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. 
Stanger, K. J., Kells, N. J., Fisher, A. D. et al. 2019. Evaluation of euthanasia of sheep with intravenous saturated salt solutions to enable the collection of whole, intact brains. Animal Welfare 28(4), 397-406.

Captive bolts or firearms are unsuitable for euthanasia of livestock when an intact brain is required for diagnostics. Injectable barbiturates can be used, but this method carries risk of poisoning animals eating the carcase. Intravenous...

Bouwsema, J. A., Lines, J. A. 2019. Could low atmospheric pressure stunning (LAPS) be suitable for pig slaughter? A review of available information. Animal Welfare 28(4), 421-432.

Low atmospheric pressure stunning (LAPS) is a slaughter technique which may be less stressful for pigs (Sus scrofa domestica) than current commercial stunning and slaughter methods. The main methods used currently for slaughtering pigs are...

Steiner, A. R., Axiak Flammer, S., Beausoleil, N. J. et al. 2019. Humanely ending the life of animals: Research priorities to identify alternatives to carbon dioxide. Animals 9(11), 911.

The use of carbon dioxide (CO2) for stunning and killing animals is considered to compromise welfare due to air hunger, anxiety, fear, and pain. Despite decades of research, no alternatives have so far been found...

McNamara, A., Allen, L. 2019. Bottle or bowl? Feeding and dosing in juvenile Göttingen minipigs. Animal Technology and Welfare 18(2), 153-154. (IAT Congress 2018 Poster Presentation)

The Laboratory Animal Technology department at Envigo were engaged to perform a toxicity study in juvenile Göttingen Minipigs. The test compound was a human milk formula additive. Therefore, to mimic the conditions of clinical administration...

Baker, S. W., Tucci, E. R., Felt, S. A. et al. 2019. A bird's-eye view of regulatory, animal care, and training considerations regarding avian flight research. Comparative Medicine 69(3), 169–178.

A thorough understanding of how animals fly is a central goal of many scientific disciplines. Birds are a commonly used model organism for flight research. The success of this model requires studying healthy and naturally...

Association of Primate Veterinarians. 2019. Association of Primate Veterinarians’ guidelines for nonhuman primate restraint. JAALAS 58(3), 282-284.

The Association of Primate Veterinarians (APV) recognizes that several forms of restraint, including physical and chemical, are necessary for the safe handling of nonhuman primates (NHPs). The following guidelines aim to provide information to researchers...

Cross, N. 2019. A code of welfare for horses and donkeys: establishing standards for the welfare of equids in New Zealand. Journal of Veterinary Behavior 29, 148-149. (13th International Society of Equitation Science (ISES) Conference Abstract)

New Zealand’s code of welfare for horses and donkeys was developed by the National Animal Welfare Advisory Committee (NAWAC), under provisions in the Animal Welfare Act 1999, and issued by the Minister for Primary Industries...

Cox, R. J., Nol, P., Ellis, C. K. et al. 2019. Research with agricultural animals and wildlife. ILAR Journal 60(1), 66-73.

In fiscal year 2016, agricultural animals such as swine, sheep, goats, and cattle represented 10% of the 820 812 animals used in USDA-regulated research. In addition to traditional agricultural animals, research studies using captive wildlife...

Colby, L. A., Nowland, M. H., Kennedy, L. H. 2019. Clinical Laboratory Animal Medicine: An Introduction (5th ed). Wiley-Blackwell, Ames, IA.

The revised fifth edition of Clinical Laboratory Animal Medicine: An Introduction is an accessible guide to basic information for conducting animal research safely and responsibly. It includes a review of the unique anatomic and physiologic...

Stomp, M., Leroux, M., Cellier, M. et al. 2018. An unexpected acoustic indicator of positive emotions in horses. PLOS ONE 13(7), e0197898.

Indicators of positive emotions are still scarce and many proposed behavioural markers have proven ambiguous. Studies established a link between acoustic signals and emitter’s internal state, but few related to positive emotions and still fewer...

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...

Maigrot, A., Hillmann, E., Briefer, E. 2018. Encoding of emotional valence in wild boar (Sus scrofa) calls. Animals 8(6), 85.

Measuring emotions in nonhuman mammals is challenging. As animals are not able to verbally report how they feel, we need to find reliable indicators to assess their emotional state. Emotions can be described using two...

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...

Grist, A., Lines, J., Knowles, T. et al. 2018. The use of a mechanical non-penetrating captive bolt device for the euthanasia of neonate lambs. Animals 8(4), 49.

A non-penetrating captive bolt device, powered by a 1-grain 0.22″ cartridge delivering a calculated kinetic energy of 47 Joules was tested as a euthanasia method on 200 neonate lambs (Ovis aries) of 4.464 kg (SD...

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...

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)...

McGreevy, P., Berger, J., de Brauwere, N. et al. 2018. Using the five domains model to assess the adverse impacts of husbandry, veterinary, and equitation interventions on horse welfare. Animals 8(3), 41.

The aim of this study was to conduct a series of paper-based exercises in order to assess the negative (adverse) welfare impacts, if any, of common interventions on domestic horses across a broad range of...

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...

Mason, A., Tolo, E., Hektoen, L. et al. 2018. The effect of electrical head-to-chest stunning on the EEG in sheep. Animal Welfare 27(4), 343-350.

Head-to-body stunning is regarded as ‘best practice’ stunning for sheep. The benefits are loss of consciousness followed by cardiac arrest, death, prevention of animal movements post stun/kill and improved meat quality. Commercial equipment places electrodes...

Sutherland, M. A., Bryer, P. J., Backus, B. L. 2017. The effect of age and method of gas delivery on carbon dioxide euthanasia of pigs. Animal Welfare 26(3), 293-299.

The objectives of this research were to evaluate the effect of age and delivering method during carbon dioxide (CO2) euthanasia on the welfare of pigs (Sus scrofa). In Experiment 1, pigs aged 1, 2, 3...

Grist, A., Murrell, J. C., McKinstry, J. L. et al. 2017. Humane euthanasia of neonates I: validation of the effectiveness of the Zephyr EXL non-penetrating captive-bolt euthanasia system on neonate piglets up to 10.9 kg live-weight. Animal Welfare 26(1), 111-120.

To determine if mechanical blunt force trauma using a non-penetrating captive bolt was a viable method of producing an immediate stun/kill in neonate piglets (Sus scrofa domesticus) as an alternative to manual blunt force trauma...

Walsh, J., Percival, A., Turner, P. 2017. Efficacy of blunt force trauma, a novel mechanical cervical dislocation device, and a non-penetrating captive bolt device for on-farm euthanasia of pre-weaned kits, growers, and adult commercial meat rabbits. Animals 7(12), 100.

The commercial meat rabbit industry is without validated on-farm euthanasia methods, potentially resulting in inadequate euthanasia protocols. We evaluated blunt force trauma (BFT), a mechanical cervical dislocation device (MCD), and a non-penetrating captive bolt device...

Leliveld, L. M. C., Düpjan, S., Tuchscherer, A. et al. 2017. Vocal correlates of emotional reactivity within and across contexts in domestic pigs (Sus scrofa). Physiology & Behavior 181, 117-126.

Vocalizations have long been recognized to encode information about an individual's emotional state and, as such, have contributed to the study of emotions in animals. However, the potential of vocalizations to also encode information about...

McMillan, J. L., Bloomsmith, M. A., Prescott, M. J. 2017. An international survey of approaches to chair restraint of nonhuman primates. Comparative Medicine 67(5), 442–451.

Specifically designed restraint chairs are the preferred method of restraint for research studies that require NHP to sit in place for sustained periods of time. In light of increasing emphasis on refinement of restraint to...

Ali, A. B. A., Gutwein, K. L., Heleski, C. R. 2017. Assessing the influence of upper lip twitching in naive horses during an aversive husbandry procedure (ear clipping). Journal of Veterinary Behavior 21, 20-25.

When engaging in procedures that horses may find aversive, restraint methods are often used to help ensure safety of both horse and handler. Twitching is a common restraint method, but its use is sometimes considered...