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. 
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...

Grist, A., Lines, J., Knowles, T. et al. 2018. Use of a non-penetrating captive bolt for euthanasia of neonate goats. Animals 8(4), 58.

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 goats (Capra aegagrus hircus) of mean...

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)...

Li, Y., Zhang, H., Johnston, L. et al. 2018. Understanding tail-biting in pigs through social network analysis. Animals 8(1), 13.

The objective of this study was to investigate the association between social structure and incidence of tail-biting in pigs. Pigs (n = 144, initial weight = 7.2 ± 1.57 kg, 4 weeks of age) were...

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...

Wiley, J. N., Leeds, A., Carpenter, K. D. et al. 2018. Patterns of wounding in hamadryas baboons (Papio hamadryas) in North American zoos. Zoo Biology 37(2), 74–79.

In North American zoos, hamadryas baboons (Papio hamadryas) have traditionally been housed as single one‐male units (single male groups). In recent years, efforts have been made to house hamadryas in groups composed of multiple one‐male...

Coke, C., Skoumbourdis, E., Rodgers, J. C. et al. 2018. Blunting/cutting canines of adult male monkeys: A discussion by the Laboratory Animal Refinement & Enrichment Forum. Animal Technology & Welfare 17(2), 105-107.

"When you keep adult Rhesus macaque (Macaca mulatta) males, adult Cynomolgus (Macaca fascicularis) males or adult Vervet males (Chlorocebus pygerythrus), in the same enclosure, is it advisable to have the canines of the males blunted...

Verdon, M., Morrison, R. S., Hemsworth, P. H. 2018. Forming groups of aggressive sows based on a predictive test of aggression does not affect overall sow aggression or welfare. Behavioural Processes 150, 17-24.

This experiment examined the effects of group composition on sow aggressive behaviour and welfare. Over 6 time replicates, 360 sows (parity 1–6) were mixed into groups (10 sows per pen, 1.8 m2 /sow) composed of...

Ison, S. H., Bates, R. O., Ernst, C. W. et al. 2018. Housing, ease of handling and minimising inter-pig aggression at mixing for nursery to finishing pigs as reported in a survey of North American pork producers. Applied Animal Behaviour Science 205, 159-166.

Inter-pig aggression is a welfare issue that has undergone extensive research. Although management techniques have proven useful in minimising aggression in research settings, it is not known how often these are used on-farm. One objective...

Peden, R. S. E., Turner, S. P., Boyle, L. A. et al. 2018. The translation of animal welfare research into practice: The case of mixing aggression between pigs. Applied Animal Behaviour Science 204, 1-9.

Aggression between unfamiliar pigs at mixing is a major animal welfare problem in commercial farming. It has been studied since the 1970s and remains an important topic in animal welfare research. Methods to reduce pig...

Zomeño, C., Birolo, M., Gratta, F. et al. 2018. Effects of group housing system, pen floor type, and lactation management on performance and behaviour in rabbit does. Applied Animal Behaviour Science 203, 55-63.

This work aimed at evaluating the effects of housing system, pen floor type, and lactation management on rabbit doe and kit performance throughout a reproductive cycle, including categorization of aggressiveness and injuries. Forty multiparous pregnant...

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...

Franks, B., Graham, C., Von Keyserlingk, M. A. G. 2018. Is heightened-shoaling a good candidate for positive emotional behavior in zebrafish? Animals 8(9), 152.

Zebrafish, a highly-social species of freshwater fish, are widely studied across many fields of laboratory science including developmental biology, neuroscience, and genomics. Nevertheless, as standard housing for zebrafish typically consists of small and simplistic environments...

Camerlink, I., Farish, M., D’Eath, R. B. et al. 2018. Long term benefits on social behaviour after early life socialization of piglets. Animals 8(11), 192.

Early life socialization of piglets has been shown to reduce piglet aggression at weaning, but information on sow health and long-term benefits is lacking. We aimed to assess how socialization impacts sow udder quality and...

Salazar, L. C., Ko, H.-L., Yang, C.-H. et al. 2018. Early socialisation as a strategy to increase piglets’ social skills in intensive farming conditions. Applied Animal Behaviour Science 206, 25-31.

Socialisation is a process in which animals interact with unfamiliar conspecifics, that allows them to develop their social abilities. Socialisation has been proposed as a method in pig husbandry to increase piglets’ social skills and...

Thurston, S., Burlingame, L., Lester, P. A. et al. 2018. Methods of pairing and pair maintenance of New Zealand white rabbits (Oryctolagus Cuniculus) via behavioral ethogram, monitoring, and interventions. JoVE (Journal of Visualized Experiments) 133, e57267.

Though European rabbits are a social species, socially housing them can be challenging. Therefore, there must be a thorough understanding of behaviors and social structures of pair-housed laboratory rabbits. Here we present a protocol to...

González-Pech, P. G., Marín-Tun, C. G., Valladares-González, D.A. et al. 2018. A protocol of human animal interaction to habituate young sheep and goats for behavioural studies. Behavioural Processes 157, 632-637.

Animal habituation is key to obtain reliable data on behavioural studies but detailed procedures to achieve it are scarce. This study designed a set of actions to habituate sheep and goats to human observers. Pelibuey...

Nawroth C., Albuquerque N., Savalli C. et al. 2018. Goats prefer positive human emotional facial expressions. Royal Society Open Science 5(8), 180491.

Domestication has shaped the physiology and the behaviour of animals to better adapt to human environments. Therefore, human facial expressions may be highly informative for animals domesticated for working closely with people, such as dogs...

Camacho, J., Morris, J. 2018. Breaking down the barriers: Social housing of previously single-housed adult baboons. Laboratory Animal Science Professional 5(4) (December), 55-57.

An important responsibility of each institution is to challenge preconceived notions that may limit social housing. At our institution’s center for comparative medicine (CCM), we recently challenged a historical mindset that 2 large (>25 kg)...

Gut, W., Crump, L., Zinsstag, J. et al. 2018. The effect of human interaction on guinea pig behavior in animal-assisted therapy. Journal of Veterinary Behavior 25, 56-64.

Guinea pigs are included in various animal-assisted interventions (AAIs), but no research has been published to date on behavioral changes in guinea pigs interacting with humans. The goal of this study was to evaluate the...

Sutherland, M. A., Watson, T. J., Millman, S. T. 2017. Technical contribution: evaluation of the efficacy of a non-penetrating captive bolt to euthanase dairy goat kids up to 30 days of age. Animal Welfare 26(3), 277-280.

The objective of this study was to evaluate the effectiveness of a non-penetrating captive bolt (NPCB) to euthanase previously disbudded Saanen dairy goat kids (Capra hircus) up to 30 days of age and 9 kg...

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...