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Fish species in animal experimentation


Admission requirements

MSc Biology


The course aims to provide knowledge that is essential for understanding the humane use and care of fish as laboratory animals and for the quality of research using fish species. This course is obligatory before starting an internship that involves handling or experimental use of fish species.

One part of the course is a general introduction about the specific responsibilities (both legal and moral) of a scientist, as the central person in the design and conduct of animal experiments, for the management of the study and the welfare of the animals used. Legal and ethical frameworks for the use of laboratory animals will be discussed. Common laboratory species will be introduced, including some features of anatomy and physiology. Information required for ethical review, the choice of animal species, the origin of the animals, animal housing and husbandry, environmental conditions, humane endpoints, whether or not induction of a disease is needed, and the methods for anesthesia or humane killing are discussed.

This general introduction to laboratory animal science is complemented by a specific theoretical and practical program on the use of fish as experimental animals. The program will cover different research areas using fish species, including, biomedical research, developmental research, behavioral research, ecotoxicology, aquaculture-related research and wildlife studies. An overview will be given about commonly used fish species in these research areas, and, in particular, a strong emphasis will be placed on the use of zebrafish for biomedical research.

In a series of lectures, the course participants will be introduced to fish development, anatomy and physiology, the immune system, disease modelling and drug screening, recognition of discomfort, stress and pain, disease symptoms and health monitoring, anesthesia/euthanasia methods, genetic modification, behavioral research, experiments with fish in the wild. Finally, an introduction will be given about zebrafish facility management and husbandry.

The practical program takes place at the Zebrafish Facility of the Faculty of Science and consists of a introduction at the facility and several practical assignments related to observing and handling of zebrafish.

Course objectives

After completion of the course, students can:

  • reproduce and discuss the ethical and legal considerations that apply to experiments on fish in the laboratory or in the wild.

  • categorize and evaluate the levels of discomfort, stress and pain in fish experiments.

  • name procedures for analgesia, anesthesia and euthanasia and assess when to apply humane endpoints.

  • explain the purpose of the essential requirements of a laboratory fish facility and the procedures for water quality control, husbandry and handling of fish.

  • recognize and describe common symptoms of fish disease and explain the procedures for disease prevention and health monitoring.

  • reproduce the basic characteristics of fish development, anatomy, physiology and the immune system and can explain how these features affect the results of an animal study.

  • name the commonly used fish species in animal experimentation and give examples of their use in behavioral research, biomedical research, toxicology, aquaculture research and research in the wild.

  • explain the basic techniques that are used for genetic modification in fish species.


12 February 2024 – 28 February 2024
12-23 February 2024: General introduction to animal experimentation, species-specific fish course theory and practical.
This is a 2 week program with lectures, group assignments and practical assignments.
28 February 2024: exam.

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For more information, please watch the instructional video or visit the "help-page" within MyTimetable. Note that Joint Degree students from Leiden/Delft will need to merge their two separate timetables into one. A video tutorial is available to guide you through the merging process.

Mode of instruction

The course consists of a lecture program given by various teachers, written group assignments and practical assignments in the zebrafish facility.

Assessment method

The final grade is based on a written examination (75%) and a written assignment (25%). Practical program is pass/fail.
Attendance to all lectures and the practical is compulsory in order to receive the certificate.

Reading list


From the academic year 2022-2023 on every student has to register for courses with the new enrollment tool MyStudyMap. There are two registration periods per year: registration for the fall semester opens in July and registration for the spring semester opens in December. Please see this page for more information.

Please note that it is compulsory to both preregister and confirm your participation for every exam and retake. Not being registered for a course means that you are not allowed to participate in the final exam of the course. Confirming your exam participation is possible until ten days before the exam.

Extensive FAQ's on MyStudymap can be found here.


Daily coordinator for questions and administrative issues: G.C. van der Velden MSc


The maximum number of participants is limited to 40 students. Students starting a internship that involves handling or experimental use of fish species have priority.