Carotenoid availability does not limit the capability of nestling kestrels (<i>Falco tinnunculus</i>) to cope with oxidative stress

Oxidative stress is the imbalance between the production of reactive species and antioxidants, which causes damage to lipids, proteins and DNA. Antioxidants, like vitamins and carotenoids, can limit oxidative damage and can therefore regulate the trade-off between growth, which is a period of high reactive species production, and self-maintenance. However, the role of carotenoids as antioxidants in vivo has been debated, and it has been suggested that carotenoidbased signals indicate the availability of non-pigmentary antioxidants (e.g. vitamins) that protect carotenoids from oxidation, known as the 'protection hypothesis'. To evaluate the importance of vitamins versus carotenoids as antioxidants during growth and to test the protection hypothesis, we supplemented nestling great tits, Parus major, 3, 5 and 7 days after hatching with a single dose of carotenoids and/or vitamins in a 2×2 full-factorial design. We subsequently measured body condition, antioxidant capacity, oxidative damage, fledging success and plumage reflectance. Vitamins enhanced antioxidant capacity, but did not affect oxidative damage. Vitamin-treated nestlings had higher growth rates and higher probability of fledging. In contrast, carotenoids did not affect any of these traits. Furthermore, carotenoid-based colouration increased over the breeding season in nestlings that received vitamins only. This study shows that vitamins are limiting for growth rate and fledging success, and suggests that vitamins could regulate the trade-off between growth and selfmaintenance in favour of the former. Moreover, our results are consistent with the idea that carotenoids are minor antioxidants in birds, but they do not support the protection hypothesis.

Section: Research Articlementioning

confidence: 99%

Differential effects of vitamins E and C and carotenoids on growth, resistance to oxidative stress, fledging success and plumage colouration in wild great tits

Marri

Richner

2014

“…The antioxidant property of carotenoids is, however, part of an ongoing debate (Costantini et al, 2007;Costantini and Moller, 2008;Hartley and Kennedy, 2004;Isaksson et al, 2007). There is a wide heterogeneity among studies that have explored the antioxidant nature of carotenoids.…”

Section: Immune Activation and Carotenoids Allocationmentioning

confidence: 99%

“…Nevertheless, it is important to keep in mind that the physiological properties of these pigments are currently under debate, since not all studies have provided support for the antioxidant function of carotenoids in vivo (Costantini and Moller, 2008;Hartley and Kennedy, 2004;Isaksson et al, 2007). For instance, Pike et al (Pike et al, 2007) have shown that carotenoid-supplemented male sticklebacks (Gasterosteus aculeatus) have a more exuberant nuptial coloration, a better survival rate, a higher reproductive output, and, more importantly, a reduced level of oxidative stress compared with control individuals, whereas Costantini et al (Costantini et al, 2007) did not report any effect of carotenoid supplementation on oxidative stress of nestling kestrels (Falco tinnunculus). It is not immediately clear why different studies have reported different results.…”

Section: Introductionmentioning

confidence: 99%

Age-dependent allocation of carotenoids to colorationversusantioxidant defences

Côté

Arnoux

Sorci

et al. 2010

SUMMARYAging is commonly attributed to age-related changes in oxidative damage due to an increased production of reactive oxygen species (ROS) and a weakened efficacy of enzymatic antioxidants. These age-related changes might therefore modify the use of dietary antioxidants, including carotenoids. As carotenoids are closely associated with the expression of secondary sexual signals, the allocation of carotenoids to sexual signal versus antioxidant defences may vary with age. In this study, we explored how carotenoid-based ornament and antioxidant activity varied with age and how an inflammatory-induced oxidative burst affected ornament and antioxidant activity across a range of ages. Using zebra finches (Taeniopygia guttata) as a model species, we assessed circulating carotenoids, beak coloration and the plasma antioxidant status of birds of different ages before and after an inflammatory challenge. Our results show that old individuals display similar carotenoid-based sexual signals regardless of the availability of circulating carotenoids, suggesting a terminal investment of old individuals in their last reproductive event. Additionally, we found that an inflammatory insult induced a decrease in the total antioxidant activity and in the expression of a carotenoid-based sexual signal in the oldest individuals. These results suggest that old individuals pay an extra cost of immune activation possibly because the efficiency of antioxidant machinery varies with age.

“…Pennycuick, 1968;Rothe et al, 1987;John et al, 1988;Bordel and Haase, 1993;Bordel and Haase, 2000;George and John, 1993;Schwilch et al, 1996). To quantify the oxidative status of this species, we determined, (1) the oxidative damage as serum reactive oxygen metabolites (ROMs; primarily hydroperoxides) and (2) the total (Costantini et al, 2006;Costantini et al, 2007a;Costantini et al, 2007b). Given that high activity levels may increase free radical production, we expected to find a positive association between flight time and oxidative stress.…”

Section: Introductionmentioning

confidence: 99%

Long flights and age affect oxidative status of homing pigeons(Columba livia)

Costantini

Dell’Ariccia

Lipp

2008

Self Cite

134

105

SUMMARYFlying is an energy demanding activity that imposes several physiological challenges on birds, such as increase in energy expenditure. Evidence from sports medicine shows that exhausting exercise may cause oxidative stress. Studies on avian flight have so far considered several blood parameters, such as uric acid, corticosteroids, or circulating free fatty acids, but only one study has analysed markers of oxidative stress in flying birds. In this study, we evaluated, for the first time, how different flight efforts affect the oxidative status using homing pigeons (Columba livia) as a model species. Two groups of pigeons flew for around 60 and 200·km, respectively. Pigeons that flew for 200·km had a 54% increase in oxidative damage as measured by serum reactive oxygen metabolites (ROMs), a 19% drop in total serum antioxidant capacity (OXY) and an 86% increase of oxidative stress (ROMs/OXYϫ1000). Older pigeons depleted more serum antioxidants regardless of the release distance. Among pigeons that flew the longer distance, heavier ones depleted less serum antioxidants. The results of the study suggest that long flights may cause oxidative stress, and that older individuals may experience higher physiological demands.