3Rs Information - Fish

Zebrafish welfare

A number of papers on zebrafish welfare and the 3Rs have been published. We recommend that researchers using zebrafish, as well as ethics committees, AWBs and information officers in establishments that keep zebrafish are familiar with these publications:

i. The importance of ethical considerations surrounding fish in research

ii. The impact of invasive procedures on the patterns of movement of zebrafish

iii. Is heightened-shoaling a good candidate for positive emotional behaviour in zebrafish?

iv. The effects of environmental enrichment on survivorship, growth, sex ratio and behaviour in laboratory maintained zebrafish Danio rerio.

v. Welfare challenges influence the complexity of movement: fractal analysis of behaviour in zebrafish
vi. Zebrafish housing and husbandry recommendations 
vii. Enrichment for laboratory zebrafish - a review of the evidence and the challenges 

NC3Rs zebrafish resources

The team at the UK’s NC3Rs have grouped all resources and outputs from their science programmes relating to zebrafish welfare into a consolidated resource hub on their website. Topics covered include refinements for common procedures, welfare monitoring and anaesthesia.

Anaesthesia for fish in aquaculture research

The Fondazione Guido Bernandini (FGB) held a course in anaesthesia for fish in aquaculture research in March 2018 in Norway. They have published the presentations from this course, which include information on pain management, anaesthesia and analgesia in species such as zebrafish, lumpfish and salmon. This is recommended reading for all users of fish in Ireland.


Social housing aids recovery from stressors in zebrafish

A study from researchers at the University of Liverpool, in collaboration with the NC3Rs, has demonstrated that group housed zebrafish show lower levels of stress and anxiety when they undergo stressful or painful procedures like fin clipping than those who are housed singly. The research group also validated the use of water-borne cortisol siphoned from tanks as an accurate and non-invasive measure of physiological stress. This is recommended reading for all establishments with zebrafish colonies and should be considered by both the animal welfare body and the relevant users:



Zebrafish analgesia

An article has been published in Applied Animal Behaviour Science on the use of immersion analgesics in zebrafish. This article supports the use of immersion analgesia as a means of refining painful procedures in zebrafish such as fin-clipping and cardiac cryoinjection. If you are interested in further information on a suggested protocol for the provision of immersion analgesia to zebrafish undergoing these types of procedures, please contact sap@hpra.ie.


All eyes on zebrafish

An interesting article about the growing interest in zebrafish science has been published in the September 2017 edition of LabAnimal. This article should be of interest to scientists currently using, or considering using, zebrafish as their animal model.


The fish behaviour index for zebrafish monitoring

An automated monitoring tool has been developed by University of Liverpool researchers (funded by the NC3Rs) for gauging the behavioural status of zebrafish. This approach allows the user to identify and assess pain in zebrafish using a camera and tracking software to track the 3D trajectories of single fish. A video camera is required but the software is free to download.

An additional notable finding of the study was that application of lidocaine after fin clipping resulted in behaviours that most consistently aligned with observations in the control group, suggesting that it was the most successful method of analgesia tested. The authors of the study recommend that analgesia should be provided for invasive procedures (e.g. fin clipping) that cause tissue damage and may cause pain, unless to do so would confound data collection.

FELASA guidelines on zebrafish housing and husbandry

 A joint working group, with members from the European Society for Fish Models in Biology and Medicine (EUFishBioMed) and the Federation of European Laboratory Animal Science Associations (FELASA) has published an article on housing and husbandry recommendations for zebrafish. The recommendations provide guidance on best practices and ranges of husbandry parameters within which zebrafish welfare, as well as reproducibility of experimental procedures, are assured.

Evolution of nociception and pain: evidence from fish models

Dr Lynne Sneddon has published a review article about nociception and pain, which describes how fish react to painful events and respond to pain-relieving drugs, concluding that there is ample evidence to demonstrate that fish experience pain and that pain-related behavioural changes are conserved across vertebrates.

Intermittent flow respirometry

A paper published in the Journal of Experimental Biology aims to provide the first guidelines for reporting intermittent-flow respirometry methods used in aquatic animals. The guidelines take the form of a checklist of criteria that the authors of the paper consider to be the minimum required for the interpretation, evaluation and replication of experiments using intermittent-flow respirometry.

Fish identification & marking

In collaboration with external experts, the Swedish 3Rs Centre has compiled the most common methods for marking fish into a guideline, which has now been translated into English. The advantages and disadvantages of each marking and tagging method are evaluated from an animal welfare, as well as a users’ point-of-view. The guideline includes information on both free-living fish and fish in animal facilities.


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