Annual report animal testing 2020: Majority of tests conducted on fish

Published on
July 15, 2021

Wageningen University & Research conducted a total of 61,335 tests on animals in 2020, 21.2 per cent fewer than in 2019, when 77,788 tests were performed. The discrepancies are related to large-scale, multi-year research programmes.

The majority of the tests involving animals at WUR were conducted within studies related to the protection of species (the largest portion involved monitoring fish stock) and applied research on animal welfare and health. Other research objectives were: statutory research tasks, batch potency testing in particular (testing the efficacy of medicine batches), and research on bioaccumulation (the accumulation of hazardous substances in living organisms), and fundamental research (related to the immune system in particular). A small portion of the total number of tests on animals (2 per cent) was done for educational purposes.

Animal species

Just under three-quarters (72.2 per cent) of all tests on animals at WUR involved fish. Primarily within the statutory research task of monitoring fish stock. Chickens came second with 14.2 per cent, followed by cattle (4 per cent). The research on these species was mainly related to animal welfare.


The majority of the animal tests (68 per cent) conducted by WUR lead to mild discomfort for the animals involved. Actions and procedures that have no significant impact on the animals’ wellbeing are considered as causing mild discomfort. Examples of mild discomfort include taking single blood samples or separating group animals such as mice and chickens from their social group for a short period.

One-quarter of the animal tests cause moderate discomfort. This applies if an animal suffers moderate discomfort for a short period, or mild discomfort for a longer period. Examples of activities that cause moderate discomfort include the more frequent taking of blood samples and separating social animals for periods of days or several weeks (depending on the species).

Replace, Reduce, Refine: the 3Rs

WUR actively works to implement the so-called 3Rs: Replacing, Reducing and Refining animal testing. Replacing refers to the development of alternative research methods that render the use of animals unnecessary. Reducing means literally using fewer animals for testing. In refining, the research methods are adjusted to reduce the discomfort they cause the animals.

Innovation programme Next Level Animal Sciences

Wageningen University & Research invests in the 3Rs through, among others, the Next Level Animal Sciences innovation programme. Within this programme, for which WUR provides 12 million euros in funding, WUR researchers collaborate with partners to develop and refine new research methods and technologies within the domain of animal sciences: sensor technology, big data and organoids. These innovative methodologies present an alternative for the more invasive research methods in animal testing. These methodologies are expected to enable scientists to take significant strides in the coming decades to understand, monitor and enhance animal (and human) health, resilience and wellbeing.