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. 
Meagher, R. K., Strazhnik, E., von Keyserlingk, M. et al. 2020. Assessing the motivation to learn in cattle. Scientific Reports 10, 6847.

Cognitive challenges may provide a form of enrichment to improve the welfare of captive animals. Primates, dolphins, and goats will voluntarily participate in learning tasks suggesting that these are rewarding, but little work has been...

Kneeland, M. R., Spagnuolo, V. A., Evers, D. C. et al. 2020. A novel method for captive rearing and translocation of juvenile common loons. Zoo Biology 39(4), 263–270.

Common loons (Gavia immer) are diving waterbirds that are particularly challenging to keep in captivity due to their specific behavioral and physiologic needs, special housing requirements, and susceptibility to stress‐related disease. We report a novel...

Brown, M. E., Torkelson, M. R., Olsen, G. H. et al. 2020. Comparison of fecal glucocorticoid metabolite concentrations in hand‐ versus parent‐reared whooping cranes (Grus americana). Zoo Biology 39(4), 276–280.

Endangered whooping cranes (Grus americana ) have been produced in captivity for reintroduction programs since the 1980s, using techniques such as artificial insemination, multiple clutching, and captive‐rearing to speed recovery efforts. Chicks are often hand‐reared...

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...

Williams, H. J., Duncan, J. S., Grove-White, D. H. et al. 2020. Repeatability and feasibility of pressure algometry for quantifying mechanical nociceptive threshold in the thoracic region of calves. Frontiers in Veterinary Science 7, 442.

Pressure algometry can be used to quantify mechanical nociceptive threshold (MNT) in humans and animals. If reliable this may be a useful tool to examine calves for increased mechanical sensitivity, which may be induced by...

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...

Smid, A. M. C., Weary, D. M., von Keyserlingk, M. A. G. 2020. The influence of different types of outdoor access on dairy cattle behavior. Frontiers in Veterinary Science 7, 257.

Pasture access for dairy cows is highly valued both by cows and the public at large. When pasture access is not feasible, farmers can provide cows with alternative forms of outdoor access, such as an...

Beck, M. R., Gregorini, P. 2020. How dietary diversity enhances hedonic and eudaimonic well-being in grazing ruminants. Frontiers in Veterinary Science 7, 191.

Ruminants evolved in diverse landscapes of which they utilized, by choice, a diverse arrangement of plants (grasses, forbs, and trees) for food. These plants provide them with both primary (carbohydrates, protein, etc.) and secondary (phenolics...

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...

Stracke, J., Klotz, D., Wohlsein, P. et al. 2020. Scratch the surface: Histopathology of foot-pad dermatitis in turkeys (Meleagris gallopavo). Animal Welfare 29(4), 419-432.

Foot-pad dermatitis (FPD) is an important indicator of animal welfare in turkeys (Meleagris gallopavo). The present study aimed to evaluate the reliability and validity of a commonly used five-point visual score (VC), assessing FPD based...

Augustin, A. J., Crabbs, M. A., Sour, M. C. et al. 2020. Efficient, effective, reusable, and customizable social housing for chickens in the laboratory. Laboratory Animal Science Professional 8(5) (September/October), 56-58.

The Iowa State University Laboratory Animal Resources Department needed caging specifically designed and purposed to socially house chickens in the laboratory. As indoor housing requests for chickens increased, the need for a dedicated caging system...

Szymczyk, K., Gabriel, S., Zegre Cannon, C. 2020. Removing the blindfold in blind intubation: A summary of tips and tricks for successful rabbit intubation. Laboratory Animal Science Professional 8(5) (September/October), 76-81.

Intubation in rabbits can be difficult due to their unique anatomical features. Large incisors, long narrow oral cavities, thick tongues, and limited mobility of the temporomandibular joint make laryngeal visualization difficult. It is the hope...

Worlds, T., Kearney, M., De La Garza, F. et al. 2020. Development of a rabbit enrichment program and contribution to a culture of transparency and care. Laboratory Animal Science Professional 8(6) (November/December), 38-40.

The Becton Dickinson (BD) Research Animal Care Program has developed an acclimation and enrichment program that has enhanced animal welfare for studies requiring single housing, contributed to a culture of care, increased transparency, and improved...

Acharya, R., Rault, J.-L. 2020. Risk factors for feather-damaging behavior in companion parrots: A social media study. Journal of Veterinary Behavior 40, 43-49.

Studies on the etiology of behavioral problems often involve interference in the animal's routine or reliance on owners' self-reports like surveys. Gathering data from videos posted on social media, a technique coined ‘video mining’, offers...

Bill, J., Rauterberg, S. L., Herbrandt, S. et al. 2020. Agonistic behavior and social hierarchy in female domestic rabbits kept in semi-groups. Journal of Veterinary Behavior 38, 21-31.

In semi-natural mixed-sex groups, rabbits (Oryctolagus cuniculus) organize their social life by forming a hierarchy, which is characterized by linearity and stability. Compared to the natural environment, many factors are different in contemporary breeding systems...

Chapa, J. M., Maschat, K., Iwersen, M. et al. 2020. Accelerometer systems as tools for health and welfare assessment in cattle and pigs – A review. Behavioural Processes 181, 104262.

Welfare assessment has traditionally been performed by direct observation by humans, providing information at only selected points in time. Recently, this assessment method has been questioned, as ‘Precision Livestock Farming’ technologies may be able to...

Gebhardt-Henrich, S. G., Jordan, A., Toscano, M. J. et al. 2020. The effect of perches and aviary tiers on the mating behaviour of two hybrids of broiler breeders. Applied Animal Behaviour Science 233, 105145.

Broiler breeders are kept for the production of fertile eggs. They face serious welfare problems like aggressive behaviour of the males towards females during mating. Furthermore, broiler breeders are usually kept without perches which are...

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...

Lange, A., Waiblinger, S., Heinke, A. et al. 2020. Gentle interactions with restrained and free-moving cows: Effects on the improvement of the animal-human relationship. PLOS ONE 15(11), e0242873.

The animal-human relationship is essential for farm animal welfare and production. Generally, gentle tactile and vocal interactions improve the animal-human relationship in cattle. However, cows that are fearful of humans avoid their close presence and...

Lecorps, B., Nogues, E., von Keyserlingk, M. A. G. et al. 2020. Pessimistic dairy calves are more vulnerable to pain-induced anhedonia. PLOS ONE 15(11), e0242100.

Pain induces deficits in appreciation of rewards (i.e. anhedonia) and variation in response to pain may be partly explained by individual differences in general expectations (i.e. optimism). Dairy calves are routinely subjected to painful procedures...

Liu, Z., Torrey, S., Newberry, R. C. et al. 2020. Play behaviour reduced by environmental enrichment in fast-growing broiler chickens. Applied Animal Behaviour Science 232, 105098.

The objective of this study was to evaluate effects of environmental enrichment on play behaviour in fast-growing broiler chickens. Chicks (19 of each sex) were randomly assigned to 6 non-enriched (NE) pens and 6 pens...

Meyer, M. M., Johnson, A. K., Bobeck, E. A. 2020. Development and validation of broiler welfare assessment methods for research and on-farm audits. Journal of Applied Animal Welfare Science 23(4), 433-446.

Required auditing of on-farm broiler welfare in the United States has increased; however, a lack of validated tools exists for assessment of enrichment. National Chicken Council (NCC) guidelines were used on a subset of 300...

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...

Munari, C., Ponzio, P., Macchi, E. et al. 2020. A multifactorial evaluation of different reproductive rhythms and housing systems for improving welfare in rabbit does. Applied Animal Behaviour Science 230, 105047.

The most widespread reproductive rhythm practiced in rabbit farming is based on artificial insemination (AI) performed at around 11 days pospartum. This approach results in high production rates, but requires high yearly replacement of animals...