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. 
Pedersen, L. J., Herskin, M.S., Forkman, B. et al. 2014. How much is enough? The amount of straw necessary to satisfy pigs' need to perform exploratory behaviour. Applied Animal Behaviour Science 160, 46-55.

Since 10 years, EU-legislation states that "pigs must have permanent access to sufficient quantity of material to enable proper investigation and manipulation activities." While much research has focused on which materials enable proper investigation and...

Monts de Oca, N., Diaz, L., McMahen, D. et al. 2014. The use of lean management principles to enhance a nonhuman primate environmental enrichment program. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 580-581. (Abstract #P122).

Sewage back-up and overflows in the rooms of our primate facility initiated an analysis of the factors contributing to the clogging of the drains. An investigation reviewing the materials responsible for the clogging of the...

Rose, A. M., Ferrecchia, C. E., Van Andel, R. 2014. Developing an enrichment plan for water-regulated nonhuman primates. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 565 (Abstract #P60).

Environmental enrichment for nonhuman primates is an essential requirement in laboratory animal research. The Animal Welfare Regulations and the Guide for the Care and Use of Laboratory Animals state that the facility’s enrichment program must...

Willey, S. 2014. Nonhuman primate enrichment room planning, design, and use. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 539 (Abstract #PS52).

Princeton University continually makes efforts to improve and enhance the quality of life of our NHPs used in research. A part of this effort is to continue to improve our environmental enrichment program, promoting the...

Stevens, T. 2014. NHP wire biscuit feeder. Enrichment Record Dec 2, 2014 (online publication).

This apparatus is used for single-housed baboons of all ages. The device is a wire suet feeder used for birds and squirrels. It can be purchased from Walmart, Home Depot, etc. There are many sizes...

Qi, K., De-mi, S., Chuan, Q. 2014. Current understanding and use of environmental enrichment in China. Enrichment Record 20, 8-11.

In practice, consideration is given to providing most of the species used in research,testing and education withsome level of environmental enrichment. However, although the current level of awareness and understanding about the benefits of environmental...

Telkanranta, H., Bracke, M. B. M., Valros, A. 2014. Fresh wood reduces tail and ear biting and increases exploratory behaviour in finishing pigs. Applied Animal Behaviour Science 161, 51-59.

Chewing and rooting are high behavioural priorities in pigs. Lack of suitable materials can lead to abnormal behaviours such as tail and ear biting. In commercial farming, slatted floors limit the use of straw, and...

Croney, C. 2014. Let's stay together: Implications of social housing for laboratory pig welfare and management. Enrichment Record 19, 14-19.

Appropriately accommodating the pig's normal social behavior is an essential step in protecting its well-being in managed environments. Doing so is particularly important in laboratory settings in which distress due to social isolation and other...

Callan, T. 2014. Primates Presents. Enrichment Record 18, 5-6.

In the world of enrichment, ideas can be limitless. Sometimes, you just have to think outside the box... or in this case, "inside the box"! Who doesn't love a present with the colorful exterior and...

Alworth, L. C., Buerkle, S. C. 2013. The effects of music on animal physiology, behavior and welfare. Lab Animal 42(2), 54-61.

Physiological and psychological effects of listening to music have been documented in humans. The changes in physiology, cognition and brain chemistry and morphology induced by music have been studied in animal models, providing evidence that...

Reinhardt, V. (ed.) 2013. Compassion Makes a Difference - Discussions by the Laboratory Animal Refinement & Enrichment Forum [LAREF], Volume III. Animal Welfare Institute, Washington, DC.

This is the third volume of discussions that took place on the Laboratory Animal Refinement & Enrichment Forum (LAREF). This forum is dedicated to the exchange of personal experiences of refining the conditions under which...

Pierre, P. J., Torres, N. A., Rosga, M. D. et al. 2013. Colony-wide assessment of the foraging devices: Refinement of delivery practices, cost and the caloric content delivered via foraging devices. American Journal of Primatology 75(S1), 82. (36th Meeting of the American Society of Primatologists Scientific Program, Abstract #163)

Foraging opportunities are a key component of enrichment in captive nonhuman primates (NHP) providing manipulative opportunities in which animals can engage in species-typical behaviors. Recent studies suggest captive NHP populations have increased body weight over...

DeBoer, S. P., Garner, J. P., Lay Jr, D. C. et al. 2013. Does the presence of a human affect the preference of enrichment items in young, isolated pigs? Applied Animal Behaviour Science 143(2-4), 96-103.

Pigs may be housed individually in both production and research settings. Gregarious by nature, pigs kept in isolation may show behavioural and physiological signs of stress. In this study we investigated the preference of individually...

Hrapkiewicz, K., Colby, L. A., Denison, P. 2013. Clinical Laboratory Animal Medicine: An Introduction (4th Ed). Wiley-Blackwell, Ames, IA.

Clinical Laboratory Animal Medicine: An Introduction, Fourth Edition offers a user-friendly guide to the unique anatomy and physiology, care, common diseases, and treatment of small mammals and nonhuman primates. Carefully designed for ease of use...

Hoffman, H. 2013. Ice cube treats for swine. Enrichment Record 16, 23-24.

The frozen Veggie Bite ice cube treat is hung inside the swine chain-link type enclosure with a Carabineer hook. ... Because swine avoid objects that are contaminated with feces, suspending this enrichment treat encourages more...

Gehlot, P. 2013. Enrichment of Göttingen Minipigs: Models of human hepatocellular carcinoma. Newsletter Ellegaard 40, 4-5.

Social or pair-housing is our main form of swine enrichment. The minipigs are group-housed in stalls that have sliding divider doors/panel which allow separation of animals for feeding and study procedures, as needed. Ideally, enrichment...

Zebunke, M., Puppe, B., Langbein, J. 2013. Effects of cognitive enrichment on behavioural and physiological reactions of pigs. Physiology & Behavior 118, 70-79.

Cognitive enrichment, a special form of environmental enrichment, addresses the cognitive abilities of animals in captivity. Through cognitive interaction with the environment, the animals regain a certain control over their environment, and essential resources, such...

Olivo, D. 2012. The benefits of adding a little color to a monkey's environment. Enrichment Record 10, 7.

Imagine if your everyday world was boring, blah and completely sterile looking with limited amounts of color. Unimaginable, right? Here at Legacy Schering Plough/Merck, we thought the same about our nonhuman primates who look at...

Froberg-Fejko, K. M., Lecker, J. L. 2012. Going back to nature: The benefits of wood enrichment. Lab Animal 41(11), 345-347.

Environmental enrichment can be defined as altering the living environment of captive animals in order to provide them with opportunities to express more of their natural behavioral repertoire. The challenge of providing effective enrichment in...

Toenepoehl, B., Appel, A. K., Welp, S. et al. 2012. Effect of marginal environmental and social enrichment during rearing on pigs' reactions to novelty, conspecifics and handling. Applied Animal Behaviour Science 140(3-4), 137-145.

The rearing environment of farmed animals can affect their behaviour when handled, and therefore needs to be taken into account when selecting for traits such as docility. Therefore, 126 German Landrace and Pietrain × German...

Luchins, K. R., Baker, K. C., Gilbert, M. H. et al. 2011. Manzanita wood: A sanitizable enrichment option for nonhuman primates. JAALAS 50(6), 884-887.

Wooden objects are often used as nonhuman primate enrichment to provide variety and novelty, promote exploratory behavior, and supply an outlet for curiosity. However, concerns have been raised regarding the ability to sanitize wood by...

Wood, L. L., Boyd, A. M., Rose, R. et al. 2011. Implementation of an enrichment rack for singly housed male nonhuman primates. American Association for Laboratory Animal Science [AALAS] Meeting Official Program, 732 (Abstract #PS54).

The racks provide four different levels of horizontal bars where manipulanda can be hung. .. The racks are positioned in front of a 4-caged housing system. .. The enrichment racks have produced an increase in...

Huber, H. F., Lewis, K. P. 2011. An assessment of gum-based environmental enrichment for captive gummivorous primates. Zoo Biology 30(1), 71-78.

In the wild, many primates consume gums exuded from trees, and many species are gum specialists. In spite of this, few data exist concerning gum feeding in captivity. Using a web-based survey of 46 zoos...

Van de Perre, V., Driessen, B., Van Thielen, J. et al. 2011. Comparison of pig behaviour when given a sequence of enrichment objects or a chain continuously. Animal Welfare 20(4), 641-649.

Tail biting is a major problem in modern pig (Sus scrofa) production and results in a reduction of animal welfare and productive performance. Biting behaviour has been shown to be decreased by the use of...

Oostindjer, M., van den Brand, H., Kemp, B. et al. 2011. Effects of environmental enrichment and loose housing of lactating sows on piglet behaviour before and after weaning. Applied Animal Behaviour Science 134(1-2), 31-41 .

Weaning of piglets in commercial husbandry systems is earlier and more abrupt than would happen under natural conditions, resulting in low feed intakes and health and welfare problems in the immediate postweaning period. Piglets in...