One of the characteristics that make zebrafish a fantastic model for research is that they spawn…a lot. A healthy female zebrafish can lay upwards of 1,000 eggs each week. By comparison, the mouse, another species widely used in research, may have a single 12-pup litter each month.
Sometimes, though, that isn’t enough. A researcher screening a library of chemicals for potential drugs, for instance, might need tens of thousands of zebrafish embryos, all at the same developmental stage, to have statistically meaningful results.
They’re small, they’re transparent, and they breed at an amazing rate. They may hold the key to understanding the genetics of many human diseases. And they may help scientists discover new drugs – quicker and cheaper. Oh, and they’re fish.
The zebrafish (Danio rerio to the taxonomists) is a striped tropical fish, no longer than your pinky finger, that looks like it would be more at home in someone’s aquarium than in a laboratory. But for several reasons, zebrafish are powerful organisms for stem cell, developmental, and genetic research:
Despite our distance from zebrafish on the evolutionary tree, they’re surprisingly similar to us from a genetic standpoint.
Because of their small size, they can be housed at high densities.
Compared to other model organisms like mice, they’re relatively inexpensive to care for.
An adult female zebrafish can lay 300 eggs each week. By comparison, a mouse might have a single 12-pup litter each month.
Their skin is permeable, so they can absorb drugs directly from the water of their tank.
Zebrafish embryos are transparent, offering a window into their bodies; some lines, like Casper, remain transparent through adulthood. …