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...

Sen Sarma, O., Frymus, N., Axling, F. et al. 2023. Optimizing zebrafish rearing−Effects of fish density and environmental enrichment. Frontiers in Behavioral Neuroscience 17, 1204021.

Despite its popularity in research, there is very little scientifically validated knowledge about the best practices on zebrafish (Danio rerio) husbandry, which has led to several facilities having their own husbandry protocols. This study was...

Clemente, G. A., Tolini, C., Boscarino, A. et al. 2023. Farmed fish welfare during slaughter in Italy: Survey on stunning and killing methods and indicators of unconsciousness. Frontiers in Veterinary Science 10.

Information on slaughter procedures for farmed fish in aquaculture is limited, both in Europe and in Italy, due to a general lack of field data. The aim of this study was to gather information on...

Leyden, C., Brüggemann, T., Debinski, F. et al. 2022. Efficacy of tricaine (MS-222) and hypothermia as anesthetic agents for blocking sensorimotor responses in larval zebrafish. Frontiers in Veterinary Science 9, 864573.

Tricaine, or MS-222, is the most commonly used chemical anesthetic in zebrafish research. It is thought to act via blocking voltage-gated sodium channels, though its mechanism of action, particularly at the neuronal level, is not...

Davis, A. K., Garner, J. P., Chu, D. K. et al. 2022. Propofol immersion as a euthanasia method for adult zebrafish (Danio rerio). Comparative Medicine 72(3), 204-209.

The exponential rise of the zebrafish (Danio rerio) as a model organism in biomedical research has far outstripped our un- derstanding of basic husbandry and welfare for this species. As a case in point, here...

Ferreira, J. M., Félix, L., Jorge, S. et al. 2022. Anesthesia overdose versus rapid cooling for euthanasia of adult zebrafish. Zebrafish 19(4), 148-159.

The rapid increase in zebrafish use needs to be accompanied by research into the refinement of procedures. The European (EU) Directive lists three possible euthanasia methods for fish: anesthetic overdose, electrical stunning, and concussion. However...

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”)...

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...

Owen, J. P., Kelsh, R. N. 2021. A suitable anaesthetic protocol for metamorphic zebrafish. PLOS ONE 16(3), e0246504.

Zebrafish are frequently used as a means to investigate development. These studies increasingly require repeated anaesthesia of zebrafish during juvenile (i.e. metamorphic) stages. The effects of anaesthesia during this time remain poorly studied. The aim...

Martini, A., Huysseune, A., Witten, P. E. et al. 2021. Plasticity of the skeleton and skeletal deformities in zebrafish (Danio rerio) linked to rearing density. Journal of Fish Biology 98(4), 971-986.

The teleost zebrafish (Danio rerio), an established model for human skeletal diseases, is reared under controlled conditions with defined parameters for temperature and photoperiod. Studies aimed at defining the proper rearing density have been performed...

Andersson, M., Kettunen, P. 2021. Effects of holding density on the welfare of zebrafish: A systematic review. Zebrafish 18(5), 297-306.

The zebrafish is becoming an increasingly popular research animal around the world. Its welfare is affected by an array of environmental factors, such as food access and water quality. Holding density is an important welfare...

Jorge, S., Ferreira, J. M., Olsson, I. A. S. et al. 2021. Efficacy and behavioral recovery of different anesthetics. Zebrafish 18(5), 330-337.

The use of proper anesthesia in zebrafish research is essential to ensure fish welfare and data reliability. However, anesthesia long-term side effects remain poorly understood. The purpose of this study was to assess anesthesia quality...

Musk, G. C., Ezzy, B. J., Kenchington, L. M. et al. 2020. A comparison of buffered tricaine methanesulfonate (MS-222) and isoeugenol anesthesia for caudal fin clipping in zebrafish (Danio rerio). JAALAS 59(6), 732-736.

The purpose of this study was to compare the safety and efficacy of buffered tricaine methanesulfonate (MS-222) and isoeugenol for the anesthesia of zebrafish undergoing caudal fin clipping. Eighty 9 mo Danio rerio (AB strain)...

Sloman, K, A., Bouyoucos, I. A., Brooks, E. J. et al. 2019. Ethical considerations in fish research. Journal of Fish Biology 94(4), 556-577.

In this review, we focus primarily on the refinement of common methods used in fish research based on emerging knowledge with the aim of improving the welfare of fish used in scientific studies. We consider...

Ehrlich, O., Karamalakis, A., Krylov, A. J. et al. 2019. Clove oil and AQUI-S efficacy for zebrafish embryo, larva, and adult anesthesia. Zebrafish 16(5), 451-459.

Since the use of the zebrafish Danio rerio genetic model organism within the scientific research community continues to grow rapidly, continued procedural refinement to support high-quality, reproducible research and improve animal welfare remains an important...

Dunford, K., Hakkesteeg, J., Wilson, C. 2019. Stiff as a board: Measuring rigor mortis in zebrafish. Animal Technology and Welfare 18(3), 203-205.

Schedule one killing (S1K) methods require a two-step process: a humane method of death, typically for Zebrafish an anaesthetic overdose and confirmation of death, such as confirmation of rigor mortis. There is widespread variation of...

Thurman, C. E., Rasmussen, S., Prestia, K. A. 2019. Effect of 3 euthanasia methods on serum yield and serum cortisol concentration in zebrafish (Danio rerio). JAALAS 58(6), 823–828.

Zebrafish are an important model in neuroscience and developmental biology and are also an emerging model in hematology and immunology. Little information is available for zebrafish regarding the physiologic impact of different euthanasia methods and...

Golledge, H., Carter, E. 2018. Welfare of fish farmed in the EU during transport and at slaughter. Animal Welfare 27(3), 287-288.

This Report, commissioned by the European Commission, summarises the current state of transport and slaughter practices in the aquaculture industry within eleven case-study countries in the European Economic Area (EAA). Comparisons are also made with...

Wallace, C. K., Bright, L. A., Marx, J. O. et al. 2018. Effectiveness of rapid cooling as a method of euthanasia for young zebrafish (Danio rerio). JAALAS 57(1), 58-63.

Despite increased use of zebrafish (Danio rerio) in biomedical research, consistent information regarding appropriate euthanasia methods, particularly for embryos, is sparse. Current literature indicates that rapid cooling is an effective method of euthanasia for adult...

Chatigny, F., Creighton, C. M., Stevens, E. D. 2018. Intramuscular infiltration of a local anesthetic, lidocaine, does not result in adverse behavioural side effects in rainbow trout. Scientific Reports 8, 10250.

Fish are a useful animal model for research, but our improvement in some aspects of their welfare has not kept pace with their increased popularity for this use. For example, researchers rarely use analgesics. We...

Pounder, K. C., Mitchell, J. L., Thomson, J. S. et al. 2018. Physiological and behavioural evaluation of common anaesthesia practices in the rainbow trout. Applied Animal Behaviour Science 199, 94-102.

Anaesthetic drugs are commonly administered to fish in aquaculture, research and veterinary contexts. Anaesthesia causes temporary absence of consciousness and may reduce the stress and/or pain associated with handling and certain invasive procedures. The rainbow...

Chatigny, F., Groman, D. B., Martinson, S. A. et al. 2018. Evaluation of tissue changes following intramuscular infiltration of lidocaine in rainbow trout Oncorhynchus mykiss. Journal of Fish Biology 92(4), 888-900.

Rainbow trout Oncorhynchus mykiss were infiltrated with either saline or lidocaine adjacent to the dorsal fin to assess histopathological changes. Infiltration was done as if it were being used as a local anaesthetic. Tissue lesions...

Köhler, A., Collymore, C., Finger-Baier, K. et al. 2017. Report of Workshop on Euthanasia for Zebrafish—A Matter of welfare and science. Zebrafish 14(6), 547-551.

The increasing importance of zebrafish as a biomedical model organism is reflected by the steadily growing number of publications and laboratories working with this species. Regulatory recommendations for euthanasia as issued in Directive 2010/63/EU are...

De Lombaert, M. C. M., Rick, E. L., Krugner-Higby, L. A. et al. 2017. Behavioral characteristics of adult zebrafish (Danio rerio) after MS222 anesthesia for fin excision. JAALAS 56(4), 377-381.

The health of laboratory animals is an ethical responsibility of researchers and a critical determinant of experimental outcome. Therefore, all Husbandry & Management procedures should be evaluated for their effects on mortality, behavior, and physiology...

Chatigny, F., Kamunde, C., Creighton, C. M. et al. 2017. Uses and doses of local anesthetics in fish, amphibians, and reptiles. JAALAS 56(3), 244-253.

Local anesthetics are an integral part of routine pain management in mammals, yet their use is relatively limited in fish, amphibians and reptiles. These animals frequently undergo potentially painful surgical procedures and therefore could possibly...