Telomere loss in relation to age and early environment in long-lived birds

Abstract

Shortening of telomeres, specific nucleotide repeats that cap eukaryotic chromosomes, is thought to play an important role in cellular and organismal senescence. We examined telomere dynamics in two longlived seabirds, the European shag and the wandering albatross. Telomere length in blood cells declines between the chick stage and adulthood in both species. However, among adults, telomere length is not related to age. This is consistent with reports of most telomere loss occurring early in life in other vertebrates. Thus, caution must be used in estimating annual rates of telomere loss, as these are probably not constant with age. We also measured changes within individuals in the wild, using repeat samples taken from individual shags as chicks and adults. We found high inter-individual variation in the magnitude of telomere loss, much of which was explained by circumstances during growth. Individuals laying down high tissue mass for their size showed greater telomere shortening. Independently of this, individuals born late in the season showed more telomere loss. Early conditions, possibly through their effects on oxidative stress, appear to play an important role in telomere attrition and thus potentially in the longevity of individuals.

Mother–offspring and nest-mate resemblance but no heritability in early-life telomere length in white-throated dippers

“…B 282: 20142924 found to be an important determinant of early-life RTL. Indeed, early development is a period characterized by rapid telomere shortening [59], and faster telomere shortening early in life has been demonstrated in the wild, e.g. in jackdaws (Corvus monedula) [8].…”

Capture and blood sampling do not affect foraging behaviour, breeding success and return rate of a large seabird: the black-browed albatross

“…Many studies have investigated the effects of the blood sampling process on terrestrial bird performances (Wingfield and Farner 1976;Dufty 1988;Hoysak and Weatherhead 1991;Lanctot 1994;Lubjuhn et al 1998;Perkins et al 2004;Schmoll et al 2004;Sheldon et al 2008), and this has led to the development of guidelines aimed at the ethical collection of blood that minimize the potential deleterious effects on birds Gaunt et al 1997;Sheldon et al 2008). However and surprisingly, accurate estimates of the impact of blood collection on performances of seabirds have rarely been conducted (Sheldon et al 2008, but see Brown 1995Van den Brink and Pigott 1996) despite an increasing number of eco-physiological studies focusing on these species (e.g., Kitaysky et al 1999;Criscuolo et al 2002;Hall et al 2004;Chastel et al 2005;Cherel et al 2005;Angelier et al 2007bAngelier et al , 2010. This is probably the case because seabirds have been considered less susceptible to handling than other birds.…”

Maternal telomere length inheritance in the king penguin

“…It remains then important to check inheritance of fitness-related traits, lifespan in our case and of the mechanisms susceptible to shape them. Telomere length is highly variable among age-matched individuals (a trait suggested to have an early-life origin; (Hall et al, 2004). Given significant heritability, telomere length variability is likely to provide a matrix for natural selection to act upon.…”