Intubation-based anesthesia for long-term time-lapse imaging of adult zebrafish

Zebrafish possess the remarkable ability to regenerate a vast variety of tissues, even as adults. However, direct imaging of regenerative processes in adult zebrafish remains challenging because of the lack of suitable anesthesia protocols. Here we present a description of an intubation-based anesthesia procedure that we developed to enable us to image regenerating zebrafish fins and which can be used to continuously anesthetize adult zebrafish for up to 2 d. Fish are immobilized in an imaging chamber followed by oral intubation. Subsequent delivery of anesthetic-containing water is achieved via a peristaltic pump. The setup of the system will take similar to 90 min for two adult zebrafish, and it requires only a little previous experience of working with zebrafish. Our protocol will enable the imaging of regenerative processes in the fin and other tissues, and the investigation of processes that require long-term anesthesia, such as immune responses and surgical procedures.