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. 
Eusemann, B. K., Baulain, U., Schrader, L. et al. 2018. Radiographic examination of keel bone damage in living laying hens of different strains kept in two housing systems. PLOS ONE 13(5), e0194974.

A high prevalence of deviations and fractures of the keel bone is a widespread welfare problem in laying hens. The aim of this study was to experimentally investigate this multifactorial problem throughout the laying period...

Toscano, M., Booth, F., Richards, G. et al. 2018. Modeling collisions in laying hens as a tool to identify causative factors for keel bone fractures and means to reduce their occurrence and severity. PLOS ONE 13(7), e0200025.

Keel fractures represent a major productivity and welfare issue for the laying hen industry with greater than 50% of birds in recent surveys across various commercial operations and nations exhibiting some form of damage by...

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...

Kallio, P. A, Janczak, A. M., Valros, A. E. et al. 2018. Case control study on environmental, nutritional and management-based risk factors for tail-biting in long-tailed pigs. Animal Welfare 27(1), 21-34.

A case control study with a questionnaire was carried out to compare feeding practices, diet composition, housing and management in 78 herds with or without a history of tail-biting in undocked pigs (Sus scrofa) in...

Clarke, T., Pluske, J. R., Miller, D. W. et al. 2018. Parity influences the demeanor of sows in group housing. Journal of Applied Animal Welfare Science 21(1), 17-26.

Across the globe, producers are moving from individual housing to group housing for sows during gestation. Producers typically group sows of a range of parities together, although the impacts are largely unknown. This study examined...

Benson, E., Weiher, J., Alphin, R. et al. 2018. Evaluation of two compressed air foam systems for culling caged layer hens. Animals 8(5), 61.

Outbreaks of avian influenza (AI) and other highly contagious poultry diseases continue to be a concern for those involved in the poultry industry. In the situation of an outbreak, emergency depopulation of the birds involved...

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)...

Martin, J., Sandercock, D., Sandilands, V. et al. 2018. Welfare risks of repeated application of on-farm killing methods for poultry. Animals 8(3), 39.

Council Regulation (EC) no. 1099/2009 on the protection of animals at the time of killing restricts the use of manual cervical dislocation in poultry on farm in the European Union (EU) to birds weighing up...

Gurung, S., White, D., Archer, G. et al. 2018. Evaluation of alternative euthanasia methods of neonatal chickens. Animals 8(3), 37.

Hatched male layer chicks are currently euthanized by maceration in the United States. Public concerns on the use of maceration have led to the search for alternative methods. We hypothesized that gas inhalation and low...

Martin, J., Sandilands, V., Sparrey, J. et al. 2018. On farm evaluation of a novel mechanical cervical dislocation device for poultry. Animals 8(1), 10.

Urgent development of alternative on-farm killing methods for poultry is required following the number restrictions placed on the use of traditional manual cervical dislocation by European Legislation (EU 1099/2009). Alternatives must be proven to be...

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...

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...

Jung, L., Knierim, U. 2018. Are practice recommendations for the prevention of feather pecking in laying hens in non-cage systems in line with the results of experimental and epidemiological studies? Applied Animal Behaviour Science 200, 1-12.

Feather pecking (FP) in laying hens is an important animal welfare problem in practice, despite extensive research and increasing sources of advice for farmers. We aimed to give an overview over results from experimental and...

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...

Kittelsen, K. E., Granquist, E. G., Aunsmo, A. L. et al. 2018. An evaluation of two different broiler catching methods. Animals 8(8), 141.

Catching is the first step in the pre-slaughter chain for broiler chickens. The process may be detrimental for animal welfare due to the associated handling. The aim of this pilot study was to compare two...

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...