Ventilation and gas exchange before and after voluntary static surface breath-holds in clinically healthy bottlenose dolphins, Tursiops truncatus [RESEARCH ARTICLE]

A. Fahlman, M. Brodsky, S. Miedler, S. Dennison, M. Ivancic, G. Levine, J. Rocho-Levine, M. Manley, J. Rocabert, and A. Borque Espinosa We measured respiratory flow (V), breathing frequency (fR), tidal volume (VT), breath durations, and end-expired O2 content in bottlenose dolphins (Tursiops truncatus) before and after static surface breath-holds ranging from 34 to 292 s. There was considerable variation in the end-expired O2, tidal volume VT, and fR following a breath-hold. The analysis suggests that the dolphins attempt to minimize recovery following a dive by altering VT, and fR to rapidly restore the O2 stores. For the first breath following a surface breath-hold, the end-expired O2 decreased with dive duration, while VT, and fR increased. Throughout the recovery, end-expired O2 increased while the respiratory effort (VT, fR) decreased. We propose that the dolphins alter respiratory effort following a breath-hold according to the reduction in end-expired O2 levels, allowing almost complete recovery after 1.2 min.

Source: Journal of Experimental Biology - February 13, 2019 Category: Biology Authors: Fahlman, A., Brodsky, M., Miedler, S., Dennison, S., Ivancic, M., Levine, G., Rocho-Levine, J., Manley, M., Rocabert, J., Borque Espinosa, A. Tags: RESEARCH ARTICLE Source Type: research