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. 
Fels, M., Lüthje, F., Faux-Nightingale, A. et al. 2018. Use of space and behavior of weaned piglets kept in enriched two-level housing system. Journal of Applied Animal Welfare Science 21(3), 267-282.

In this study, the possibility of introducing an elevated platform to a piglet pen was explored as a way of increasing available space and creating functional areas. On the platform, nine different manipulable materials were...

Perez, B. C., Mehrkam, L. R., Foltz, A. R. et al. 2018. Effects of enrichment presentation and other factors on behavioral welfare of pantropical spotted dolphin (Stenella attenuata). Journal of Applied Animal Welfare Science 21(2), 130-140.

Environmental enrichment is a crucial element of promoting welfare for animals in captivity. However, enrichment programs are not always formally evaluated for their efficacy. Furthermore, there is little empirical evidence of enrichment evaluation for species...

Ralph, C., Hebart, M., Cronin, G. 2018. Enrichment in the sucker and weaner phase altered the performance of pigs in three behavioural tests. Animals 8(5), 74.

We tested the hypothesis that provision of enrichment in the form of enrichment blocks during the sucker and weaner phases would affect the behaviour of pigs. We measured the performance of pigs in an open...

Lutz, C. K., Brown, T. A. 2018. Porches as enrichment for singly housed cynomolgus macaques (Macaca fascicularis). JAALAS 57(2), 138-142.

Effective environmental enrichment is used by animals, promotes species-typical behavior, and decreases abnormal behavior. Porches attached to the front of an animal's cage provide additional space, perching opportunities, and a better view of the surroundings...

Chatigny, F., Creighton, C. M., Stevens, E. D. 2018. Updated review of fish analgesia. JAALAS 57(1), 5-12.

Analgesics are an integral part of routine pain management in mammals, yet their use in fish is still limited. Some recommendations on the use of analgesics in fish are currently in the literature; however, information...

Cabana, F., Maguire, R., Hsu, C-D. et al. 2018. Identification of possible nutritional and stress risk factors in the development of marmoset wasting syndrome. Zoo Biology 37(2), 98–106.

Marmoset wasting syndrome (MWS) describes a series of symptoms in callitrichids that lead to general weakness and a failure to thrive in captive conditions such as zoological institutions. Though the cause of MWS has not...

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...

Graham, C., von Keyserlingk, M. A. G., Franks, B. 2018. Free-choice exploration increases affiliative behaviour in zebrafish. Applied Animal Behaviour Science 203, 103-110.

Cognitive stimulation has been shown to be rewarding and capable of eliciting positive emotions in several species. In contrast to the abundant learning and exploration opportunities available in nature, captive environments can be under-stimulating—with the...

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...

de Almeida A. C., Palme, R., Moreira, N. 2018. How environmental enrichment affects behavioral and glucocorticoid responses in captive blue-and-yellow macaws (Ara ararauna). Applied Animal Behaviour Science 201, 125-135.

Captive animals are susceptible to chronic stress due to restricted space, lack of hiding places, presence of visitors, or the lack of resources that promote physical and mental stimuli. In birds, chronic stress can promote...

Graham, C., von Keyserlingk, M. A. G., Franks, B. 2018. Zebrafish welfare: Natural history, social motivation and behaviour. Applied Animal Behaviour Science 200, 13-22.

Zebrafish are now one of the most used animal model species in scientific research worldwide. Our current knowledge of wild zebrafish is limited to an estimated range of their natural habitats and their tendencies to...

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...

Brown, T. A., Lutz, C. K., 2018. An assessment of porches as enrichment for singly housed cynomolgus macaques (Macaca fascicularis). American Journal of Primatology 80(S1), 18 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #21).

Effective environmental enrichment encourages usage, promotes species‐typical behaviors, and/or decreases abnormal behaviors. Porches are small cages that attach to the primary cage of an animal to provide additional space and a better view of the...

Perlman, J. E., Martin, A. L., Bloomsmith, M. A., 2018. Increases in feeding and destructible enrichment distribution in caged rhesus macaques (Macaques mulatta) provide some behavioral benefits. American Journal of Primatology 80(S1), 19 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #24).

It is important to evaluate the effectiveness of environmental enrichment in meeting behavioral goals (e.g., decreasing abnormal behavior) and in making the best use of limited facility resources (e.g., money, personnel time). One/zero behavioral data...

Woelffer, S., Ace, L., Sullivan, J. et al., 2018. Enhanced physical environment in single-housed macaques: A long-term usage profile of cage extensions. American Journal of Primatology 80(S1), 19-20 (40th Meeting of the American Society of Primatologists Scientific Program, Abstract #25).

Social housing is always preferred in the research environment; however, single housing is sometimes necessitated by scientific objectives or social incompatibility. In these cases, other environmental enhancements are developed to provide indirect social interactions. We...

Yoshimoto, T., Takahashi, E., Yamashita, S. et al. 2018. Larger cages with housing unit environment enrichment improve the welfare of marmosets. Experimental Animals 67(1), 31-39.

The provision of adequate space for laboratory animals is essential not only for good welfare but accurate studies. For example, housing conditions for primates used in biomedical research may negatively affect welfare and thus the...

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...

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...

Lee, C. J., Tyler, C. R., Paull, G. C. et al. 2018. Can simple tank changes benefit the welfare of laboratory zebrafish Danio rerio? Journal of Fish Biology 92(3), 653-659.

This study examined the effects of simple changes in the tank environment on the wellbeing of laboratory-maintained zebrafish Danio rerio. Groups of D. rerio were either housed in stable environments (where they were maintained in...

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...