Metrics, scales, and correlates of intraspecific variation in hypoxia tolerance in fishes

Frontiers in Fish Science, Journal Year: 2025, Volume and Issue: 3

Published: March 19, 2025

The extent of aquatic hypoxia (low dissolved oxygen) has increased in recent times and now threatens habitats worldwide. Here, we review intraspecific variation tolerance fish on various scales: geographic among populations; genetic strains; due to laboratory acclimation; individuals coming from a given population having similar exposure history. Metrics include the oxygen level below which costs maintenance can no longer be met by uptake environment; time or at surface respiration is conducted; levels lose ability for coordinated movement. There great diversity range its association with potential underlying morphological, physiological, correlates. We advocate greater standardization experimental design, enhanced data reporting, development validation new metrics tolerance. With understanding tolerance, it might possible predict populations, strains, will fare better during hypoxic episodes; mitigate effects low fishes; design breeding protocols enhance fishes.

Language: Английский

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Transcriptomic signatures associated with developmental transitions in the gill of lake sturgeon (Acipenser fulvescens)

Comparative Biochemistry and Physiology Part D Genomics and Proteomics, Journal Year: 2025, Volume and Issue: unknown, P. 101505 - 101505

Published: April 1, 2025

Language: Английский

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Branchial localization of acid (A‐type) and base (B‐type) excreting ionocytes in Amazonian stenohaline freshwater Potamotrygon ray

Journal of Fish Biology, Journal Year: 2025, Volume and Issue: unknown

Published: May 9, 2025

Abstract The branchial epithelium of Potamotrygon —a member the only strictly freshwater elasmobranch family Potamotrygonidae—was observed via immunohistochemistry, and two distinct forms ionocytes were identified. acid (A‐type) base (B‐type) secreting cells with respective basolateral–apical localizations Na + /K ‐ATPase–Na /H exchanger 3 in A‐type V‐type H ‐ATPase–pendrin Cl − /HCO B‐type detected morphometric changes response to acid–base disturbances (3 mmol/kg body mass [HCl] or load [NaHCO ] by intraperitoneal injection) characterized. found follicular clusters interlamellar region, while individually both filament lamellar epithelia. Lamellar more abundant larger, greater fluorescence than their counterparts. responded increasing number showed a peripheral ‐ATPase distribution, indicative activation translocation basolateral membrane labyrinth. decreased size load. In contrast, no compared sham group. Together, these results indicate that stenohaline rays have ion uptake allow them effectively ionoregulate under challenging ion‐poor water conditions Amazon.

Language: Английский

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Fick’s Diffusion Laws and Scaling of the Gill Surface Area and Oxygen Uptake in Fish

Fishes, Journal Year: 2025, Volume and Issue: 10(5), P. 233 - 233

Published: May 16, 2025

The oxygen consumption of adult fish (Q) is proportional to their body weight (W) raised a power, estimated as the slope (dQ) linear regression log(Q) vs. log(W). Similarly, gill surface area (GSA) W power dG, also via log-log area. Moreover, because Fick’s laws diffusion, dQ should be at least similar dG. Recently, claim has been made that non-zero differences between and dG invalidate Gill-Oxygen Limitation Theory (GOLT), which suggests O2 supplied by gills growing with <1 limits growth older larger fish. We show here, based on 33 pairs in species other information (i) while individual are observed several cases, there no significant overall difference across estimates (ii) large primarily due ontogenetic changes scaling (OCS), likely gills’ water–blood (or ‘diffusion’) distance and, well, multiple sources experimental variability potential errors, leading outliers random differences.

Language: Английский

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The hypoxia adaptation strategy of the big-belly seahorses (Hippocampus abdominalis) with tuft gills

Aquaculture Reports, Journal Year: 2024, Volume and Issue: 40, P. 102544 - 102544

Published: Dec. 17, 2024

Language: Английский

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