Hormonal profile of Mediterranean green turtles (Chelonia mydas)

Abstract

: The beaches of Turkey are important nesting habitats of Chelonia mydas sea turtles and the determination of their health anddisease status is critical in sustaining healthy populations. Limited data currently exist on the hormone values required to determine thestatus of reproductive capabilities of sea turtles. This study aimed to collect basic data regarding their hormonal profile and set referencelimits for the Mediterranean population. Forty-nine free-ranging C. mydas sea turtles were used in the study and were classified into 3groups according to their age (hatchlings, juvenile, adult). Adult turtles were also grouped according to sex. Adult females were furtherdivided into 3 seasonal groups (summer, spring, and autumn), based on the dates of blood sampling. Plasma testosterone, oestradiol,progesterone, thyroxine (T4), triiodothyronine (T3), thyroid-stimulating hormone (TSH), cortisol, and corticosterone levels weredetermined by ELISA method. Significantly higher levels were observed in oestrogen (P < 0.001), progesterone (P < 0.001), cortisol (P