Serum antioxidant levels in wild birds vary in relation to diet, season, life history strategy, and species
- 9 August 2009
- journal article
- research article
- Published by Springer Science and Business Media LLC in Oecologia
- Vol. 161 (4), 673-683
- https://doi.org/10.1007/s00442-009-1423-9
Abstract
Micronutrient antioxidants are thought to be generally important for health in many animals, but factors determining levels in individuals and species are not well understood. Diet and season are obvious environmental variables that might predict the degree to which species can accumulate such nutrients. We analyzed antioxidant levels [Trolox-equivalent antioxidant capacity (TEAC), uric acid (UA), vitamin E, and four carotenoids] in 95 bird species and compared these to species-level data on diet from the literature. Using compositional principal components analysis, we identified two main axes of diet variation: invertebrate consumption and seed-to-fruit ratio. We then examined associations between diet axes and antioxidant measures, with and without control for life-history variation and phylogeny. We also analyzed a subset of 13 species for which we had data on seasonality of antioxidant levels and diet, assessing the variance in antioxidant levels explained by seasonality, diet, and species. Unsurprisingly, there were strong associations between antioxidant levels and diet. TEAC and UA concentration were consistently positively associated with invertebrate consumption and seed-to-fruit ratio, and carotenoid concentrations (e.g. zeaxanthin and β-carotene) were negatively associated with invertebrate consumption. However, vitamin E was not associated with diet as measured here. Importantly, there is much variation in antioxidants that is not explained by diet, and we are able to identify diet-independent effects of species, season/breeding stage, and life history on antioxidant levels. Circulating antioxidant concentrations within and across species can therefore be viewed as a function of multiple factors, including but not limited to diet, and antioxidant metabolism appears to differ across species and seasons irrespective of diet.Keywords
This publication has 46 references indexed in Scilit:
- Interspecific Associations between Circulating Antioxidant Levels and Life‐History Variation in BirdsThe American Naturalist, 2008
- Stress, Metabolism, and Antioxidants in Two Wild Passerine Bird SpeciesPhysiological and Biochemical Zoology, 2008
- Oxidative stress does not influence carotenoid mobilization and plumage pigmentationProceedings. Biological sciences, 2007
- Carotenoid availability does not limit the capability of nestling kestrels (Falco tinnunculus) to cope with oxidative stressJournal of Experimental Biology, 2007
- Partial Synthesis of (3R,6‘R)-α-Cryptoxanthin and (3R)-β-Cryptoxanthin from (3R,3‘R,6‘R)-LuteinJournal of Natural Products, 2007
- Interspecific variation in the use of carotenoid‐based coloration in birds: diet, life history and phylogenyJournal of Evolutionary Biology, 2005
- The effects of vitamin C supplementation on serum concentrations of uric acid: Results of a randomized controlled trialArthritis & Rheumatism, 2005
- The physiological costs of being colourful: nutritional control of carotenoid utilization in the American goldfinch, Carduelis tristisAnimal Behaviour, 2005
- Antioxidant status and nonspecific immune responses in rainbow trout (Oncorhynchus mykiss) fed two levels of vitamin E along with three lipid sourcesAquaculture, 2004
- Expression pattern and localization of β,β-carotene 15,15′-dioxygenase in different tissuesBiochemical Journal, 2001