Animal sciences and health

In the research theme ‘Animal Sciences and Health’, we work with various animal species to gain insights into fundamental biological processes in both animals and humans.

Research with zebrafish

The zebrafish is an important model species. Zebrafish are measuring between three and four cm in length and are commonly found in tropical waters and aquariums. Despite being more distantly related to humans than mammals, research on zebrafish contributes valuable fundamental biological knowledge, offering insights into diseases in humans.

Our research involving zebrafish encompasses studies conducted on embryos, larvae, and adult animals. Notably, research on embryos and larvae (up to five days old) is not subject to registration under the Dutch Animals Experiments Act. However, we explicitly mention this aspect as it constitutes a significant portion of our research. The use of adult animals (older than five days) is limited in our research activities.

Zebrafish as a model for human diseases

Zebrafish are employed in our research as a model for human diseases. This provides us with valuable insights into the biological processes associated with various conditions, including cancer, and infectious and inflammatory diseases. Additionally we conduct fundamental research on the development of both animals and humans to gain insights into the genetic and environmental factors that contribute to their growth and maturation. The knowledge acquired through this research enables us to explore new avenues in drug development and discover innovative treatments for diseases.

Zebrafish a as a model for animal behaviour

We also conduct research that directly benefits animals. For instance, adult zebrafish are used to investigate the effects of human-induced increases in underwater noise on the behaviour and well-being of fish.

Zebrafish to advance our research

‘By researching the initial stages of drug development, we can design much more specific experiments for subsequent studies. This allows experiments with larvae to replace follow-up studies in mammals and enable us to refine and enhance the design of our studies.’

We further explore novel screening methods for drugs and other compounds to assess whether zebrafish can serve as a potential alternative to mice and other rodents. Our primary focus is on examining the suitability of zebrafish embryos and larvae for these purposes. These developmental stages have less developed nervous systems, resulting in reduced or minimal pain and stress, making them a preferable alternative to experiments involving older zebrafish or rodents.

Additionally, our research delves into refining animal experiment methodologies and optimising the assessment of targeted outcomes and how to optimise testing for your specific research goals. This approach allows us to conduct more focused research, minimizing the use of laboratory animals.

As an example, you can read about the research conducted by pharmaceutical scientist Rob van Wijk.

Research with birds

At Leiden University, we mainly work with zebra finches. These small birds are commonly kept as pets.

Behaviour and language development

Researchers use zebra finches as a model species for studying bird behaviour. This includes research into aspects such as mate choice in birds, as well as how birds learn, communicate, and process information. This research also contributes to a better understanding of human cognitive processes, particularly language development.

For instance, biologist Katharina Riebel used a high-tech robotic bird to study how young zebra finches learn to sing. Read more: Robo-bird teaches young zebra finches to sing.

Biologist Michelle Spierings explores, through studying birds, the origins and development of our ability for speech and music. Read more: Veni-grant for Michelle Spierings: ‘Do birds hear tick-tock too, or tock-tick?’

Birds in the Wild

In addition to research conducted in our facilities, we also engage in field research with birds. Through this, we investigate the effects of increasing urban and traffic noise on the song and behaviour of birds. Additionally, we explore the role of song in the mate selection and territorial behaviour of birds.

Research with other animals

In addition to our primary areas of focus, we conduct occasional research on various other animal species, including different vertebrates such as snakes and amphibians. We study snakes to gain insights into evolution and explore potential applications for their venom. Our research on amphibians is centered on enhancing our understanding of developmental processes and evolution.

We use invertebrates for both fundamental and applied research. This primarily involves insects, but we also investigate squids. Squids are commonly employed as models due to their highly developed nervous systems, making them well-characterised subjects. The focus of this research is on the interaction between squids and the light-emitting bacteria in the squid’s light organ. Our aim is to comprehend, at a molecular level, the workings of this unique symbiosis.