 2021. Effect of environmental enrichment and group size on the water use and waste in grower-finisher pigs. Scientific Reports 11(1), 16380.

The grower-finisher stage accounts for 64% of the total on-farm herd water use. Part of this is consumed by the pigs, but a part is also wasted. Drinking water usage and wastage is affected by...

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...

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...