Marker-dependent associations among oxidative stress, growth and survival during early life in a wild mammal

Christensen, L. L. , Selman, C. , Blount, J. D., Pilkington, J. G., Watt, K. A., Pemberton, J. M., Reid, J. and Nussey, D. H. (2016) Marker-dependent associations among oxidative stress, growth and survival during early life in a wild mammal. Proceedings of the Royal Society of London Series B: Biological Sciences, 283(1840), 20161407. (doi: 10.1098/rspb.2016.1407) (PMID:9729611) (PMCID:PMC98936)

Abstract

Oxidative stress (OS) is hypothesized to be a key physiological mechanism mediating life-history trade-offs, but evidence from wild populations experiencing natural environmental variation is limited. We tested the hypotheses that increased early life growth rate increases OS, and that increased OS reduces first-winter survival, in wild Soay sheep (Ovis aries) lambs. We measured growth rate and first-winter survival for four consecutive cohorts, and measured two markers of oxidative damage (malondialdehyde (MDA), protein carbonyls (PC)) and two markers of antioxidant (AOX) protection (total AOX capacity (TAC), superoxide dismutase (SOD)) from blood samples. Faster lamb growth was weakly associated with increased MDA, but not associated with variation in the other three markers. Lambs with higher SOD activity were more likely to survive their first winter, as were male but not female lambs with lower PC concentrations. Survival did not vary with MDA or total TAC. Key predictions relating OS to growth and survival were therefore supported in some OS markers, but not others. This suggests that different markers capture different aspects of the complex relationships between individual oxidative state, physiology and fitness, and that overarching hypotheses relating OS to life-history variation cannot be supported or refuted by studying individual markers.

• Item Type: Articles
• Additional Information: L.L.C. was supported by a BBSRC EASTBIO Doctoral Training Partnership studentship; D.H.N. by a BBSRC David Phillips fellowship and J.D.B. by a Royal Society University Research Fellowship. Field data collection on the St Kilda Soay sheep project has been supported over the past 30 years by responsive mode NERC grants to J.M.P. and others.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Selman, Professor Colin
• Authors: Christensen, L. L., Selman, C., Blount, J. D., Pilkington, J. G., Watt, K. A., Pemberton, J. M., Reid, J., and Nussey, D. H.
• Subjects: ?? Soay sheep ??; ?? antioxidants ??; ?? early life fitness ??; ?? life-history trade-offs ??; ?? oxidative damage ??; ?? plasma ??
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Proceedings of the Royal Society of London Series B: Biological Sciences
• Publisher: The Royal Society
• ISSN: 0962-8452
• ISSN (Online): 1471-2954
• Published Online: 12 October 2016
• Copyright Holders: Copyright © 2016 The Authors
• First Published: First published in Proceedings of the Royal Society of London Series B: Biological Sciences 283(1840):20161407
• Publisher Policy: Reproduced under a Creative Commons License