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. 
Wotton, S., Grist, A., O’Callaghan, M. et al. 2020. Head-only stunning of turkeys Part 1: The minimum voltage necessary to break down the inherent high resistance. Animals 10(12), 2427.

Pre-slaughter stunning is required for humane slaughter. For turkeys, head-only electrical stunning is most often used by small scale producers. To ensure immediate and effective stunning, the impedance (resistance) of the tissue of the head...

Lindahl, C., Sindhøj, E., Brattlund Hellgren, R. et al. 2020. Responses of pigs to stunning with nitrogen filled high-expansion foam. Animals 10(12), 2210.

Nitrogen gas (N2) delivered in high expansion foam in a closed container could be a feasible method for humanely stunning pigs. This study aimed to evaluate potential aversion in pigs to the N2 foam method...

Pedersen, I. J., Forkman, B. 2019. Improving leg health in broiler chickens: A systematic review of the effect of environmental enrichment. Animal Welfare 28(2), 215-230.

Leg problems are highly prevalent in modern broiler production and provision of environmental enrichment could be a strategy to improve leg health. Different types of environmental enrichment have undergone evaluation. Our objective was to conduct...

Jacobs, L., Bourassa, D. V., Harris, C. E. et al. 2019. Euthanasia: Manual versus mechanical cervical dislocation for broilers. Animals 9(2), 47.

The aim was to assess the onset of brain stem death for two euthanasia methods—manual cervical dislocation (CD) versus the Koechner Euthanizing Device (KED). Over three days broilers of 36 (n = 60), 42 (n...

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...

Bandara, R. M.A.S., Torrey, S., Turner, P. V. et al. 2019. Efficacy of a novel mechanical cervical dislocation device in comparison to manual cervical dislocation in layer chickens. Animals 9(7), 407.

The main objective of this study was to assess the efficacy of mechanical cervical dislocation using the Koechner Euthanasia Device Model C (KED) in comparison to manual cervical dislocation in layer chickens. Laying hens and/or...

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...

Cornale, P., Macchi, E., Miretti, S. et al. 2015. Effects of stocking density and environmental enrichment on behavior and fecal corticosteroid levels of pigs under commercial farm conditions. Journal of Veterinary Behavior 10(6), 569-576.

In intensive pig farming of Western and Southern Europe, welfare concerns are still often related to barren environments and crowded conditions. Pig producers need to balance the requirements to improve welfare conditions at farm with...

Anders, N., Roth, B., Grimsbø, E. et al. 2019. Assessing the effectiveness of an electrical stunning and chilling protocol for the slaughter of Atlantic mackerel (Scomber scombrus). PLOS ONE 14(9), e0222122.

Inducing unconsciousness in fish using electrical stunning prior to slaughter may improve fish welfare and fillet quality if such practises can be disseminated into wild capture fisheries. The objectives of this study were to: 1)...

Jung, L., Knierim, U. 2019. Differences between feather pecking and non-feather pecking laying hen flocks regarding their compliance with recommendations for the prevention of feather pecking – A matched concurrent case-control design. Applied Animal Behaviour Science 219, 104839.

Feather pecking (FP) is a multifactorial problem in all housing systems. Using a case-control design we wanted to determine a set of variables which may be decisive for a flock to become case or control...

Sanchez-Casanova, R., Sarmiento-Franco, L., Segura-Correa, J. et al. 2019. Effects of outdoor access and indoor stocking density on behaviour and stress in broilers in the subhumid tropics. Animals 9(12), 1016.

Studies investigating the welfare of commercial-line broiler chickens raised in houses with outdoor access in the tropics are scarce, and none have investigated whether responses vary according to indoor conditions. Hence, we assessed the effects...

Gibson, T., King, E., Spence, J. et al. 2019. Pathophysiology of concussive non-penetrative captive bolt stunning of turkeys. Animals 9(12), 1049.

The non-penetrative captive bolt (NPCB) has been proposed as a more humane and practical alternative to constant voltage electrical stunning for small-scale seasonal turkey producers. This study evaluated the effectiveness of the CASH® Small Animal...

Riddle, E. R., Ali, A. B. A., Campbell, D. L. M. et al. 2018. Space use by 4 strains of laying hens to perch, wing flap, dust bathe, stand and lie down. PLOS ONE 13(1), e0190532.

The laying hen industry is implementing aviary systems intended to improve welfare by providing hens with more space and resources to perform species-specific behaviors. To date, limited research has examined spatial requirements of various strains...

Santurtun, E., Broom, D. M., Phillips, C. J. C. 2018. A review of factors affecting the welfare of Atlantic salmon (Salmo salar). Animal Welfare 27(3), 193-204.

In the expanding salmon industry, many farmers use production methods that could result in poor welfare of the fish at various points of their lifecycle. We have reviewed methods used for producing salmon for food...

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...

Golledge, H., Carter, E. 2018. Welfare of fish farmed in the EU during transport and at slaughter. Animal Welfare 27(3), 287-288.

This Report, commissioned by the European Commission, summarises the current state of transport and slaughter practices in the aquaculture industry within eleven case-study countries in the European Economic Area (EAA). Comparisons are also made with...

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...

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)...

Woolcott, C., Torrey, S., Turner, P. et al. 2018. Evaluation of two models of non-penetrating captive bolt devices for on-farm euthanasia of turkeys. Animals 8(3), 42.

On-farm euthanasia is a critical welfare issue in the poultry industry and can be particularly difficult to perform on mature turkeys due to their size. We evaluated the efficacy of two commercially available non-penetrating captive...

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...