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. 
Bozzay, J. D., Walker, P. F., Atwood, R. E. et al. 2023. Development, refinement, and characterization of a nonhuman primate critical care environment. PLOS ONE 18(3), e0281548.

Systemic inflammatory response remains a poorly understood cause of morbidity and mortality after traumatic injury. Recent nonhuman primate (NHP) trauma models have been used to characterize the systemic response to trauma, but none have incorporated...

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)...

Danforth, M. D., Clyde, V. L., Jourdan, B. et al. 2023. Blood pressure monitoring in zoologically managed bonobos (Pan paniscus). American Journal of Primatology 85(3), e23474.

In response to the growing evidence that hypertension may play a significant role in the development of cardiovascular disease (CVD) in bonobos, the Great Ape Heart Project established a finger blood pressure (BP) monitoring protocol...

Higham, J. P., Cooper, E. B., Whalen, C. et al. 2023. Urinary cytokine measurements do not reflect surgery-induced inflammation in rhesus macaques. American Journal of Primatology 85(8), e23506.

Measurement of the health and disease status of free-ranging primates is often limited by a lack of available biomarkers of immune activation and inflammation that can be applied noninvasively via the measurement of urine or...

Alizadeh, E. A., Graf, K., Schiwon, J. et al. 2023. Thirty years of telemetry-based data acquisition for cardiovascular drug safety evaluation: Applications and optimization. Journal of Pharmacological and Toxicological Methods 122, 107279.

Conducting safety evaluations of new drugs using conscious animals has been a specialty of our working group for thirty years. In this article, we review the various technical challenges and solutions dealt with over the...

Broche, N., Mouri, K., Suzumura, T. et al. 2023. Measuring short-term changes in stress-associated salivary analytes in free-ranging Japanese macaques (Macaca fuscata). Primates 64(4), 439–449.

Monitoring short-term changes of endocrine responses in non-human primates living in wild populations is a challenge. Saliva contains enzymes, steroids, and various analytes that can be broadly useful for helping us understand physiological responses to...

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...

Hube, D., van Meegen, C., Herbrandt, S. et al. 2023. Hair corticosterone concentration as a potential stress marker in pet rabbits. Veterinary Record 193(9), e3464.

Background As a prey species, rabbits tend to hide their illnesses and injuries. Consequently, pet rabbit owners often do not notice that their pet may be suffering. Methods Data on the housing and health of...

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...

Edes, A. N., Zimmerman, D., Jourdan, B. et al. 2022. Value ranges and clinical comparisons of serum DHEA-S, IL-6, and TNF-α in western lowland gorillas. Animals 12(19), 2705.

Physiological data can provide valuable information about the health and welfare of animals. Unfortunately, few validated assays and a lack of information on species-typical levels of circulating biomarkers for wildlife make the measurement, interpretation, and...

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...

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...

Kishida, T., Motokawa, Y., Yokoi, R. et al. 2022. Less invasive, simultaneous, and continuous measurements of locomotor activity and body temperature using the nano tag® small accelerometer device in cynomolgus monkeys. Journal of Pharmacological and Toxicological Methods 118, 107224.

Locomotor activity and body temperature evaluations of cynomolgus monkeys are useful to understand the effects of drugs on the central nervous system. Here, we describe a simple, inexpensive, and less invasive evaluation method using the...

Prior, H., Holbrook, M. 2021. Strategies to encourage the adoption of social housing during cardiovascular telemetry recordings in non-rodents. Journal of Pharmacological and Toxicological Methods 108, 106959.

The National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) is working with industry to promote social housing during cardiovascular telemetry recordings within non-rodent safety pharmacology and toxicology studies. Following surveys...

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...

Chmurska-Gąsowska, M., Sowińska, N., Pałka, S. et al. 2021. Non-invasive measurement of thyroid hormones in domestic rabbits. Animals 11(5), 1194.

Thyroid hormones are essential for metabolism, energy homeostasis and reproduction. Hormones can be measured in various biological source materials: blood, feces, urine, saliva and others. The aim of our study was to verify usefulness of...

Yolles, J. N., Lee-Stubbs, R. B. 2021. Comparison of direct and indirect methods of measuring arterial blood pressure in healthy, anesthetized African green monkeys (Chlorocebus aethiops). JAALAS 60(2), 229-237.

Quantitative blood pressure measurement is a critical parameter for assessing cardiovascular health, monitoring physiologic status under anesthesia, and making clinical decisions. The placement of an arterial catheter is the most accurate way to measure blood...

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., Brand, C. M. 2021. Age, sex, and inflammatory markers predict chronic conditions, cardiac disease, and mortality among captive western lowland gorillas (Gorilla gorilla gorilla). Primates 62(6), 931-943.

In humans, inflammatory markers predict health risks. As great apes experience many similar conditions, measuring inflammation may provide valuable health information. We examined four serum inflammatory markers in zoo-housed gorillas (n = 48): albumin, CRP, IL-6, and...

Anderson, J., Kaplan-Stein, S., Adolph, S. et al. 2020. Assessment of non-contact infrared thermometer measurement sites in birds. Journal of Applied Animal Welfare Science 23(2), 131-139.

The standard method of obtaining body temperature in a bird can be a stressful event, making routine evaluations challenging. Twenty-eight privately owned birds in good health were enrolled in the study to compare digital and...

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...

Cloutier Barbour, C., Danforth, M. D., Murphy, H. et al. 2020. Monitoring great ape heart health through innovative electrocardiogram technology: Training methodologies and welfare implications. Zoo Biology 39(6), 443-447.

Assessing and treating cardiovascular disease (or heart disease) is a growing concern for institutions housing great apes, as it is a major cause of mortality in all four taxa managed in human care. As part...

McFarland, R., Barrett, L., Fuller, A. et al. 2020. Infrared thermography cannot be used to approximate core body temperature in wild primates. American Journal of Primatology 82, e23204.

Understanding the physiological processes that underpin primate performance is key if we are to assess how a primate might respond when navigating new and changing environments. Given the connection between a mammal's ability to thermoregulate...

Pedersen, I. J., Forkman, B. 2019. Improving leg health in broiler chickens: A systematic review of the effect of environmental enrichment. Animal Welfare 28(2), 215-230.

Leg problems are highly prevalent in modern broiler production and provision of environmental enrichment could be a strategy to improve leg health. Different types of environmental enrichment have undergone evaluation. Our objective was to conduct...