Zebrafish are making a splash

Zebrafish, named for their black and white stripes, are helping us answer some of the big questions about MS. Dr Carl Tucker looks after tens of thousands of zebrafish at the University of Edinburgh.

What makes zebrafish so special?

Zebrafish are pretty unique. At five days old, a zebrafish embryo is only 5mm long but is practically a complete fish with all its major organs. Unlike humans, they can regenerate all their organs - even the heart!

But for scientists, the best thing about zebrafish is that the embryos are almost completely transparent. So you see all the processes going on inside their bodies.

How can zebrafish help people with MS?

It might seem surprising that fish can help us understand human conditions like MS, but we actually share approximately 70% of our DNA with zebrafish.

Although we find out lots of important information from looking at individual cells in a dish, you need a living organism to know how all these cells interact.

I work closely with Professor David Lyons, a researcher based here at the University of Edinburgh. He’s doing brilliant research on zebrafish and MS. And our zebrafish are also used to study all sorts of other conditions, like heart disease and cancer.

How do you take care of the zebrafish?

We take the welfare of our fish very seriously. In fact, at Edinburgh there’s an entire department dedicated to the care of research animals.

Our zebrafish are fed three times a day with a special balanced diet, and the water quality is constantly monitored to make sure it’s ideal at all times.

Under UK law all experimental procedures must assess the possible harms to an animal. The vast majority of procedures are considered mild - this means the impact on the fish is minimal. If it’s possible that pain may occur, we let the fish swim about in a bath of a liquid containing anaesthetic, which they take in through their gills.

Can anyone use zebrafish for research?

No, the UK’s laws around animal research are among the toughest in the world. Scientists who use animals in their research do a lot of training and are required to get lots of different licenses. The government can do inspections and if a lab is found to be violating the law, it can have very serious consequences and the research can be stopped.

Do you enjoy working with zebrafish?

Absolutely. I love my job, because we’re working to help people living with painful and debilitating conditions.

I know some people find it peculiar that fish are used for medical research, but if we want to stop conditions like MS, we need animals to help us understand them.

Read our policy on the use of animals in research