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. 
Kells, N. J., Beausoleil, N. J., Sutherland, M. A. et al. 2018. Electroencephalographic responses of anaesthetised pigs to intraperitoneal injection of sodium pentobarbital. Animal Welfare 27(3), 205-214.

Small laboratory animals are commonly euthanased via intraperitoneal (IP) injection of sodium pentobarbital. However, there is concern that animals may experience pain prior to loss of consciousness with this delivery route. The present study investigated...

Gilliam, J. N., Woods, J., Hill, J. et al. 2018. Evaluation of the CASH Dispatch Kit combined with alternative shot placement landmarks as a single-step euthanasia method for cattle of various ages. Animal Welfare 27(3), 225-233.

Humane euthanasia of cattle under field conditions presents special challenges for veterinarians and producers. The purpose of this study was to evaluate the effectiveness of the CASH Dispatch Kit captive-bolt system combined with improved shot...

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...

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...

Grist, A., Lines, J., Knowles, T. et al. 2018. The use of a non-penetrating captive bolt for the euthanasia of neonate piglets. Animals 8(4), 48.

The most common method for the on-farm euthanasia of neonate piglets is reported to be manual blunt force trauma. This paper presents the results of research to evaluate a mechanical non-penetrating captive bolt (the Accles...

Smith, R., Rault, J., Gates, R. et al. 2018. A two-step process of nitrous oxide before carbon dioxide for humanely euthanizing piglets: On-farm trials. Animals 8(4), 52.

Current methods of euthanizing piglets are raising animal welfare concerns. Our experiment used a novel two-step euthanasia method, using nitrous oxide (N2O) for six minutes and then carbon dioxide (CO2) on compromised 0- to 7-day-old...

Shearer, J. 2018. Euthanasia of cattle: Practical considerations and application. Animals 8(4), 57.

Acceptable methods for the euthanasia of cattle include overdose of an anesthetic, gunshot and captive bolt. The use of anesthetics for euthanasia is costly and complicates carcass disposal. These issues can be avoided by use...

Kells, N., Beausoleil, N., Johnson, C. et al. 2018. Evaluation of different gases and gas combinations for on-farm euthanasia of pre-weaned pigs. Animals 8(3), 40.

The aim of this research was to evaluate the welfare of pre-weaned piglets euthanised using three different gas treatments: 100% carbon dioxide (CO2), 100% argon (Ar) or a mixture of 60% Ar/40% carbon dioxide (Ar/CO2)...

Wallace, C. K., Bright, L. A., Marx, J. O. et al. 2018. Effectiveness of rapid cooling as a method of euthanasia for young zebrafish (Danio rerio). JAALAS 57(1), 58-63.

Despite increased use of zebrafish (Danio rerio) in biomedical research, consistent information regarding appropriate euthanasia methods, particularly for embryos, is sparse. Current literature indicates that rapid cooling is an effective method of euthanasia for adult...

McConnachie, E., Smid, A. M. C., Thompson, A. J. et al. 2018. Cows are highly motivated to access a grooming substrate. Biology Letters 14(8), 20180303.

In natural environments, cattle use trees and other abrasive surfaces to scratch and groom themselves. Modern indoor dairy cattle housing systems often lack appropriate grooming substrates, restricting the animals’ ability to groom. We assessed the...

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...

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...

Grist, A., Knowles, T. G., Wotton, S. B. 2018. Humane euthanasia of neonates II: field study of the effectiveness of the Zephyr EXL non-penetrating captive-bolt system for euthanasia of newborn piglets. Animal Welfare 27(4), 319-326.

A previous study demonstrated the effectiveness of the Bock Industries Zephyr EXL non-penetrating captive bolt, using the abolition of visual-evoked potentials as a determination of brain death, in piglets in a laboratory. A second trial...

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...