Ovulation Induction with Follicle-Stimulating Hormone Administration in Hawksbill Turtles Eretmochelys imbricata

Abstract: To develop ovulation induction techniques, we investigated the effects of follicle- stimulating hormone (FSH) administration on ovulation in captive hawksbill turtles Eretmochelys imbricata. Porcine FSH preparation was administered by intramuscular injection to four hawksbill turtles with fully-developed follicles (21.6–23.8 mm, measured using ultrasonography) in July or August 2009. Blood samples were obtained and subjected to plasma progesterone measurement, and ovaries and oviducts were observed by ultrasonography just before, and 1–6 days after, FSH administration. One day after the administraion, the plasma progesterone concentration significantly increased from the basal level (<0.01–0.3 ng/mL) to 0.8– 5.1 ng/mL and then dropped to nearly the basal level within 2–4 days. The formation of eggshells was observed two days after FSH administration. These data collectively indicate that in hawksbill turtles FSH administration effectively induces ovulation, progesterone secretion, and egg formation.