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. 
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...

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...

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...

Garai, M. E., Roos, T., Eggeling, T. et al. 2022. Developing welfare parameters for African elephants (Loxodonta africana) in fenced reserves in South Africa. PLOS ONE 17(3), e0264931.

South Africa has many fenced reserves harbouring small to medium sized populations of African elephant (Loxodonta africana), most of which have been translocated. Elephants on fenced reserves may be exposed to various management interventions and...

Zhang, J., Yu, L., Yin, G. 2022. Evaluation of behavior and affective state of different-parity sows with strong/weak pupil light reflex. Animals 12(9), 1184.

The stall-housing system is commonly used in the modern swine industry in many countries; however, long-term space restrictions can cause affective and physiological abnormalities in sows. The pupil light reflex (PLR) can reflect the psychological...

Knaebe, B., Weiss, C. C., Zimmermann, J. et al. 2022. The promise of behavioral tracking systems for advancing primate animal welfare. Animals 12(13), 1648.

Recent years have witnessed major advances in the ability of computerized systems to track the positions of animals as they move through large and unconstrained environments. These systems have so far been a great boon...

Lou, M. E., Porter, S. T., Massey, J. S. et al. 2022. The application of 3D landmark-based geometric morphometrics towards refinement of the piglet grimace scale. Animals 12(15), 1944.

Proper methods of assessment to objectively identify pain are essential for welfare improvements of piglets undergoing surgical castration on commercial farms. The Piglet Grimace Scale (PGS) is used to identify changes in facial expressions caused...

Paterson, E. A., Turner, P. V. 2022. Challenges with assessing and treating pain in research primates: A focused survey and literature review. Animals 12(17), 2304.

Research primates may undergo surgical procedures making effective pain management essential to ensure good animal welfare and unbiased scientific data. Adequate pain mitigation is dependent on whether veterinarians, technicians, researchers, and caregivers can recognize and...

Drexl, V., Dittrich, I., Haase, A. et al. 2022. Tail posture as an early indicator of tail biting - A comparison of animal and pen level in weaner pigs. Applied Animal Behaviour Science 252, 105654.

The occurrence of tail biting is one of the most important animal welfare problems in pig farming and needs to be recognised early to reduce injuries and suffering. The posture of the tail could be...

O'Malley, C. I., Hubley, R., Tambadou, H. et al. 2022. Refining restraint techniques for research pigs through habituation. Frontiers in Veterinary Science 9, 1016414.

Pigs are common research models and are strong animals that can be difficult to restrain. Improper restraint can put pigs and research personnel at risk for injury and induce stress, which can affect research outcomes...

Guevara, R. D., Pastor, J. J., Manteca, X. et al. 2022. Systematic review of animal-based indicators to measure thermal, social, and immune-related stress in pigs. PLOS ONE 17(5), e0266524.

The intense nature of pig production has increased the animals’ exposure to stressful conditions, which may be detrimental to their welfare and productivity. Some of the most common sources of stress in pigs are extreme...

Korenyi-Both, J., Vidaurre, J., Held, T. et al. 2022. Description of electroencephalographic data gathered using water-based medium-expansion foam as a depopulation method for nursery pigs. Scientific Reports 12(1), 16798.

The United States’ swine industry is under constant threat of foreign animal diseases, which may emerge without warning due to the globalized transportation networks moving people, animals, and products. Therefore, having disease control and elimination...

Archer, C., Garcia, A., Henderson, M. et al. 2022. Olfactory enrichment using a maternal pheromone improved post-weaning pig performance and behavior. Frontiers in Veterinary Science 9, 965370.

The post-weaning environment in commercial pig nursery buildings is typically devoid of both the sow and her semiochemicals. Among other factors, the loss of maternal odors may contribute to post-weaning stress. In this work, we...

Fischer-Tenhagen, C., Meier, J., Pohl, A. 2022. “Do not look at me like that”: Is the facial expression score reliable and accurate to evaluate pain in large domestic animals? A systematic review. Frontiers in Veterinary Science 9, 1002681.

Facial expression scoring has proven to be useful for pain evaluation in humans. In the last decade, equivalent scales have been developed for various animal species, including large domestic animals. The research question of this...

Korenyi-Both, J., Vidaurre, J., Held, T. et al. 2022. Description of electroencephalographic data gathered using water-based medium-expansion foam as a depopulation method for nursery pigs. Scientific Reports 12(1), 16798.

The United States’ swine industry is under constant threat of foreign animal diseases, which may emerge without warning due to the globalized transportation networks moving people, animals, and products. Therefore, having disease control and elimination...

Martin, J. E., Baxter, E. M., Clarkson, J. M. et al. 2022. Characterizing candidate decompression rates for hypobaric hypoxic stunning of pigs. Part 1: Reflexive behavior and physiological responses. Frontiers in Veterinary Science 9, 1027878.

Alternatives to carbon dioxide (CO2) stunning for the commercial slaughter of pigs are urgently needed because there is robust evidence that exposing pigs to hypercapnic environments is associated with pain, fear, and distress. Hypobaric hypoxia...

Munday, C., Rose, P. 2022. Envirionmental and social influences on the behaviour of free-living mandarin ducks in richmond park. Animals 12(19), 2554.

Many species of birds are housed in zoos globally and are some of the most popular of animals kept under human care. Careful observations of how species live and behave in their natural habitats can...

O’Malley, C. I., Hubley, R., Tambadou, H. et al. 2022. Refining restraint techniques for research pigs through habituation. Frontiers in Veterinary Science 9, 1016414.

Pigs are common research models and are strong animals that can be difficult to restrain. Improper restraint can put pigs and research personnel at risk for injury and induce stress, which can affect research outcomes...

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”)...

Manning, P., Hauff, L., Padfield, C. et al. 2022. Can stress and anxiety be assessed in African elephants (Loxodonta africana) using self-directed behaviour? Applied Animal Behaviour Science 256, 105746.

Captive African elephants used in the tourism industry face numerous welfare issues which are often stress related and linked to high numbers of tourists or human-elephant interactions. Elephant welfare is commonly assessed by quantifying faecal...

Anderson, M. G., Campbell, A. M., Kuhn, D. D. et al. 2022. Impact of environmental complexity and stocking density on affective states of rainbow trout (Oncorhynchus mykiss). Animal Cognition 25(5), 1331–1343.

Environmental condition, such as environmental complexity or stocking density, can directly or indirectly influence animal emotion and ultimately, affective state. Affective states of animals can be assessed through judgement bias tests, evaluating responses to ambiguous...

Hepps Keeney, C., Harrison, T. M. 2022. Euthanasia complications in non-domestic species. Journal of Zoological and Botanical Gardens 3(4), 616–623.

There are very few studies describing euthanasia complications in non-domestic species. The goal of this study was to survey veterinarians to determine what complications may commonly occur during the euthanasia of non-domestic species. An online...

Husheer, J., Luepke, M., Dziallas, P. et al. 2021. Electrocution as an alternative euthanasia method to blunt force trauma to the head followed by exsanguination for non-viable piglets. Acta Veterinaria Scandinavica 62, 67.

On farms, the currently approved and most widely practised method of euthanising non-viable piglets is blunt force trauma to the head followed by exsanguination. However, the use of this method is criticised due to public...

Casey, K. M., Gore, F., Vilches-Moure, J. G. et al. 2021. Management of morbidity and mortality in a New Zealand white rabbit model of steroidinduced osteonecrosis of the femoral head. Comparative Medicine 71(1), 86-98.

Steroid-induced osteonecrosis of the femoral head (SONFH) is a condition documented in humans and animals exposed to chronic steroid administration. The rabbit has become a preferred animal model for investigating the pathogenesis and treatment of...

Wiechers, D.-H., Brunner, S., Herbrandt, S. et al. 2021. Analysis of hair cortisol as an indicator of chronic stress in pigs in two different farrowing systems. Frontiers in Veterinary Science 8, 605078.

Confinement to farrowing crates is known to prevent sows from performing natural behavior, impairing animal welfare and possibly causing chronic stress. Hair cortisol analyses are increasingly used to detect chronic stress in animals. In the...