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. 
Phillips, H. N., Heins, B. J. 2021. Effects of outdoor stocking density on growth, feather damage and behavior of slow-growing free-range broilers. Animals 11(3), 688.

Access to pasture is a main benefit of free-range broiler housing systems, yet the level of outdoor stocking density on broiler animal welfare remains unsettled. The growth, feather damage, pasture ranging and behaviors were assessed...

Bombail, V., Brown, S. M., Hammond, T. J. et al. 2021. Crying with laughter: Adapting the tickling protocol to address individual differences among rats in their response to playful handling. Frontiers in Veterinary Science 8, 677872.

In this Opinion paper, we consider whether current methods of tickling overemphasize the use of pinning (Figure 1) to which there may be a wider response variation than commonly acknowledged. We do not dispute that...

Learmonth, M. J., Sherwen, S., Hemsworth, P. 2021. Assessing choice ability and preferences of five Leopard Tortoises (Stigmochelys pardalis) for three stimuli through a novel two-phase preference test. Journal of Zoo and Aquarium Research, 9(2), 94-101.

Preference testing has long been used in ethology and animal welfare science to assess the preferences that animals have for different resources and stimuli. The study conducted herein assessed the choice-making ability of five leopard...

Learmonth, M. J., Sherwen, S., Hemsworth, P. H. 2021. Assessing preferences of two zoo-housed Aldabran giant tortoises (Aldabrachelys gigantea) for three stimuli using a novel preference test. Zoo Biology 40(2), 98-106.

Recent research has uncovered many complex cognitive traits and affective processes in many reptile species, such as the ability to make choices that are rewarding or pleasurable. The investigation herein was initiated after many years...

Anderson, M. G., Campbell, A. M., Crump, A. et al. 2021. Effect of environmental complexity and stocking density on fear and anxiety in broiler chickens. Animals 11(8), 2383.

Barren housing and high stocking densities may contribute to negative affective states in broiler chickens, reducing their welfare. We investigated the effects of environmental complexity and stocking density on broilers’ attention bias (measure of anxiety)...

Forslind, S., Blokhuis, H. J., Riber, A. B. 2021. Disturbance of resting behaviour of broilers under different environmental conditions. Applied Animal Behaviour Science 242, 105425.

Resting behaviours make up a large part of the daily time budget of broilers. However, in intensive broiler production systems disruptions of resting behaviours occur, where resting individuals get disturbed by active individuals. Such interruptions...

Edes, A. N., Baskir, E., Bauman, K. L. et al. 2021. Effects of crowd size, composition, and noise level on pool use in a mixed-species penguin colony. Animal Behavior and Cognition 8(4), 507–520.

Studies on how visitors affect penguins in human care report a mixture of negative, neutral, and positive impacts on behavior and physiology. Swimming is a highly motivated behavior that may promote positive welfare in penguins...

Ramont, M., Leahy, M., Cronin, K. A. 2021. Domestic animal welfare at the zoo: The impact of an animal visitor interaction program on chickens. Animal Behavior and Cognition 8(1), 1–14.

Many modern zoos strive to create connections between guests and animals through animal visitor interaction (AVI) programs. However, there has been relatively little research into the effect of AVI programs on the welfare of program...

Riley, A., Terry, M., Freeman, H. et al. 2021. Evaluating the effect of visitor presence on Nile crocodile (Crocodylus niloticus) behavior. Journal of Zoological and Botanical Gardens 2(1), 115–129.

Visitor presence has been shown to affect the behavior of animals in zoos. However, studies to date have not included a wide range of taxonomic groupings, and thus, the effect is poorly understood for many...

Wascher, C. A. F., Baur, N., Hengl, M. et al. 2021. Behavioral responses of captive corvids to the presence of visitors. Animal Behavior and Cognition 8(4), 481–492.

Behavioral responses of captive animals to the presence of visitors in zoos and wildlife parks can be interpreted as signs of negative (disturbance), neutral or positive (enrichment) welfare. In the present study, we investigated behavioral...

Muvhali, P. T., Bonato, M., Engelbrecht, A. et al. 2020. Extensive human presence and regular gentle handling improve growth, survival and immune competence in ostrich chicks. Journal of Applied Animal Welfare Science 23(1), 95-107.

A total of 416 day-old ostrich chicks were randomly allocated to one of the three different husbandry practices for 3 months after hatch; HP1 (extensive human presence with gentle human voice, visual and gentle physical...

Andreasen, S. N., Sandøe, P., Waiblinger, S. et al. 2020. Negative attitudes of Danish dairy farmers to their livestock correlates negatively with animal welfare. Animal Welfare 29(1), 89-98.

Positive stockperson attitudes to his or her animals is associated with a positive behavioural response in the animals and in other indicators assumed to reflect a high level of welfare as well as increased productivity...

Botman, J., Hontoir, F., Gustin, P. et al. 2020. Postanaesthetic effects of ketamine–midazolam and ketamine–medetomidine on gastrointestinal transit time in rabbits anaesthetised with isoflurane. Veterinary Record 186(8), 249.

Gastrointestinal stasis is a common perianaesthetic complication in rabbits. The objective of this study was to assess the impact on gastrointestinal transit time of ketamine–midazolam (KMZ) versus ketamine–medetomidine (later antagonised by atipamezole) (KMT-A) in rabbits...

Yaw, T. J., Mans, C., Johnson,S. et al. 2020. Evaluation of subcutaneous administration of alfaxalone-midazolam and dexmedetomidine-midazolam for sedation of ball pythons (Python regius). Journal of the American Veterinary Medical Association 256(5), 573-579.

OBJECTIVE: To evaluate SC administration of alfaxalone-midazolam and dexmedetomidine-midazolam for sedation of ball pythons (Python regius). ANIMALS: 12 healthy juvenile ball pythons. PROCEDURES: In a randomized crossover study, each snake was administered a combination of...

Costa, R., Leite Tamascia, M., Sanches, A. et al. 2020. Tactile stimulation of adult rats modulates hormonal responses, depression-like behaviors, and memory impairment induced by chronic mild stress: Role of angiotensin II. Behavioural Brain Research 379, 112250.

Physical touch can help to decrease the effects of stress. The aim of this study was to evaluate the influence of tactile stimulation on the hormonal and behavioral responses of young adult rats submitted to...

Alemán-Laporte, J., Bandini, L. A., Garcia-Gomes, M. S. et al. 2020. Combination of ketamine and xylazine with opioids and acepromazine in rats: Physiological changes and their analgesic effect analysed by ultrasonic vocalization. Laboratory Animals 54(2), 171–182.

In this study, the effect of four anaesthetic protocols that included the combination of xylazine (X) and ketamine (K) with acepromazine (A) and opioids (methadone (Me), morphine (Mo) or tramadol (T)) was evaluated in laboratory...

Ballantine, A., Rodgers, D., Watts, C. et al. 2020. The cotton rat – a new challenge. Animal Technology and Welfare 19(1), 92-95.

This poster describes how the Animal Technologists at Envigo adapted their current practices and procedures for a new species at their laboratory: the cotton rat. The paper describes cotton rat biology and behaviour; housing; environmental...

Rasys, A. M., Divers, S. J., Lauderdale, J. D. et al. 2020. A systematic study of injectable anesthetic agents in the brown anole lizard (Anolis sagrei). Laboratory Animals 54(3), 281–292.

Anolis lizards have served as important research models in fields ranging from evolution and ecology to physiology and biomechanics. However, anoles are also emerging as important models for studies of embryo development and tissue regeneration...

Okabe, S., Takayanagi, Y., Yoshida, M. et al. 2020. Gentle stroking stimuli induce affiliative responsiveness to humans in male rats. Scientific Reports 10, 9135.

Gentle tactile stimuli have been shown to play an important role in the establishment and maintenance of affiliative social interactions. Oxytocin has also been shown to have similar actions. We investigated the effects of gentle...

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...

Kane, L. P., Chinnadurai, S. K., Vivirito, K. et al. 2020. Comparison of isoflurane, sevoflurane, and desflurane as inhalant anesthetics in prairie rattlesnakes (Crotalus viridis). Journal of the American Veterinary Medical Association 257(9), 945-949.

OBJECTIVE: To characterize induction and recovery characteristics of 3 commonly used inhalant anesthetics in prairie rattlesnakes (Crotalus viridis): isoflurane, sevoflurane, and desflurane. ANIMALS: 12 healthy adult prairie rattlesnakes. PROCEDURES: In a randomized crossover design, snakes...

Kane, L. P., Chinnadurai, S. K., Vivirito, K. et al. 2020. Comparison of isoflurane, sevoflurane, and desflurane as inhalant anesthetics in prairie rattlesnakes (Crotalus viridis). Journal of the American Veterinary Medical Association 257(9), 945-949.

OBJECTIVE: To characterize induction and recovery characteristics of 3 commonly used inhalant anesthetics in prairie rattlesnakes (Crotalus viridis): isoflurane, sevoflurane, and desflurane. ANIMALS: 12 healthy adult prairie rattlesnakes. PROCEDURES: In a randomized crossover design, snakes...

LaFollette, M. R., Cloutier, S., Brady, C. M. et al. 2020. Changing human behavior to improve animal welfare: A longitudinal investigation of training laboratory animal personnel about heterospecific play or “rat tickling”. Animals 10(8), 1435.

Despite evidence for rat tickling’s animal welfare benefits, the technique is rarely implemented in part because of a lack of training. This study’s purpose was to determine the efficacy of online-only or online + hands-on...

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...

Rault, J.-L., Waiblinger, S., Boivin, X. et al. 2020. The power of a positive human–animal relationship for animal welfare. Frontiers in Veterinary Science 7, 590867.

Domestic animals often seek and enjoy interacting with humans. Positive human–animal relationships can elicit positive emotions and other positive welfare outcomes. Nevertheless, our understanding of the underlying processes that govern the positive perception of humans...