Meeting Abstract
Offspring growth rate and sex-specific development are key components of the natal life history stage. Nestling traits and stressors during this period can have long term fitness consequences. Telomeres, which are protective non-coding caps on the ends of eukaryotic chromosomes, shorten rapidly during development due to high rates of cell division and oxidative stress. Longer telomeres have been found associated with higher survival rates and better organismal performance. We examined the effects of nestling sex and growth rate on relative telomere length in North American barn swallow (Hirundo rustica erythrogaster) nestlings. Our study used a cross-foster design, where half of the eggs in experimental nests were switched with synchronously-laid eggs from other nests at the start of incubation. Nine days after hatching, nestlings were measured for body size and mass, and blood samples were taken for molecular sexing, quantification of relative telomere length, and for parentage analysis using microsatellite markers. At day twelve, morphological measurements were repeated to calculate growth rate. We used quantitative PCR to estimate relative telomere length in nestlings and found that male nestlings had relatively longer telomeres compared to female nestlings. Growth rate was not related to relative telomere length in either sex.
