Variation in telomere length of the common carp, Cyprinus carpio (Cyprinidae), in relation to body length

Abstract

Determinations of the age structure of wild teleost populations are vital for sustainable management and conservation efforts. Yet the commonly applied increment-based ageing techniques are limited in some teleost species due to the subjectivity and interpretation of increment patterning, and destructive sampling. Here the application of telomere length as an alternate age determinate was assessed in wild caught specimens of the common carp (Cyprinus carpio). Telomere lengths were measured from muscle biopsies and fin clips using the absolute quantitative PCR method and correlated to specimen fork lengths. Measures of telomere lengths did not differ between sexes or states of sexual maturity. However, tissue type influenced telomere lengths, with telomere lengths measured in muscle biopsies significantly increasing with increased fork lengths of C. carpio. No discernable trend was seen for fin clip derived telomeres. High levels of variability in telomere length within and among size cohorts suggest that telomere length is not a suitable means of estimating the ages of C. carpio. The cross sectional design adopted here most likely masked complex telomeric dynamics at the individual level, which are influenced by intrinsic and extrinsic processes. Understanding the causative influences of these processes on the telomere lengths of C. carpio may aid in utilizing measures of telomere length as an alternate measure of an individual’s condition. Nevertheless, the need remains to develop novel non-lethal fish ageing techniques to overcome limitations of the current increment-based fish ageing technique.