Effects of increased begging and vitamin E supplements on oxidative stress and fledging probability

Offspring often use begging displays to demand food from parents. Begging is supposed to be a costly behavior, and oxidative stress is one potential cost of begging. We experimentally manipulated the begging intensity of great tit nestlings and the availability of vitamin E, an important antioxidant. The results suggest that oxidative stress is rather a minor cost of begging. However, nestlings supplemented with vitamin E were more likely to fledg

Data from: Do parasites and antioxidant availability affect begging behaviour, growth rate and resistance to oxidative stress?

Early-life trade-offs faced by developing offspring can have long-term consequences for their future fitness. Young offspring use begging displays to solicit resources from their parents and have been selected to grow fast to maximize survival. However, growth and begging behaviour are generally traded-off against self-maintenance. Oxidative stress, a physiological mediator of life-history trade-offs, may play a major role in this trade-off by constraining, or being costly to, growth and begging behaviour. Yet, despite implications for the evolution of life-history strategies and parent-offspring conflicts, the interplay between growth, begging behaviour and resistance to oxidative stress remains to be investigated. We experimentally challenged wild great tit (Parus major) offspring by infesting nests with a common ectoparasite, the hen flea (Ceratophyllus gallinae), and simultaneously tested for compensating effects of increased vitamin E availability, a common dietary antioxidant. We further quantified the experimental treatment effects on offspring growth, begging intensity and oxidative stress. Flea-infested nestlings of both sexes showed reduced body mass during the first half of the nestling phase but this effect vanished short before fledging. Begging intensity and oxidative stress of both sexes were unaffected by both experimental treatments. Feeding rates were not affected by the experimental treatments but parents of flea-infested nests fed nestlings with a higher proportion of caterpillars, the main source of antioxidants. Additionally, female nestlings begged significantly less than males in control nests, while both sexes begged at similar rates in vitamin E supplemented nests. Our study shows that a parasite exposure does not necessarily affect oxidative stress levels or begging intensity, but suggests that parents can compensate for negative effects of parasitism by modifying food composition. Furthermore, our results indicate that the begging capacity of the less competitive sex is constrained by antioxidant availability

Maronde_oxidative stress & fledging probability

Maronde_oxidative stress & fledging probabilit

Maronde_begging intensity and feeding rate

Maronde_begging intensity and feeding rat

Maronde_caterpillar_size

Maronde_caterpillar_siz

Maronde_body_mass_repeated

Maronde_body_mass_repeate

Data from Losdat et al. on the long-term effects of paraquat

The file entitled "Recruits" contains all the measurements made on the 39 recruits during the early-life of the offspring (in 2010) and the measurement of colour and oxidative stress taken on the same individuals as adults (in 2011). The file entitled "Sperm" contains the data on sperm performance measured on the individuals in 2011. Each line corresponds to the value for a single sperm cell

Data from: Effects of an early-life paraquat exposure on adult resistance to oxidative stress, plumage colour and sperm performance in a wild bird

1. Early-life stressful conditions can shape individual phenotypes and ultimately influence fitness. Oxidative stress is a pervasive threat that affects many fitness-related traits and can modulate life-history trade-offs. Yet, the extent to which exposure to oxidative stress during early life can have long-lasting effects on key fitness-related traits remains to be elucidated, particularly in natural populations of vertebrates. 2. Using a wild population of great tits Parus major, we experimentally dosed 11 day-old birds with paraquat, a pro-oxidant molecule, aiming at increasing oxidative stress. One year later, we recaptured 39 of them as adult recruiting breeders and quantified effects of the paraquat exposure on their resistance to oxidative stress, carotenoid-based plumage colouration and male sperm performance. 3. Despite the absence of a short-term effect of paraquat on oxidative stress measured two days later, the pre-fledging exposure to paraquat induced a reduction in individual oxidative damage measured at adulthood. Paraquat-dosed individuals also had brighter plumage, but no effect was observed on male sperm performance. 4. For the first time in a natural population of vertebrates, we experimentally show that an early-life acute exposure to a pro-oxidant has long-lasting effects on individual resistance to oxidative stress at adulthood. Our results are in line with the environmental matching and the hormesis hypotheses but may also reflect selective disappearance of individuals with lower resistance to oxidative stress