Intertidal triplefin fishes have a lower critical oxygen tension (Pcrit), higher maximal aerobic capacity, and higher tissue glycogen stores than their subtidal counterparts
Autor: | Andreas Kunzmann, Lisa Wallace, Neill A. Herbert, Anthony J. R. Hickey, Tristan. J. McArley |
---|---|
Rok vydání: | 2019 |
Předmět: |
030110 physiology
0106 biological sciences 0301 basic medicine Gill Forsterygion Physiology Intertidal zone 010603 evolutionary biology 01 natural sciences Biochemistry 03 medical and health sciences chemistry.chemical_compound Endocrinology Animal science Ecology Evolution Behavior and Systematics geography geography.geographical_feature_category Glycogen biology VO2 max Hypoxia (environmental) biology.organism_classification Oxygen tension chemistry Animal Science and Zoology Tide pool |
Zdroj: | Journal of Comparative Physiology B. 189:399-411 |
ISSN: | 1432-136X 0174-1578 |
DOI: | 10.1007/s00360-019-01216-w |
Popis: | Decreased oxygen (O2) availability (hypoxia) is common in rock pools and challenges the aerobic metabolism of fishes living in these habitats. In this study, the critical O2 tension (Pcrit), a whole animal measure of the aerobic contribution to hypoxia tolerance, was compared between four New Zealand triplefin fishes including an intertidal specialist (Bellapiscis medius), an occasional intertidal inhabitant (Forsterygion lapillum) and two exclusively subtidal species (F. varium and F. malcolmi). The intertidal species had lower Pcrit values than the subtidal species indicating traits to meet resting O2 demands at lower O2 tensions. While resting O2 demand (standard metabolic rate; SMR) did not show a major difference between species, the intertidal species had higher maximal rates of O2 consumption ($$ \dot{M}{\text{O}}_{{2,{ \hbox{max} }}} $$) and higher aerobic metabolic scope (MS). The high O2 extractive capacity of the intertidal species was associated with increased blood O2 carrying capacity (i.e., higher Hb concentration), in addition to higher mass-specific gill surface area and thinner gill secondary lamellae that collectively conveyed a higher capacity for O2 flux across the gills. The specialist intertidal species B. medius also had higher glycogen stores in both white muscle and brain tissues, suggesting a greater potential to generate ATP anaerobically and survive in rock pools with O2 tensions less than Pcrit. Overall, this study shows that the superior Pcrit of intertidal triplefin species is not linked to a minimisation of SMR, but is instead associated with an increased O2 extractive capacity of the cardiorespiratory system (i.e., $$ \dot{M}{\text{O}}_{{2,{ \hbox{max} }}} $$, MS, Hb and gill O2 flux). |
Databáze: | OpenAIRE |
Externí odkaz: |