To reduce the number of animals used in research
Researchers around Sweden are engaged in many activities to reduce the number of animals used in their research.
We have contacted several researchers and asked them to describe their research and its connection to the 3Rs and the reduction of animals used in research.
Vascular Medicine research
Hello, Ljubica Matic, Associate Professor and Group Leader for Translational Vascular Medicine at Karolinska Institutet, and Hong Jin, MD, PhD, Senior Research Specialist and Animal lab manager at Karolinska Institutet!
What is the main focus in your research?
Our research focuses on pathophysiology of vascular diseases, to discover novel molecular mechanisms of vascular disease related to smooth muscle cells. These are then evaluated as a source of biomarkers and therapeutic targets in atherosclerosis. We combine bioinformatic and clinical data studies from human biobanks with rodent models of vascular injury and disease, as well as with in vitro systems based on cells and tissue explants.
How do you work to reduce the number of animals in your research? Also, how do you work to refine your animal experiments?
As animal models are still needed in our research, we have gathered both clinical vascular surgeons and animal experts, such as Hong Jin, in our group to apply various strategies to address all 3Rs.
One of the most effective ways we have found for reduction, is setting up biobanks of specimens and omics datasets from technically difficult vascular models. The specimens and data are shared worldwide, alleviating the need that the same experiments are performed in other labs multiple times.
By using ultrasound both for longitudinal imaging and to follow-up of disease development, we can avoid sacrificing mice in each time-point. This also enables local delivery of drugs, raise the efficacy, reduce the drug dosage and mice numbers. We have been able to refine vascular models, that normally carry higher severity, to achieve an equivalent phenotype without the severe outcome. This should eventually lead to a change of the standard in the field.
Our group has also held courses on PhD level for many years, to teach the basics of cardiovascular disease and animal models, as well as how to avoid post-surgical complications and perform these models in a responsible way.
In your opinion – what is the main challenge when it comes to reducing the number of animals in research?
We often use mice with genetic modifications, often double or triple knockout mice from many generations of cross breeding. In combination with high fat diet, vascular surgery or injection of drugs, we can fully assess the function of our gene of interest. Over the years, we have been able to refine our models to achieve lower severity and replace some models with ex vivo studies. However, we still have two main challenges:
- reduction of mice numbers through novel breeding strategies and
- maintaining and developing surgical expertise and competency in working with these models in a responsible and consistent way.
We learned about your 3Rs work from the retrospective assessment performed by the Central Ethics Committee on Animal Experiments. As a researcher, what use do you have of the retrospective assessment? And how do you use it?
The retrospective assessment has been particularly useful in cases where an important step in our animal experiments needed a deeper analysis, a clearer explanation or a reflection on how to adjust our protocols with policy settings with the aim to better achieve desired outcomes in research. Going back through the already performed experimental work in this way gives a perspective of wholeness, resulting in a better vision of what needs to be changed for the future.
Mice breeding
Hello, Anne Edenro, Head of the Experimental Biomedicine unit (EBM) at the University of Gothenburg!
What is the main focus in your research?
At EBM, a high number of transgenic mouse strains have been held in maintenance breeding, for years, without being used in experiments. This was first observed by animal technicians. Not only does this over breeding lead to numerous mice being euthanized with no purpose, but it also adds extra stress and discomfort among employees that carries out euthanization of these mice.
Higher management was informed of this discovery, and once the question was raised within the organization, discussions took place about how to minimize unnecessary breeding.
How do you work to reduce the number of animals in your research? Also, how do you work to refine your animal experiments?
To ensure that mouse strains are not kept on the shelf without being used, we needed to understand why it happens and find ways to make it easy for the researcher to avoid over breeding. As a result, our facility now has a Breeding policy, which works as a guidance and base for discussion when talking to researchers.
We have also established routines to help researchers cryopreserve their mouse strains in order to make it as easy as possible to get the strains from the shelf to the freezer. After noting that researchers had to invest a lot of time to find out where and how to reach companies and institutions that offer cryopreservation, we now do this on their behalf. In some cases, when we find that the strain is already frozen or available to buy from a company, we can give the advice to close the strain until new animals are needed.
Animal care takers are encouraged to ask questions and involve our breeding responsible person, when they see strains not being used for more than 6 months. Avoiding unnecessary breading is now also on the agenda every time a new Ethical application is brought to the Ethical Consultation Meeting (samrådsmöte).
In your opinion – what is the main challenge when it comes to reducing the number of animals in research?
Many researchers have little time to spend outside their research focus. We work to create awareness about the benefits of cryopreservation. Not only does it avoid unnecessary breeding, cryopreservation also lowers the risk of genetic drift or a strain being lost if something happens in the animal facility, eg. infection, fire or mix-up.
By using our time and knowledge we can free up space in the animal unit, reduce costs and reduce the unnecessary number of mice produced.
Monitoring of wild fish
Hello, Jens Olsson, researcher in Marine Ecology and Coastal fish Dynamics at the Swedish University of Agricultural Sciences!
What is the main focus in your research?
My work focuses on coordinating the monitoring of fish communities along the Swedish coasts, which also includes developing monitoring methods with good precision and lowered environmental impact. Based on the data my colleagues and I collect we develop tools and indicators to assess the status of the targeted fish communities.
The results of our work are frequently used in local and national fish management and for reporting the status of coastal ecosystems to EU and other international management bodies.
How do you work to reduce the number of animals in your research? Also, how do you work to refine your animal experiments?
The current monitoring methods we apply to survey the status of fish along the coasts are invasive and includes gillnets in which the fish caught dies, and fyke nets in which the majority of the fish caught can be released back to the water alive. As our monitoring kills a lot of fish, we are constantly aiming at refining the current methods by reducing the number of fishing gear used while also optimizing the precision and quality in data.
In this year we are launching a three-year project where we pilot alternative methods to survey fish as a complement to the already in place. We are testing hydro-acoustics methods (using echosounders) and environmental DNA (eDNA) in parallel with our current monitoring methods.
The new methods have been successfully used in other aquatic systems, and now we will evaluate their performance in coastal systems and lakes, and if they can serve as potential complements and generate additional and valuable data for fish in Swedish waters.
In your opinion – what is the main challenge when it comes to reducing the number of animals in research?
There are two main challenges when applying new methods to reduce the number of fishes killed during surveys.
First, the management advice we produce often includes information on the age and size of the fish as these parameters bring key information on the status of fish populations. Collecting data on age and size requires capturing the fish by invasive and often also lethal methods.
Second, since our results are commonly relying on addressing trends over time in fish community status, introducing new methods requires careful and often challenging calibration procedures across methodologies. A new method can for example only be applied after being run in parallel with existing methods for at least a period of five years.
Senast uppdaterad: