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. 
de Castro Lippi, I. C., Caldara, F. R., de Lima Almeida Paz, I. C. et al. 2022. Global and Brazilian scenario of guidelines and legislation on welfare in pig farming. Animals 12(19), 2615.

The evolution of scientific knowledge regarding animal sentience, together with the growing concerns of consumers regarding current production models, has brought with it the responsibility of reviewing many practices carried out in industrial swine farming...

de Jong, I. C., Schokker, D., Gunnink, H. et al. 2022. Early life environment affects behavior, welfare, gut microbiome composition, and diversity in broiler chickens. Frontiers in Veterinary Science 9, 977359.

This study aimed to identify whether early-life conditions in broiler chickens could affect their behavior and welfare, and whether or not this was associated with an altered gut microbiome composition or diversity. Broilers were tested...

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...

Li, W., Yan, C., Descovich, K. et al. 2022. The effects of preslaughter electrical stunning on serum cortisol and meat quality parameters of a slow-growing Chinese chicken breed. Animals 12(20), 2866.

Electrical stunning is widely utilized prior to a neck cut to induce unconsciousness in order to improve animal welfare and slaughter efficiency in the broiler production industry. However, slaughter without stunning is still very commonly...

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...

Mota-Rojas, D., Velarde, A., Marcet-Rius, M. et al. 2022. Analgesia during parturition in domestic animals: Perspectives and controversies on its use. Animals 12(19), 2686.

This article analyzes the physiological role of pain during parturition in domestic animals, discusses the controversies surrounding the use of opioids, non-steroidal anti-inflammatory drugs (NSAIDs), and local analgesics as treatments during labor, and presents the...

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...

Parois, S. P., Van Der Zande, L. E., Knol, E. F. et al. 2022. A multi-suckling system combined with an enriched housing environment during the growing period promotes resilience to various challenges in pigs. Scientific Reports 12(1), 6804.

Little is known about the impact of social and environmental enrichment on improving livestock resilience, i.e. the ability to quickly recover from perturbations. We evaluated the effect of an alternative housing system (AHS) on resilience...

Pedersen, K., Kruhøffer, L. L., Lykkesfeldt, J. et al. 2022. Comparison of the neuromuscular effects of two infusion rates of rocuronium in anesthetized pigs. Acta Veterinaria Scandinavica 64(1), 38.

Neuromuscular blocking agents are frequently administered to pigs used for research. In humans, administration of the drugs is not without risk and may result in accidental awareness under general anaesthesia and postoperative residual neuromuscular blockade...

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...

Söbbeler, F. J., Wendt, S., Briese, A. et al. 2022. Comparative study of pain-related responses of male piglets up to seven days of age to the application of different local anaesthetics and subsequent castration. Animals 12(20), 2833.

To evaluate pain responses to intratesticular and subscrotal injection of three local anaesthetics and their efficacy during castration a randomized controlled study was conducted. In groups of 20 piglets, procaine (2%), lidocaine (2%), or mepivacaine...

Weisskopf, M., Glaus, L., Trimmel, N. E. et al. 2022. Dos and don’ts in large animal models of aortic insufficiency. Frontiers in Veterinary Science 9, 949410.

Aortic insufficiency caused by paravalvular leakage (PVL) is one of the most feared complications following transcatheter aortic valve replacement (TAVI) in patients. Domestic pigs (Sus scrofa domestica) are a popular large animal model to study...

Xu, D., Shu, G., Liu, Y. et al. 2022. Farm animal enrichments improve the welfare of layer chicks and pullets: A comprehensive review. Animals 12(19), 2610.

Currently, cage housing is regarded as a global mainstream production system for laying hens. However, limited living space and confinement of birds in cages cause welfare and health problems, such as feather pecking, osteoporosis, obesity...

Lima, A. F., Lima, S. G. C., Nogueira-Filho, S. L. G. et al. 2022. Vocal expression of emotions in farmed spotted paca (Cuniculus paca). Applied Animal Behaviour Science 256, 105753.

Vocal emissions in non-human mammals can be used as non-invasive indicators of animal emotion and welfare. Therefore, we aimed to validate the use of acoustic parameters as indicators of affective states and welfare in farmed...

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...

Cordoni, G., Collarini, E., Gioia, M. et al. 2022. Play fighting versus real fighting in piglets (Sus scrofa): Similar patterns, different structure. Behavioural Processes 203, 104778.

When animals engage in ‘non-serious’ fighting (play-fighting) they ‘borrow’ motor patterns especially from the aggressive context. It may be difficult to distinguish play- and real-fighting. This is particularly true for piglets (Sus scrofa), which can...

Bist, R. B., Chai, L. 2022. Advanced strategies for mitigating particulate matter generations in poultry houses. Applied Sciences 12(22), 11323.

Poultry farming plays a key role in agricultural air emissions. Particulate matter (PM) level tends to be high in broiler and cage-free layer houses, that may impair health and welfare of animals and their caretakers...

Brando, S., Coe, J. 2022. Confronting back-of-house traditions: Primates as a case study. Journal of Zoological and Botanical Gardens 3(3), 366–397.

This review commentary focuses on traditional management practices and facility design with suggested improvements in non-public primate management areas, often called “back-of-house”, (henceforth BOH) in zoos, sanctuaries, and research facilities. Progress has been made toward...

Ginovart-Panisello, G. J., Iriondo Sanz, I., Panisello Monjo, T. et al. 2022. Trend and representativeness of acoustic features of broiler chicken vocalisations related to CO2. Applied Sciences 12(20), 10480.

The concentration of CO2 is relatively large in poultry farms and high accumulations of this gas reduce animal welfare. Good control of its concentration is crucial for the health of the animals. The vocalizations of...

Riedel, A., Rieke, L., Kemper, N. et al. 2022. A place to be? Use of winter gardens with and without automatic enrichment devices by laying hens. Applied Sciences 12(7), 3650.

Since the abolition of beak trimming in laying hens in Germany, the importance of adequate enrichment material to help reduce feather pecking and cannibalism has grown. Here we tested an automatic enrichment device dosing grain...

Schwarzer, A., Rauch, E., Bergmann, S. et al. 2022. Risk factors for the occurrence of feather pecking in non-beak-trimmed pullets and laying hens on commercial farms. Applied Sciences 12(19), 9699.

Severe feather pecking (SFP) is a behavioral disorder, for which there are multifactorial reasons. Various aspects of pullet and laying-hen husbandry—including housing conditions, management, feeding, and genetics—must be considered, to prevent negative outcomes, such as...

Skade, L., Kristensen, C. S., Nielsen, M. B. F. et al. 2021. Effect of two methods and two anaesthetics for local anaesthesia of piglets during castration. Acta Veterinaria Scandinavica 63, 1.

Since January 2019, surgical castration of male piglets must be performed using local anaesthesia, if farmers deliver pigs to the primary exporting slaughterhouses according to the “Danish quality scheme”; a voluntary initiative taken by the...

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...

Luna, D., González, C., Byrd, C. J. et al. 2021. Do domestic pigs acquire a positive perception of humans through observational social learning? Animals 11(1), 127.

Farm animals can perceive humans positively by observing another animal being positively handled. This study evaluated whether pigs acquire a positive perception of humans after observing either a high or low socially ranked conspecific receiving...