New guidelines are directly or indirectly enhancing animal welfare in experiments, and moving the 3Rs from a fixed descriptor to a moving document in the process

ARRIVE is a relatively new set of guidelines that help researchers plan their experiments in a way that maximize animal welfare and stress the 3Rs.

ALN spoke with Henk-Jan Schuurman, consultant and director of consultancy firm SchuBiomed Consultancy in the Netherlands, to learn more about his long history with the 3Rs and about exciting new animal welfare guidelines that will help advance the 3Rs.

What are your experiences with the 3Rs?

HS: When I started in experimental animal research in 1977 in the Faculty of Medicine, University of Utrecht, the Netherlands, there was little attention for 3Rs. This was despite a very active Department of Laboratory Animal Sciences in the faculty of Veterinary Medicine, headed by Prof Bert van Zutphen focusing in particular on alternatives for in vivo studies. By the end of the ‘80s, I joined as consultant the National Institute of Health and Environmental Protection in the Netherlands, and witnessed the in-depth judgment of experimental animal protocols where principles similar as the 3Rs were applied.

After I moved to Basel-CH to join transplantation research at Sandoz (later Novartis), the same applied for study protocols judged by the local government (canton) with lay people in the ethical committee: 3Rs were not mentioned by name but aspects of alternatives and replacement ranked high.

My colleagues were strong proponents of group housing, not only for animals in holding but also animals during transplantation experiments: we all were impressed how this accommodation reduced stress.

During this period I was involved in many international research collaborations, most of which were with transplant centers in the US, which like work in Europe did not address the 3Rs in particular. I was first exposed to the 3Rs when I moved to the US and started collaborating with Melanie Graham in the group in Minneapolis, where I saw the first attempts of the R of refinement in nonhuman primate studies.

Advanced preclinical research in transplantation is mainly conducted in larger animal species; since the last decade the respective groups gradually realize the impact of the 3Rs, but adherence to the 3R principles needs some more time: the group of Melanie Graham is leading in this area.

What can the laboratory animal science industry do to improve animal welfare in the laboratory?

HS: Workers in the field can do quite a lot to improve animal welfare in the laboratory. A major point is education. Many scientists working in experimental animal research perceive 3Rs as a factor which make their research complex and difficult: actually this is not the case. The R for Replacement is essentially a main part in applying for approval of study protocols, while the R for Refinement is essentially a main part in the design and conduct of experiments. The R for Reduction is somewhat in between.

I learned from being exposed to the 3Rs that Refinement not only is an issue of animal well-being, but also directly relates to Reduction: improved animal welfare by refinement (i.e., conduct of procedures that are less burdening and hence cause less stress, e.g., avoidance of putting animals in jackets and chair restraint, implementation of cooperative handling) leads to improved outcomes with less interference by confounding factors and thereby less inter-animal variation and thus reduction in the number of animals to achieve significance in data.

Education is needed for this aspect of the 3Rs. Evidently this involves also those workers in the field who oversee animals, animal protocols, and approval procedures in animal ethical committees. When scientists meet with veterinarians and animal care staff to discuss experimental studies and protocols, there is a task for staff in the animal facility to propose Refinement and associated procedures. Institutional Animal Care and Use Committees should have a focus on Refinement when reviewing protocols, besides considering aspects of Reduction and Replacement.

What sort of 3R innovations do you hope to see in the next 50 years?

HS: Regarding in vivo experiments, increasing awareness of Refinement will automatically lead to development and implementation of innovative procedures which can be simple but also complex.

It is foreseen that training in cooperative handling will become a mandatory standard. Implementation of chips and telemetry will enable to sample data keeping animals in their daily environment: it can be foreseen that sampling of blood will be eliminated. These and other technical improvements, including sensitivity and reproducibility of in vivo and ex vivo analytics, will indirectly add to Reduction of animals in experiments.

It can also be foreseen that experimental studies will increasingly be performed in genetically modified animals, enabling more homogeneous groups like inbred animals, resulting in less variability and Reduction in numbers of animals. At the other side, new approaches in in vitro and in silico experiments will enhance Replacement.

There will be a continued need for research in experimental animals to understand pathophysiological processes and effects on such processes in a living individual: however it will be increasingly possible to mimic such processes in in silico research and dissect such processes in in vitro studies, thereby reducing the need for studies in experimental animals.

How do you think the 3Rs changes animal research in the next 50 years?

HS: There will an increasing importance for animal welfare in experimental animal research. This means that the basics of the 3Rs will remain intact, but that the conditions of each R will be increasingly be defined in detail.

For instance, it can be foreseen that guidelines will be developed defining not only levels of animal well-being but also which level is allowed for which type of experiment. Also, a detailed evaluation of in vitro and in silico experiments may increasingly become important before approval for an in vivo experiment will be given.

This increased scrutiny in the conduct of experimental animal research will involve the scientist and staff in the experimental animal laboratory, but also the agencies providing funding and the institutions controlling the reporting. In some areas this is already happening, and for whole Europe there is a strict directive of experimental animal research (Directive 10/63/EU, 2010, on the protection of animals used for scientific purposes).

Related to the 3Rs, there is now a guideline developed and accepted by many scientific journals, the ARRIVE (Animal Research Reporting of In Vivo Experiments) guidelines; next will be a guideline for planning animal experiments, the PREPARE (Planning Research and Experimental Procedures on Animals: Recommendations for Excellence) guidelines. These developments, directly or indirectly, aim to enhance and overview animal welfare in experiments, and compliance with the principles of the 3Rs is a condition-sine-qua-non: the 3Rs will evolve from a fixed descriptor to a moving document.

Noteworthy, considering discovery and development of medicinal products, regulatory agencies are nowadays not giving instructions on distinct animal models to be used in nonclinical testing of products. This aside, there are differences between agencies in different continents in accepting experimental animal data; the FDA in the USA is more strict than EMA in Europe regarding the need for, e.g., data from models in large animals in the investigational new drug documentation.

Finally, in the discovery and development of new medicinal products, there are shifts in types of drugs that affect the 3Rs. Most drugs developed thus far are extraction-based biological compounds or chemistry-based compounds, which generally show similar efficacy-safety effects in different animal species: for these types of drugs a broad spectrum of regulatory testing has been developed (see ICH, The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use), with separate testing for efficacy and safety in animals.

This huge spectrum of testing does not apply for the focus of medicines today, i.e., biologicals, cell therapy products and gene therapy products. Testing in animal models may require testing in disease models, enabling combined efficacy-safety studies, impacting the R of Reduction with a substantial decrease in the need for animals. Also, for most of these medicines there is species incompatibility, which can differ between efficacy and safety targets; hence there is no possibility for testing in animals, or only animals with an appropriate genetic modification.

Are the 3Rs still an important guideline for animal research today? Why?

HS: Absolutely. As outlined above, we are in the beginning of major education programs all over the world to implement 3Rs in experimental animal research. At the moment, the 3Rs are not a guideline but a principle, and animal research should be in compliance with these principles. The general public has increasing attention for experimental animal research, which is understandable in view of animal welfare, and this requires proper education. Compliance with 3Rs is a main factor to implement and maintain the highest quality of animal research, with proper consideration of animal welfare aspects.

Between 3Rs is a Q&A series created by the Charles River Laboratories’ Eureka blog and ALN Magazine to highlight the importance of the 3Rs—replacement, reduction, and refinement—as guidelines for ethical animal use in biomedical research. If you are interested in being a part of the series, contact or