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. 
Backus, B. L., McGlone, J. J. 2018. Evaluating environmental enrichment as a method to alleviate pain after castration and tail docking in pigs. Applied Animal Behaviour Science 204, 37-42.

Castration and tail docking are common management practices performed on commercial swine farms in the US and around the world to reduce adverse behaviors and the occurrence of boar taint. However, these practices themselves are...

Yang, C.-H., Ko, H.-L., Salazar, L. C. et al. 2018. Pre-weaning environmental enrichment increases piglets’ object play behaviour on a large scale commercial pig farm. Applied Animal Behaviour Science 202, 7-12.

Environmental enrichment is a legal requirement for European pig farms. The suitability of enrichment materials for neonatal pigs is understudied and has not been tested in commercial settings. This study investigates the effect of hanging...

Rosvold, E. M., Newberry, R. C., Framstad, T. 2018. Nest-building behaviour and activity budgets of sows provided with different materials. Applied Animal Behaviour Science 200, 36-44.

Domestic sows are still highly motivated to build a nest before farrowing. Many pig houses have slurry systems that do not allow use of long straw or other bulky materials that could block the drains...

Wondrak, M., Conzelmann, E., Veit, A. et al. 2018. Pigs (Sus scrofa domesticus) categorize pictures of human heads. Applied Animal Behaviour Science 205, 19-27.

Scientists as well as farmers are increasingly interested in the mental capacities of pigs. Recent research has revealed surprising cognitive abilities, such as episodic memory, intentional deception and even theory of mind. Still, our knowledge...

Colpoys, J. D., Johnson, A. K., Gabler, N. K. 2018. The efficacy of novel rope flavours as environmental enrichment for stalled gilts. Animal Welfare 27(4), 351-356.

The objective of this study was to evaluate the use of flavoured ropes as environmental enrichment for individually housed pigs (Sus scrofa). A 4 × 4 Latin square experimental design was utilised to evaluate the...

Peveler, J. L., Hickman, D. L. 2018. Effects of music enrichment on individually housed male New Zealand white rabbits. JAALAS 57(6), 695–697.

The beneficial effect of music has been demonstrated in many species. Although commercially available music CDs intended for use with rabbits are available, these enrichments have not been critically evaluated to determine whether they reduce...

Schild, S.-L. A., Rangstrup-Christensen, L., Bonde, M. et al. 2018. The use of a shaded area during farrowing and lactation in sows kept outdoors. Applied Animal Behaviour Science 209, 22-29.

The hut temperature in outdoor pig production during summer can exceed the upper critical temperature of lactating sows. Therefore, sows may experience hyperthermia, a condition which has several adverse consequences for the welfare of both...

Brown, S.M., Bush, S.J., Summers, K.M. et al. 2018. Environmentally enriched pigs have transcriptional profiles consistent with neuroprotective effects and reduced microglial activity. Behavioural Brain Research 350, 6-15.

Environmental enrichment (EE) is widely used to study the effects of external factors on brain development, function and health in rodent models, but very little is known of the effects of EE on the brain...

Perdue, B. M., Beran, M. J., Washburn, D. A. 2018. A computerized testing system for primates: Cognition, welfare, and the Rumbaughx. Behavioural Processes 156, 37-50.

Innovations in apparatus technology come about for a variety of reasons such as the need to use the same methodology with various species, the opportunity to present dynamic and carefully controlled stimuli, the goal of...

Mkwanazi, M. V., Kanengoni, A. T., Chimonyo, M. 2018. Pen enrichment and sex interaction on growth performance and metabolite concentrations of autochthonous Windsnyer pigs kept in a high stocking density. Canadian Journal of Animal Science 98(4), 826-832.

The objective of the study was to determine the interaction of pen enrichment and sex on growth performance and blood metabolite concentrations of Windsnyer pigs. Forty-eight growing Windsnyer pigs of both sexes, with an average...

Collymore, C., Kent, L., Ahn, S. K. et al. 2018. Humane endpoints for guinea pigs used for Mycobacterium tuberculosis vaccine research. Comparative Medicine 68(1), 41–47.

Guinea pigs are a commonly used model for tuberculosis vaccine research. Loss of body weight is the most frequently described humane endpoint for animals used in these studies. During a chronic study, we noted labored...

Wolfe, A. M., Rahman, M., McFadden, D. G. et al. 2018. Refinement and successful implementation of a scoring system for myxomatosis in a susceptible rabbit (Oryctolagus cuniculus) model. Comparative Medicine 68(4), 280–285.

Myxoma virus is a member of Leporipoxviridae whose tropism is tightly restricted to lagomorphs. In susceptible Oryctolagus rabbits, the virus causes a highly lethal disease known as myxomatosis, which begins as a localized infection but...

Bulens, A., Van Beirendonck, S., Van Thielen, J. et al. 2018. Rearing finishing pigs with intact tails: Do they benefit from an enriched environment? Journal of Veterinary Behavior 24, 1-8.

In an attempt to prevent tail biting in pigs, tail docking is often done. This management procedure is painful for the pigs, so the question arises whether pigs can be raised with intact tails and...

Heyworth, C., Olivo, D. 2018. Environmental and psychological enrichment for NHPs reimagined and repurposed. Laboratory Animal Science Professional 5(4) (December), 39-43.

This article describes creative enrichment ideas for nonhuman primates, including celery stalks embedded with seeds; paper rolled into tubes, braided and filled with fruit and seeds; pineapple crowns loaded with treats; dry spaghetti noodles coated...

Iske, C. J., Morris, C. L., Colpoys, J. D. et al. 2018. Nutrient evaluation of a pork by-product and its use as environmental enrichment for managed large exotic cats. PLOS ONE 13(9), e0202144.

North American zoological institutions typically feed ground raw meat diets to large exotic cats. These diets typically are nutritionally complete, but lack physical properties characteristic of whole prey. Lack of mastication and prey manipulation may...

French, F., Mancini, C., Sharp, H. 2018. High tech cognitive and acoustic enrichment for captive elephants. Journal of Neuroscience Methods 300, 173-183.

This paper investigates the potential for using technology to support the development of sensory and cognitive enrichment activities for captive elephants. It explores the usefulness of applying conceptual frameworks from interaction design and game design...

Machado, S. P., Caldara, F. R., Foppa, L. et al. 2017. Behavior of pigs reared in enriched environment: Alternatives to extend pigs attention. PLOS ONE 12(1), e0168427.

Three trials were carried out in a completely randomized design aiming to assess the behavior of pigs in growth phase in enriched environments. Trial 1 evaluated the effects of frequency of availability of environmental enrichment...

Sommerville, R., Ruiz, R., Averós, X. 2017. A meta-analysis on the effects of the housing environment on the behaviour, mortality, and performance of growing rabbits. Animal Welfare 26(2), 223-238.

Although the number of rabbits (Oryctolagus cuniculus) produced in Europe is important, they are under-represented in welfare research. Studies on the effects of housing conditions have focused on performance and mortality. We conducted a meta-analysis...

Winfield, J., Macnamara, G., Macnamara, B. et al. 2017. Environmental enrichment for sucker and weaner pigs: The effect of enrichment block shape on the behavioural interaction by pigs with the blocks. Animals 7(12), 91.

This experiment tested the effect of enrichment-block shape on oro-nasal contact by young pigs, and possible habituation to the blocks. Nineteen litters (197 piglets) were randomly allocated to one of three block-shape treatments: Cube, Brick...

Vermeer, H., Dirx-Kuijken, N., Bracke, M. 2017. Exploration feeding and higher space allocation improve welfare of growing-finishing pigs. Animals 7(5), 36.

Lack of environmental enrichment and high stocking densities in growing-finishing pigs can lead to adverse social behaviors directed to pen mates, resulting in skin lesions, lameness, and tail biting. The objective of the study was...

Backus, B. L., Sutherland, M. A., Brooks, T. A. 2017. Relationship between environmental enrichment and the response to novelty in laboratory-housed pigs. JAALAS 56(6), 735-741.

Environmental enrichment is the enhancement of the physical or social environment in which an animal lives with the goal to improve its quality of life. Our objective was to investigate the effect of providing environmental...

Brown, S. M., Peters, R., Lawrence, A. B. 2017. Up-regulation of IGF-1 in the frontal cortex of piglets exposed to an environmentally enriched arena. Physiology & Behavior 173, 285-292.

Environmental enrichment (EE) is widely used in the life sciences to study effects of environment on the brain. In pigs, despite lack of EE being a key welfare issue there is little understanding of brain...

Palmer, S. 2017. Rescue-Enrich-Release: The environmental enrichment program for three species of captive primates at Colobus. Canopy 17(2), 27-30.

It is widely known that the psychological wellbeing of captive animals can become compromised by a captive environment that lacks proper environmental stimulation. Environmental enrichment programs have become the norm in captive environments yet research...

Alligood, C. A., Dorey, N. R., Mehrkam, L. R. et al. 2017. Applying behavior-analytic methodology to the science and practice of environmental enrichment in zoos and aquariums. Zoo Biology 36(3), 175–185.

Environmental enrichment in zoos and aquariums is often evaluated at two overlapping levels: published research and day‐to‐day institutional record keeping. Several authors have discussed ongoing challenges with small sample sizes in between‐groups zoological research and...

Damasceno, J., Genaro, G., Quirke, T. et al. 2017. The effects of intrinsic enrichment on captive felids. Zoo Biology 36(3), 186–192.

Environmental enrichment is a well‐known technique, which has been used to enhance the welfare of captive animals. The aim of this study is to investigate how three different forms of intrinsic enrichment, namely, a hay...