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bioRxiv · 10.1101/2020.06.22.165563

Life-long telomere attrition predicts health and lifespan in a large mammal

Abstract

Telomere length measured in blood cells is predictive of subsequent adult health and survival across a range of vertebrate species. However, we currently do not know whether such associations result from among-individual differences in telomere length determined genetically or by environmental factors early in life, or from differences in the rate of telomere attrition over the course of life. Here, we measured relative leukocyte telomere length (RLTL) multiple times across the entire lifespan of dairy cattle in a research population that is closely monitored for health and milk production and where individuals are only culled in response to health issues and less due to poor milk production than on purely commercial farms. Our results clearly show that the average amount of telomere attrition over an individuals life, not their average or early life telomere length predicted when an individual was culled. Within-individual telomere length attrition could reflect environmental or physiological insults which may accumulate to predict individual health-span. We also show that animals with more telomere attrition in their first year of life were culled at a younger age, indicating that early life stressors may have a prolonged effect on adult life.

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BibTeXRIS

Seeker, L. A., Underwood, S. L., Wilbourn, R. V., Fairlie, J., Froy, H., Holland, R., Ilska, J. J., Psifidi, A., Bagnall, A., Whitelaw, B., Coffey, M., Banos, G., Nussey, D. H.. 2020-06-23. Life-long telomere attrition predicts health and lifespan in a large mammal. https://doi.org/10.1101/2020.06.22.165563

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