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. 
Lambert, H., Cornish, A., Waley, D. 2024. The value of regulating stocking densities in aquaculture must not be dismissed: A reply to Saraiva et al. 2022. Frontiers in Veterinary Science 10.

We would like to rebut the argument made by Saraiva et al. (1) in their paper “Finding the “golden stocking density”: a balance between fish welfare and farmers' perspectives,” that stocking densities should not be...

Robinson, L. M., Weiss, A. (Eds.) 2023. Nonhuman Primate Welfare: From History, Science, and Ethics to Practice. Springer, Cham, Switzerland. 671 p.

This volume reviews the broad topic of welfare in nonhuman primates under human care. Chapters detail the history of primates in captivity, ethical and legal issues surrounding the use of nonhuman primates as entertainment or...

Evans, L., Brooks, G. C., Anderson, M. G. et al. 2023. Environmental complexity and reduced stocking density promote positive behavioral outcomes in broiler chickens. Animals 13(13), 2074.

The objective was to evaluate the impacts of a complex environment and stocking density on Ross 708 broiler chicken behaviors. Eight pens contained either high complexity (HC) or low complexity (LC) environments, and high (HD)...

Chakravarty, S., Donoghue, J., Waite, A. S. et al. 2023. Closed-loop control of anesthetic state in nonhuman primates. PNAS Nexus 2(10), 293.

Research in human volunteers and surgical patients has shown that unconsciousness under general anesthesia can be reliably tracked using real-time electroencephalogram processing. Hence, a closed-loop anesthesia delivery (CLAD) system that maintains precisely specified levels of...

Ruíz-López, P., Cuypers, C., Schauvliege, S. 2023. Xylazine infusion during equine colic anesthesia with isoflurane and lidocaine: A retrospective study. Animals 13(18), 2902.

This retrospective study investigated the effect of a xylazine infusion on heart rate; mean arterial pressure; blood gases; anesthetic and dobutamine requirements; recovery quality and duration; percentage of death/survival; and days to die/discharge in horses...

Hanh, H. Q., Phuong, N. T., Tien, N. D. et al. 2023. Effects of stocking density in group cages on egg production, profitability, and aggressive pecking of hens. Journal of Applied Animal Welfare Science 26(3), 374–385.

There is an increasing concern about welfare issues related to battery cages, which are commonly used in Vietnam, and requires a modified cage that improves hen welfare while retaining its economic and management advantages. We...

Vidament, M., Bonneau, C., Lansade, L. 2023. Personality of equids: Donkeys and draught horses behave differently in fear and tactile sensitivity tests. Applied Animal Behaviour Science 269, 106113.

Horses and donkeys are used for agriculture, leisure, urban services and therapy. Although these two species obviously behave differently, it is important to measure their behavioural specificity when tested in the same situations and to...

Webb, J. K., Keller, K. A., Chinnadurai, S. K. et al. 2023. Use of alfaxalone in bearded dragons (Pogona vitticeps): Optimizing pharmacodynamics and evaluating cardiogenic effects via echocardiography. Journal of the American Veterinary Medical Association 261(1), 126–131.

OBJECTIVE Bearded dragons (Pogona vitticeps), a popular zoological companion species, frequently require sedation for procedures. A novel formulation of alfaxalone with preservatives was FDA approved for 28-day use after the vial is breached. Research has...

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...

Guerrero-Martin, S. M., Brill, S., Carlson, B. W. 2022. Development and implementation of a positive reinforcement training program for nonhuman primates in biomedical research. Laboratory Animal Science Professional 10(1) (January/February), 48-52.

Despite clear benefits of PRT for NHPs and biomedical research, investigators often view the investment in personnel expertise and time required to train animals as deterrents towards adopting PRT. We provide an example of how...

Torcivia, C., McDonnell, S. 2022. Efficacy of lidocaine topical solution in reducing discomfort reaction of horses to intramuscular vaccination. Animals 12(13), 1659.

Vaccinations via intramuscular injection are a key component of preventative health care in horses. Development of problematic behavioral aversion to injections is quite common. Our clinical impression has been that topical anesthetic applied to injection...

Prentice, P. M., Houslay, T. M., Wilson, A. J. 2022. Exploiting animal personality to reduce chronic stress in captive fish populations. Frontiers in Veterinary Science 9, 1046205.

Chronic stress is a major source of welfare problems in many captive populations, including fishes. While we have long known that chronic stress effects arise from maladaptive expression of acute stress response pathways, predicting where...

Saraiva, J. L., Rachinas-Lopes, P., Arechavala-Lopez, P. 2022. Finding the “golden stocking density”: A balance between fish welfare and farmers’ perspectives. Frontiers in Veterinary Science 9, 930221.

The effects of stocking density on fish welfare are complex and involve many interacting parameters. This complex relationship between fish welfare, stocking density and influencing factors make it challenging to define a specific optimal (“golden”)...

Schwarzer, A., Erhard, M., Schmidt, P. et al. 2022. Effects of stocking rate and environmental enrichment on the ontogeny of pecking behavior of laying hen pullets confined in aviary compartments during the first 4 weeks of life. Animals 12(19), 2639.

The objective of this study was to describe the ontogeny of the severe feather pecking (SFP), gentle feather pecking (GFP), aggressive pecking (AP), and enrichment pecking (EP) of non-beak-trimmed Lohmann Brown (LB)-pullets during the first...

Torgerson-White, L., Sánchez-Suárez, W. 2022. Looking beyond the shoal: Fish welfare as an individual attribute. Animals 12(19), 2592.

Welfare is an individual attribute. In general, providing captive nonhuman animals with conditions conducive to good welfare is an idea more easily applied when dealing with few individuals. However, this becomes much harder—if not impossible—under...

van der Eijk, J. A. J., Gunnink, H., Melis, M. et al. 2022. Reducing stocking density benefits behaviour of fast- and slower-growing broilers. Applied Animal Behaviour Science 257, 105754.

The broiler industry has come under sustained pressure from welfare organizations to improve broiler welfare. Breed and stocking density are important factors for broiler welfare and are often specified as criteria for higher welfare systems...

Mumm, L. E., Mans, C. 2022. Evaluation of dexmedetomidine-midazolam sedation in budgerigars (Melopsittacus undulatus). Journal of the American Veterinary Medical Association 260(10), 1194–1199.

OBJECTIVE To evaluate the sedative effects of IM administration of a high or low dose of dexmedetomidine in combination with midazolam in budgerigars (Melopsittacus undulatus). ANIMALS 20 healthy adult budgerigars. PROCEDURES In a prospective, randomized...

Oliveira, A. R., Gozalo-Marcilla, M., Ringer, S. K. et al. 2021. Development, validation, and reliability of a sedation scale in horses (EquiSed). Frontiers in Veterinary Science 8, 611729.

The lack of standardization of sedation scales in horses limits the reproducibility between different studies. This prospective, randomized, blinded, horizontal and controlled trial aimed to validate a scale for sedation in horses (EquiSed). Seven horses...

Robinson, L. M., Waran, N. K., Handel, I. et al. 2021. Happiness, welfare, and personality in rhesus macaques (Macaca mulatta). Applied Animal Behaviour Science 236, 105268.

When we treat an animal’s welfare as an individual experience, we should consider the possibility that it may be associated with individual differences in personality. We tested for such associations in 44 socially housed rhesus...

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...

Haertel, A. J., Schultz, M. A., Colgin, L. M. et al. 2021. Predictors of subcutaneous injection site reactions to sustained-release buprenorphine in rhesus macaques (Macaca mulatta). JAALAS 60(3), 329-336.

Subcutaneous injection site reactions to sustained-release buprenorphine hydrochloride (Buprenorphine SR) in macaques have been reported in only a single case report. In the current study, we evaluated the incidence rate and predictors of buprenorphine SR...

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)...

Kälin, I., Henze, I. S., Ringer, S. K. et al. 2021. Comparison of recovery quality following medetomidine versus xylazine balanced isoflurane anaesthesia in horses: A retrospective analysis. Animals 11(8), 2440.

Medetomidine partial intravenous anaesthesia (PIVA) has not been compared to xylazine PIVA regarding quality of recovery. This clinical retrospective study compared recoveries following isoflurane anaesthesia balanced with medetomidine or xylazine. The following standard protocol was...

Pomerantz, O., Capitanio, J. P. 2021. Temperament predicts the quality of social interactions in captive female rhesus macaques (Macaca mulatta). Animals 11(8), 2452.

Previous reports suggest that female macaques with greater similarity in emotionality and nervous temperament, as evaluated in a well-established BioBehavioral Assessment (BBA) at the California National Primate Research Center, were more likely to form successful...

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...