A 3D-printed and freely available device to measure the zebrafish optokinetic response before and after injury

Zebrafish have eyes similar to humans, making them a beneficial model organism for studying vision. However, zebrafish are different in that they can regenerate their optic nerve after injury, which most other animals cannot. Measuring vision in people who have communicative ability is achieved using eye charts. Because fish cannot use an eye chart, we utilize the optokinetic response (OKR) that is present in virtually all vertebrates to determine if a zebrafish has eyesight. To this end, we have developed an inexpensive OKR setup that uses 3D-printed and off-the-shelf parts. This setup has been designed and used by undergraduate researchers and is also scalable to a classroom lab setup. We demonstrate that this setup is fully functional for assessing OKR, and we use it to illustrate the return of the OKR following optic nerve injury in adult zebrafish.