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. 
Thøfner, I., Hougen, H. P., Villa, C. et al. 2020. Pathological characterization of keel bone fractures in laying hens does not support external trauma as the underlying cause. PLOS ONE 15(3), e0229735.

Keel bone fractures in laying hens have been described with increasing prevalence from several countries over the last twenty years and are considered one of the greatest welfare problems to the layer industry. In Denmark...

Armstrong, E. A., Rufener, C., Toscano, M. J. et al. 2020. Keel bone fractures induce a depressive-like state in laying hens. Scientific Reports 10(1), 3007.

In commercial flocks of laying hens, keel bone fractures (KBFs) are prevalent and associated with behavioural indicators of pain. However, whether their impact is severe enough to induce a depressive-like state of chronic stress is...

Składanowska-Baryza, J., Ludwiczak, A., Pruszyńska-Oszmałek, E. et al. 2020. Effect of two different stunning methods on the quality traits of rabbit meat. Animals 10(4), 700.

The aim of the study was to assess the effect of two different stunning methods on the level of blood stress indicators (cortisol, insulin, glucose) and rabbit meat quality. The experiment was conducted on crossbreds...

Trocino, A., White, P., Bordignon, F. et al. 2020. Effect of feed restriction on the behaviour and welfare of broiler chickens. Animals 10(5), 830.

Under intensive rearing conditions, the welfare of broiler chickens may be at risk depending on genotype and sex, due to their different growth rates. The practice of quantitative feed restriction may also impact on welfare...

Spindler, B., Weseloh, T., Eßer, C. et al. 2020. The effects of UV-A light provided in addition to standard lighting on plumage condition in laying hens. Animals 10(6), 1106.

Natural light with ultraviolet spectrum (UV) influences the birds´ perception, the reflectivity of their plumage and affects bird behavior. Therefore, in Germany, laying hens kept in barns should be provided with daylight inlets. Nevertheless, lighting...

Monckton, V., van Staaveren, N., Harlander-Matauschek, A. 2020. Broiler chicks’ motivation for different wood beddings and amounts of soiling. Animals 10(6), 1039.

In the wild, excreta soiled surroundings can attract predators and spread disease. Yet, farmers rear broiler chicks in large barns with stocking densities that prevent excreta segregation. To measure chicks’ motivation to access unsoiled bedding...

Tahamtani, F. M., Riber, A. B. 2020. The effect of qualitative feed restriction in broiler breeder pullets on fear and motivation to explore, Applied Animal Behaviour Science 228, 105009.

Restrictively fed broiler breeders are known to have increased motivation to explore and reduced fearfulness because hunger increases the motivation to search for and to acquire food, forcing the birds to face and engage with...

Soliman, F. N. K., El-Sabrout, K. 2020. Light wavelengths/colors: Future prospects for broiler behavior and production. Journal of Veterinary Behavior 36, 34-39.

Assessing animal welfare is necessary from animal behavior and product quality/quantity perspectives. Birds have a unique visual system and see in the range of 315-750 nm. Most of their behavior is mediated by vision. Lighting...

Wang, R., Liu, R., Li, L. et al. 2020. Fasting is not required for measuring plasma lipid levels in rabbits. Laboratory Animals 54(3), 272–280.

Plasma lipid and glucose levels are important parameters for evaluating the onset and development of metabolic and cardiovascular diseases. In clinical and experimental studies of humans or mice, fasting is often required before testing plasma...

Tahamtani, F. M., Moradi, H., Riber, A. B. 2020. Effect of qualitative feed restriction in broiler breeder pullets on stress and clinical welfare indicators. Frontiers in Veterinary Science 7, 316.

The feed restriction applied during rearing of broiler breeders inflicts chronic hunger, and frustration due to unfulfilled behavioural needs for feeding. To alleviate the welfare problems associated with feed restriction, qualitative feed restriction allows a...

Nordquist, R. E., Zeinstra, E. C., Dougherty, A. et al. 2020. Effects of dark brooder rearing and age on hypothalamic vasotocin and feather corticosterone levels in laying hens. Frontiers in Veterinary Science 7, 19.

Chickens cannot independently thermoregulate at hatch and lack opportunity to behaviorally thermoregulate with a hen in the egg layer industry, thus barns are heated to thermoneutral temperatures. Dark brooders are low-energy-consuming hot plates, which may...

Ipema, A. F., Gerrits, W. J. J., Bokkers, E. A. M. et al. 2020. Provisioning of live black soldier fly larvae (Hermetia illucens) benefits broiler activity and leg health in a frequency- and dose-dependent manner. Applied Animal Behaviour Science 230, 105082.

Fast-growing broilers spend most their time inactive and are therefore prone to experience leg problems. Environmental enrichment that facilitates intrinsically motivated behaviours can potentially promote activity and reduce leg problems, thereby improving broiler welfare. A...

Moroki, Y. 2020. Impact of flooring type on the sham dustbathing behaviour of caged laying hens. Applied Animal Behaviour Science 230, 105066.

Feed particles are preferred for foraging and they are also a stimulus for sham dustbathing. Most sham dustbathing bouts start with bill raking in the feed by caged hens. As hens often exhibit a floor...

Gent, T. C., Gebhardt-Henrich, S., Schild, S.-L. A. et al. 2020. Evaluation of poultry stunning with low atmospheric pressure, carbon dioxide or nitrogen using a single aversion testing paradigm. Animals 10(8), 1308.

Low atmospheric pressure stunning (LAPS) has been suggested for use in poultry under 4 kg in the abattoir as a more humane alternative to carbon dioxide (CO2). However, there are currently no studies offering a...

Jung, L., Brenninkmeyer, C., Niebuhr, K. et al. 2020. Husbandry conditions and welfare outcomes in organic egg production in eight European countries. Animals 10(11), 2102.

In the European research project HealthyHens, welfare indicators as well as husbandry and management conditions were recorded in 107 organic laying hen farms in eight countries. Farms were visited at peak and end of lay...

McMahon, S. A., Wigham, E. 2020. ‘All Ears’: A questionnaire of 1516 owner perceptions of the mental abilities of pet rabbits, subsequent resource provision, and the effect on welfare. Animals 10(10), 1730.

Pet rabbit welfare is a hidden crisis: Inappropriately housed, fed, and not routinely provided healthcare—rabbits can often suffer painful conditions and shortened lifespans. This study provides novel understanding of owners’ perceptions of rabbits’ mental capabilities...

Monckton, V., Ellis, J. L., Harlander-Matauschek, A. 2020. Floor substrate preferences of chickens: A meta-analysis. Frontiers in Veterinary Science 7, 584162.

Environmental enrichment promotes sensory and motor stimulation for species-typical behaviors, which in turn enhance animal well-being. For farmed Galliformes, housing systems often limit enrichment to bedding and litter, that simultaneously act as material for dustbathing...

Rokavec, N., Zupan Šemrov, M. 2020. Psychological and physiological stress in hens with bone damage. Frontiers in Veterinary Science 7, 589274.

Abnormalities in bone development in humans and non-humans can lead to impaired physical and psychological health; however, evidence is lacking regarding the role of individual psychosocial factors in the development of poor bone conditions. Addressing...

Rufener, C., Rentsch, A. K., Stratmann, A. et al. 2020. Perch positioning affects both laying hen locomotion and forces experienced at the keel. Animals 10(7), 1223.

The aim of this study was to assess the effect of perch positioning on laying hens’ locomotion and the resulting energy experienced at the keel. Twenty Nick Chick and 20 Brown Nick hens were trained...

Nawroth, C., Gygax, L. 2020. The legislative, ethical, and conceptual importance of replicability in farm animal welfare science. agriRxiv 2020, 20203211980.

In this commentary, we discuss three replicability issues that are specifically relevant to research regarding farm animal welfare: (1) Legislative action, and its potential economic consequences, should derive from robust and replicable research to benefit...

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...

Decina, C., Berke, O., van Staaveren, N. et al. 2019. An investigation of associations between management and feather damage in Canadian laying hens housed in furnished cages. Animals 9(4), 135.

Feather pecking is a continuous welfare challenge in the housing of egg-laying hens. Canada is currently making the transition from conventional cages to alternative housing systems. However, feather damage (FD) among laying hens due to...

Bill, J., Rauterberg, S. L., Stracke, J. et al. 2019. Prevalence and severity of tail lesions as a possible welfare indicator for rabbit does. Animal Welfare 28(4), 511-518.

The impact of behavioural disorders on animal welfare in modern animal husbandry has been much debated. While other abnormal behaviours have been explored at length, there are a paucity of studies on tail-biting in rabbits...

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...