Vervangen, verminderen en verfijnen: De drie Vā€™s

Replace, reduce and refine

WUR actively seeks to develop and implement alternatives to animal testing. This could be an alternative research model or an alternative research technique that makes the use of animal testing unnecessary (replace), that reduces the number of test animals needed (reduce), and/or ensures that the research methods cause less suffering to the animals (refine).

An alternative research model or technique can mean that the use of test animals is delayed until the final, decisive and/or evaluative phase of the research project, or that it is no longer needed at all. In some cases, alternative research methods produce better results and are cheaper than animal tests.

1. Replace

An animal test is fully or partially replaced with computer models or laboratory tests on tissues. In some cases, so much information can be obtained in this way that fewer or no test animals are needed in the research project.

2. Reduce

The aim is to obtain a reliable research result using as few test animals as possible. Statistical techniques are very important for achieving this. Improved research methods or test conditions can reduce unintended variants, allowing a reliable result to be obtained using fewer animals.

3. Refine

There are different ways of refining animal experiments. The welfare of test animals can be improved by adapting housing, introducing remote monitoring (telemetry) and/ or improving laboratory techniques so that less material (e.g. blood) is required. It is also possible to adapt protocols and procedures to improve the quality of animal-animal and human-animal relationships (e.g. between the test animal and its carer). Another way of improving the welfare of the test animal is to introduce measures that reduce boredom and prevent stress.

Examples of alternatives to animal testing

For toxicological testing and the diagnosis of infectious diseases, more and more animal experiments are being replaced with alternatives, in the form of chemical and biochemical tests.


Using organoids ā€“ small models of organs made from organ cells ā€“ it is possible to conduct tests on human or animal cell tissue. Organoids cannot replace test animals entirely, but they offer plenty of opportunities for reducing the number of test animals required, especially in preliminary studies.

DNA analysis

Alternatives to animal testing are also available for wild animals, for example to investigate the prevalence of a certain species in an area. Whereas researchers used to have to catch animals, we can now obtain information such as individual identification, sex and family relationships by analysing the DNA in the faeces.

Reduce suffering through refinement

Refinement is about optimising the welfare of animals and reducing their suffering. This concerns not just the animal experiments, but the whole process, including transport and the acclimatisation period.


Multifunctional test animal housing is available at WUR, in which the housing system is adapted to the specific needs of each type of animal. The aim is to provide each animal with the opportunity to display natural behaviour as much as possible, despite the demands of the research procedures.

For example, litter and other forms of enrichment are added. Pigs will use litter on a daily basis to make a place to rest and sleep. Rodents are provided with shelters and nesting material, and ferrets with hammocks. Brushes, water bowls and games may also be added. For chickens, bells and mirrors may be hung up, and dogs are provided with an obstacle course to encourage physical activity.

Group housing

Wherever possible, test animals are housed as a group, with extra attention paid to acclimatisation, socialisation and training.

Such measures help prevent chronic stress amongst test animals. We are learning more and more about the effects of chronic stress on the immune system and well-being of animals. Preventing chronic stress not only improves animal welfare, but also the quality of the research. The animal carers at WUR are trained to monitor animal welfare.