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. 
Sobotik, E. B., Nelson, J. R., Archer, G. S. 2020. How does ultraviolet light affect layer production, fear, and stress. Applied Animal Behaviour Science 223, 104926.

The lighting spectrum used in modern poultry production commonly lacks significant amounts of ultraviolet light; however, poultry can perceive the ultraviolet spectrum unlike humans and little research has been done to investigate the importance of...

Arrazola, A., Mosco, E., Widowski, T. M. et al. 2020. The effect of alternative feeding strategies during rearing on the behaviour of broiler breeder pullets. Applied Animal Behaviour Science 224, 104929.

Broiler breeders are feed-restricted during rearing to avoid the negative consequences of obesity during lay due to their genetic potential for fast growth rate. Feed restriction leads to chronic hunger, frustration and lack of satiety...

Baxter, M., Richmond, A., Lavery, U. et al. 2020. Investigating optimal levels of platform perch provision for windowed broiler housing. Applied Animal Behaviour Science 225, 104967.

Broiler chickens show a preference for platform perches over traditional bar perches. Further information is needed on the optimal provision of these perches in order for them to be successfully installed in commercial systems. This...

Li, G., Li, B., Shi, Z. et al. 2020. Diurnal rhythms of group-housed layer pullets with free choices between light and dim environments. Canadian Journal of Animal Science 100(1), 37-46.

Chickens under appropriate light–dark programs can develop diurnal rhythms. However, actual needs of layer pullets for the light and dark environments are not fully understood. This study was to investigate the diurnal rhythms of pullets...

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...

Ross, S. R., Leinwand, J. G. 2020. A review of research in primate sanctuaries. Biology Letters 16(4), 1620200033.

While non-human primate studies have long been conducted in laboratories, and more recently at zoological parks, sanctuaries are increasingly considered a viable setting for research. Accredited sanctuaries in non-range countries house thousands of primates formerly...

MacAllister, R. P., Heagerty, A., Coleman, K. 2020. Behavioral predictors of pairing success in rhesus macaques (Macaca mulatta). American Journal of Primatology 82(1), e23081.

Pair housing is one of the most important components of behavioral management for caged macaques; however, it can result in aggression and injury if partners are incompatible. Knowing when to proceed and when to stop...

Overduin-de Vries, A. M., de Vries, H., Vermande, M. M. et al. 2020. Both aggressive and affiliative behaviour facilitate resource access in high-ranking female long-tailed macaques (Macaca fascicularis). Behaviour 157 (3-4), 267-287.

Access to limited resources may be achieved by dominance as well as by high rates of aggressive and affiliative behaviour. We investigated the relative effectiveness of dominance rank and aggressive and affiliative behaviour in accessing...

Skalníková, P., Frynta, D., Abramjan, A. et al. 2020. Spontaneous color preferences in rhesus monkeys: What is the advantage of primate trichromacy? Behavioural Processes 174, 104084.

Color perception and color signaling play an important role in various aspects of animal behavior. However, in mammals, trichromatic vision characterized by three retinal photopigments tuned to peak short, middle and long wavelengths is limited...

Bertho, J.-M., Ancelet, S., Denais-Laliève, D. et al. 2020. Humane endpoints in severe irradiation experiments using non-human primates: A retrospective analysis. Scandinavian Journal of Laboratory Animal Science 46(1).

A retrospective statistical study has been performed in order to identify the biological, clinical and behavioural variables that could potentially predict the survival status of irradiated non-human primates (NHP) and to refine the future use...

Ebel, S. J., Kopp, K. S., Liebal, K. 2020. Object preferences in captive Sumatran orang-utans (Pongo abelii). Behavioural Processes 170, 103993.

While preferences for perceptual features of objects are well studied in humans, little is known about this trait in other great apes. We therefore presented captive Sumatran orang-utans (Pongo abelii) with objects that differed in...

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...

Johnston, J. R., Meeker, T. L., Ramsey, J. K. et al. 2020. Utility of automated feeding data to detect social instability in a captive breeding colony of rhesus macaques (Macaca mulatta): A case study of intrafamily aggression. JAALAS 59(1), 46–57.

Some captive breeding colonies of rhesus macaques live in large outdoor multimale, multifemale social groups. These groups are composed of several matrilineal families, governed by a clear female dominance hierarchy. Aggression within the same or...

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...

Sharpe, S. A., Scott, S., Taylor, I. et al. 2020. Use of high frequency jet ventilation as a refinement for imaging macaques with respiratory disease. Laboratory Animals 54(4), 386–390.

Imaging is used in human medicine to diagnose disease and monitor treatment efficacy. Computed tomography (CT) positron emission tomography (PET) and magnetic resonance (MR) are applied to animal models of infectious diseases to increase data...

Mishra, P. S., Pal, A., Velankar, A. D. et al. 2020. Does rank rule? Rank-related grooming patterns in Nicobar long-tailed macaques Macaca fascicularis umbrosus. Primates 61(3), 443–453.

Primates maintain social bonds with specific individuals in the group by directing grooming toward them. Social grooming is often targeted toward individuals with whom the most benefits can be exchanged, which are usually the high-ranking...

Stocker, M. Loretto, M.-C., Sterck, E. H. M. et al. 2020. Cooperation with closely bonded individuals reduces cortisol levels in long-tailed macaques. Royal Society Open Science 7(5), 7191056.

Many animal species cooperate with conspecifics in various social contexts. While ultimate causes of cooperation are being studied extensively, its proximate causes, particularly endocrine mechanisms, have received comparatively little attention. Here, we present a study...

Bari, M. S., Downing, J. A., Dyall, T. R. et al. 2020. Relationships between rearing enrichments, range use, and an environmental stressor for free-range laying hen welfare. Frontiers in Veterinary Science 7, 480.

Enrichments during pullet rearing may improve adaptation and welfare of hens as they move from indoor rearing to a free-range system. Individual variation in outdoor ranging may also affect welfare. This study assessed the effects...

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...

Reinhardt, V. (ed.) 2020. It’s Okay to Cry - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume V. Animal Welfare Institute, Washington, DC.

This is the 5th volume of selected discussions that took place on the electronic Laboratory Animal Refinement & Enrichment Forum between February 2016 and December 2019. The forum was created in October 2002; it allows...