Consistent changes in muscle metabolism underlie dive performance across multiple lineages of diving ducks

Schell, E. R., McCracken, K. G., Scott, G. R., White, J., Lavretsky, P. and Dawson, N. J. (2023) Consistent changes in muscle metabolism underlie dive performance across multiple lineages of diving ducks. Proceedings of the Royal Society B: Biological Sciences, 290(2007), 20231466. (doi: 10.1098/rspb.2023.1466) (PMID:37752838) (PMCID:PMC10523079)

Abstract

Diving animals must sustain high activity with limited O₂ stores to successfully capture prey. Studies suggest that increasing body O₂ stores supports breath-hold diving, but less is known about metabolic specializations that underlie underwater locomotion. We measured maximal activities of 10 key enzymes in locomotory muscles (gastrocnemius and pectoralis) to identify biochemical changes associated with diving in pathways of oxidative and substrate-level phosphorylation and compared them across three groups of ducks—the longest diving sea ducks (eight spp.), the mid-tier diving pochards (three spp.) and the non-diving dabblers (five spp.). Relative to dabblers, both diving groups had increased activities of succinate dehydrogenase and cytochrome c oxidase, and sea ducks further showed increases in citrate synthase (CS) and hydroxyacyl-CoA dehydrogenase (HOAD). Both diving groups had relative decreases in capacity for anaerobic metabolism (lower ratio of lactate dehydrogenase to CS), with sea ducks also showing a greater capacity for oxidative phosphorylation and lipid oxidation (lower ratio of pyruvate kinase to CS, higher ratio of HOAD to hexokinase). These data suggest that the locomotory muscles of diving ducks are specialized for sustaining high rates of aerobic metabolism, emphasizing the importance of body O₂ stores for dive performance in these species.

• Item Type: Articles
• Additional Information: This work was supported by funds from the Kushlan Endowment for Waterbird Biology and Conservation at the University of Miami and the University of Miami Department of Biology. N.J.D. was also supported by an ISSF ECR Catalyst Grant (#310331–01/Wellcome Trust), a NSERC postdoctoral fellowship (NSERC PDF-488166) and an Advanced Grant from the European Research Council (ERC; no. 834653) to Neil B. Metcalfe. G.R.S. is supported by the Canada Research Chairs program.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Schell, Miss Elizabeth and Dawson, Dr Neal
• Authors: Schell, E. R., McCracken, K. G., Scott, G. R., White, J., Lavretsky, P., and Dawson, N. J.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Proceedings of the Royal Society B: Biological Sciences
• Publisher: Royal Society of London
• ISSN: 0962-8452
• ISSN (Online): 1471-2954
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Proceedings of the Royal Society B: Biological Sciences 290(2007):20231466
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
310331		Born Old: Developing a method to examine the link between aging and mitochondrial dysfunction in the oocytes of oviparous species	Neal Dawson	Wellcome Trust (WELLCOTR)	N/A	Institute of Biodiversity, Animal Health and Comparative Medicine
305090		MITOWILD	Neil Metcalfe	European Commission (EC)	834653	Institute of Biodiversity, Animal Health and Comparative Medicine