Thermal effects on red muscle contractile performance in deep-diving, large-bodied fishes
| Autor: | Scott A. Aalbers, Ashley A. Stoehr, Jeanine M. Donley, Douglas A. Syme, Diego Bernal, Chugey A. Sepulveda |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Physiology
Aquatic Science Biochemistry 03 medical and health sciences Deep diving Alopias superciliosus Animals Gladius Muscle Skeletal 030304 developmental biology 0303 health sciences biology Swordfish Fishes Temperature Pelagic zone 04 agricultural and veterinary sciences General Medicine biology.organism_classification Fishery Muscle Fibers Slow-Twitch Ectotherm Work loop 040102 fisheries 0401 agriculture forestry and fisheries Thermocline Muscle Contraction |
| Zdroj: | Fish physiology and biochemistry. 46(5) |
| ISSN: | 1573-5168 |
| Popis: | Bigeye thresher sharks (Alopias superciliosus) and swordfish (Xiphias gladius) are large, pelagic fishes, which make long-duration, diurnal foraging dives from warm, surface waters (18–24 °C) to cold waters beneath the thermocline (5–10 °C). In bigeye thresher sharks, the subcutaneous position of the red, aerobic swimming muscles (RM) suggests that RM temperature mirrors ambient during dives (i.e., ectothermy). In swordfish, the RM is closer to the vertebrae and its associated with vascular counter-current heat exchangers that maintain RM temperature above ambient (i.e., RM endothermy). Here, we sought to determine how exposure to a wide range of ambient temperatures (8, 16, 24 °C) impacted peak power output and optimum cycle (i.e., tailbeat) frequency (0.25, 0.5, 1 Hz) in RM isolated from both species. Bigeye thresher shark RM did not produce substantial power at high cycle frequencies, even at high temperatures; but it did produce relatively high power at slow cycle frequencies regardless of temperature. Swordfish RM produced more power when operating at a combination of fast cycle frequencies and higher temperatures. This suggests that swordfish RM benefits considerably more from warming than bigeye thresher shark RM, while the RM of both species was able to produce power at cold temperatures and slow cycle frequencies. Despite different thermal strategies (i.e., ectothermy vs. RM endothermy), the ability of the RM to power sustained swimming during foraging-related search behaviors may contribute to the unique ability of these fishes to successfully exploit food resources in deep, cold water. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink