Meeting Abstract
P3.164 Sunday, Jan. 6 Finding balance in an unstable world: the neural control and kinematics of larval zebrafish pectoral fins in response to roll BLIAMPTIS, J.P.*; HALE, M.E.; University of Chicago; University of Chicago jpbliamptis@gmail.com
While the pectoral fins of larval zebrafish (Danio rerio) beat regularly and in coordination with axial undulations during steady forward swimming, experimental work indicates that they do not serve a propulsive or stabilizing role in this behavior but appear to have a respiratory function, mixing fluid near the body. Beyond steady swimming, the question of whether larval pectoral fins are used in movement systems remains unanswered. As adult fish use pectoral fins in a diverse set of behaviors, including for stability, maneuvering, forward propulsion and braking, the pectoral fins of larval may also function in these contexts. We hypothesized that the fins are active in response to environmental perturbations that destabilize the animal, and we focused on their response to roll. We partially embedded larval zebrafish so that the fins were free to move and tipped the fish, generating roll to right and left side. As a control, we also moved the tank without roll. The fish reacted consistently with alternating pectoral fin movement in response to roll but not to non-roll movement. We compared fin kinematics between left and right side rolls and found no consistent difference in the pattern of fin movement associated with roll direction. To begin to understand how this response is neurologically controlled, we examined the role of the vestibular region in the response. We embedded zebrafish with cranial transections that either retained or eliminated vestibular input to the fin motor pool. When the vestibular system was ablated, the behavior was no longer observed indicating the presence of circuit connections between the vestibular nerve and fins. We have yet to determine the effect of pectoral fin movement on body roll but hypothesize that they generate force to correct for the perturbation.
