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. 
Stuckey, J. E., Makhija, S. D., Reimer, D. C. et al. 2023. Effects of different grades of carbon dioxide on euthanasia of mice (Mus musculus). JAALAS 62(5), 430–437.

Carbon dioxide (CO2) is a conditionally acceptable method for mouse euthanasia, according to the American Veterinary Medical Association Guidelines for the Euthanasia of Animals. In a 2012 Office of Laboratory Animal Welfare (OLAW) webinar, representatives...

Tirado-Muñiz, N., Spangler, T. L., Van Rooyen, H. et al. 2023. Evaluation of cage mate–induced postsurgical trauma in mice. JAALAS 62(2), 170–178.

Although mice are social animals, individual housing is sometimes requested after surgery. We questioned whether pair-housing mice after surgery resulted in greater trauma to the surgical site as compared with single housing. We further evaluated...

Yang, P., Hish, G., Lester, P. A. 2023. Comparison of systemic extended-release buprenorphine and local extended-release bupivacaine-meloxicam as analgesics for laparotomy in mice. JAALAS 62(5), 416–422.

Extended-release (ER) local anesthetics can be used in multi-modal analgesia or in situations in which systemic analgesics may alter animal physiology and thus introduce interpretational confounds. In this study, we compared the analgesic efficacy of...

Yoshida, K. 2023. Comparison of low and high doses of pentobarbital or thiopental for euthanasia of isoflurane-anesthetized pigs. JAALAS 62(2), 185–188.

Barbiturate overdose is a common method for euthanizing pigs. However, barbiturates can cause tissue damage and may affect experimental results, so the minimal dose should be used. The minimal dose of barbiturate for euthanasia in...

Paul, E. S., Browne, W., Mendl, M. T. et al. 2022. Assessing animal welfare: A triangulation of preference, judgement bias and other candidate welfare indicators. Animal Behaviour 186, 151-177.

To assess the welfare of captive animals, validated measures, so-called ‘welfare indicators’, are required. We used a triangulation approach to investigate the extent to which different measures converged to provide corroborating evidence of welfare. Laying...

Brereton, J., Rose, P. 2022. An evaluation of the role of 'biological evidence' in zoo and aquarium enrichment practices. Animal Welfare 31(1), 13-26.

Evidence-based approaches are key to advancing all areas of zoo and aquarium practice. Output from empirical study must be disseminated to those within the industry so that results can support changes to husbandry and management...

Tillmanns, M., Scheepens, K., Stolte, M. et al. 2022. Implementation of a pig toilet in a nursery pen with a straw-littered lying area. Animals 12(1), 113.

In this study, a pig toilet was installed on an organic pig farm, which enabled pigs to use a lying area littered with straw and keep it clean. The pig toilet was separated into a...

Sundman, E. R., Gabler, N. K., Millman, S. T. et al. 2022. The use of attractants to stimulate neonatal piglet interest in rope enrichment. Animals 12(2), 211.

In the United States swine industry, preweaning mortality represents the highest mortality rate of any production phase, nearly half attributed to crushing. The overarching aim of this study was to determine if enrichment ropes would...

Götz, S., Raoult, C. M. C., Reiter, K. et al. 2022. Lying, feeding and activity preference of weaned piglets for LED-illuminated vs. dark pen compartments. Animals 12(2), 202.

Little is known on the effect of light on pig behaviour. The choice behaviour of weaned piglets kept under two different light-emitting diode (LED) illuminance levels was investigated: 32 piglets (in two batches) were housed...

Blenkuš, U., Gerós, A. F., Carpinteiro, C. et al. 2022. Non-invasive assessment of mild stress-induced hyperthermia by infrared thermography in laboratory mice. Animals 12(2), 177.

Stress-induced hyperthermia (SIH) is a physiological response to acute stressors in mammals, shown as an increase in core body temperature, with redirection of blood flow from the periphery to vital organs. Typical temperature assessment methods...

Rana, M. S., Lee, C., Lea, J. M. et al. 2022. Commercial free-range laying hens’ preferences for shelters with different sunlight filtering percentages. Animals 12(3), 344.

Extreme sunlight might be aversive to free-range laying hens, discouraging them from going outside. Range enrichment with artificial shelters may protect hens from sunlight and increase range use. The preferences of 34–40-week-old Hy-Line Brown laying...

Taylor, P. S., Hemsworth, P. H., Rault, J.-L. 2022. Environmental complexity: Additional human visual contact reduced meat chickens’ fear of humans and physical items altered pecking behavior. Animals 12(3), 310.

Increased environmental complexity can improve animal welfare, depending on the resources provided and use by the animal. We provided chickens either with physical items that posed no biosecurity risk and were inexpensive (balls, chains, perches...

Campbell, D. L. M., Belson, S., Dyall, T. R. et al. 2022. Impacts of rearing enrichments on pullets’ and free-range hens’ positive behaviors across the flock cycle. Animals 12(3), 280.

Enrichment during the indoor rearing of pullets destined for free-range systems may optimize pullet development including increasing motivated natural behaviors (termed ‘positive behaviors’) including foraging, dust bathing and chick play. Hy-Line Brown® chicks (n =...

Acharya, R. Y., Hemsworth, P. H., Coleman, G. J. et al. 2022. The animal-human interface in farm animal production: Animal fear, stress, reproduction and welfare. Animals 12(4), 487.

A negative human-animal relationship (HAR) from the perspective of the animal is a limiting factor affecting farm animal welfare, as well as farm animal productivity. Research in farm animals has elucidated sequential relationships between stockperson...

Ratuski, A. S., Weary, D. M. 2022. Environmental enrichment for rats and mice housed in laboratories: A metareview. Animals 12(4), 414.

Environmental enrichment has been widely studied in rodents, but there is no consensus on what enrichment should look like or what it should achieve. Inconsistent use of the term “enrichment” creates challenges in drawing conclusions...

Rowe, E., Mullan, S. 2022. Advancing a “good life” for farm animals: Development of resource tier frameworks for on-farm assessment of positive welfare for beef cattle, broiler chicken and pigs. Animals 12(5), 565.

There is increasing recognition that farm animal welfare standards should ensure positive welfare, as well as prevent negative welfare. Resources that are valued by an animal and that provide opportunities to engage in motivated behaviours...

Mocz, F., Michel, V., Janvrot, M. et al. 2022. Positive effects of elevated platforms and straw bales on the welfare of fast-growing broiler chickens reared at two different stocking densities. Animals 12(5), 542.

In conventional rearing systems, fast-growing broiler chickens commonly experience welfare issues, such as contact dermatitis, walking difficulties or a lack of expression of species-specific behaviours. Enriching their environment may be a way to improve their...

Baker, P. E., Nicol, C. J., Weeks, C. A. 2022. The effect of hard pecking enrichment during rear on feather cover, feather pecking behaviour and beak length in beak-trimmed and intact-beak laying hen pullets. Animals 12(6), 674.

Injurious pecking, commonly controlled by beak trimming (BT), is a widespread issue in laying hens associated with thwarted foraging. This controlled study compared the effect in intact and beak-trimmed pullets of providing pecking pans to...

Kieffer, J. D., Campler, M. R., Cheng, T.-Y. et al. 2022. Evaluation of a water-based medium-expansion foam depopulation method in suckling and finisher pigs. Animals 12(8), 1041.

The threat of foreign animal disease introduction through contaminated animal products, feed ingredients, and wildlife vectors have highlighted the need for additional approved methods for mass depopulation of swine under emergency scenarios, especially methods that...

Sandilands, V., Baker, L., Donbavand, J. et al. 2022. Do hens use enrichments provided in free-range systems? Animals 12(8), 995.

Hens in free-range systems are given enrichments to increase foraging and limit injurious pecking, but the efficacy of enrichment types requires investigation. We studied hen behaviour and feather cover in eight commercial free-range flocks each...

Pritchett, R. K., Gaskill, B. N., Erasmus, M. A. et al. 2022. Scratch that itch: Farrowing crate scratching enrichment for sows. Animal Welfare 31(2), 243-255.

Developing effective enrichments is important for improving pig (Sus scrofa) welfare as it increases species-specific behaviours, decreases abnormal behaviours, and increases time active. However, few enrichments are available for sows in farrowing crates. Pigs are...

Reynolds, P. S. 2022. Introducing non-aversive mouse handling with ‘squnnels’ in a mouse breeding facility. Animal Technology and Welfare 21(1), 42-45.

Based on queries received during our 2021 LASA 3Rs’ presentation, we describe operational highlights and concerns that came up during the rollout of nonaversive handling as standard of care at our mouse breeding facility. We...

Zeltner, A., Cristofferson, C. 2022. Taking blood from a Göttingen minipig while placed in a sling. Animal Technology and Welfare 21(1), 58-61.

Traditionally Göttingen minipigs are restrained in dorsal recumbency to have access to the blood vessels in the neck. Minipigs, like any other animal do not particularly like to be restrained and being turned on their...

Davis, H. J., Barabas, A. J., Gaskill, B. N. 2022. Titrating the preferences of altered lighting against temperature in female CD-1 laboratory mice, Mus musculus. Applied Animal Behaviour Science 246, 105541.

Aspects of the laboratory are aversive to mice, such as being housed under bright lights and at temperatures below their thermal comfort, causing stress and poor welfare. While murine thermal preferences are well understood, light...

Kitchenham, L., Nazal, B., Adcock, A. et al. 2022. Why does lifelong conventional housing reduce the sociability of female mice? Applied Animal Behaviour Science 246, 105532.

Compared to peers raised in well-resourced, 'enriched' environments (‘EE’), female laboratory mice from conventional barren cages are more aggressive to their cage-mates, and less sociable with familiar non-cage-mates (especially if these too are from conventional...