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bioRxiv · 10.1101/669580

Influence of fats, carotenoids and POPs on the reproduction of the leatherback turtle

Marco, A.·Negro Balmaseda, J. J.·Navarro, J. C.·de Andres, E.
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Abstract

This study provides baseline data on fatty acid profiles and carotenoids in eggs of the leatherback sea turtle, Dermochelys coriacea. Correlations among such compounds, persistent organic pollutants, and reproductive parameters are also investigated. A number of 18 clutches were evaluated during June and August of 2008 at Reserva Pacuare Beach, in the Caribbean side of Costa Rica. Viability and fertility were calculated for each nest. Concentration levels of saturated and unsaturated fatty acids (SFAs and PUFAs), carotenoids and different congeners of persistent organic pollutants (POPs) were determined from egg-yolk samples. Mean {+/-} SD values were calculated for each compound and for each clutch. Correlations were performed searching for interactions among different compounds and for potential effects on reproductive parameters, thus all the studied compounds were related to each other and to any of the reproductive parameters. Low carotenoid levels characterized all eggs of this species, and a positive relationship between carotenoid concentrations and the viability rate was found. POPs and PUFA were positive and strongly correlated, suggesting molecular interactions. PUFAs appeared to increase fertility rate and hatchling length. This study provides potential evidences of PUFA enhancing fertility and hatchling size, and of carotenoids limiting vitellogenesis. The positive correlation found between POPs and PUFAs may indicate that harmful effects of these contaminants on the reproduction of leatherback turtles could be masked.

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Marco, A., Negro Balmaseda, J. J., Navarro, J. C., de Andres, E.. 2019-06-12. Influence of fats, carotenoids and POPs on the reproduction of the leatherback turtle. https://doi.org/10.1101/669580

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