Meeting Abstract

P1-128   -   A method for the collection of early-stage sea turtle embryos Gárriz, A; Williamson, SA*; Evans, RG; Reina, RD; Monash University, Melbourne, Australia; Florida Atlantic University, Boca Raton and Monash University, Melbourne, Australia; Monash University, Melbourne, Australia; Monash University, Melbourne, Australia sean.alexander.williamson@gmail.com https://www.researchgate.net/profile/Sean-Williamson-2

Early-stage turtle embryos, immediately after oviposition, are very small (<5 mm diameter), hindering research on embryonic development at such early stages. When turtle eggs fail to hatch and no embryo is seen with the naked eye it is unclear whether the eggs have been fertilized and contained a viable embryo at oviposition or were not fertilized. Embryos that die at an early stage of development are difficult to detect, especially under field conditions, due to their microscopic size. Further, little is known about the molecular pathways that promote and regulate early developmental processes in turtles and some processes apparently are unique to this taxon, such as pre-ovipositional embryonic arrest. To enable further analysis of these and other processes critical to early embryonic development in chelonians, a reliable method for extraction of early-stage embryos from the egg was developed. We describe a technique for extracting green turtle (Chelonia mydas) embryos at very early stages and measuring RNA as discriminator of development. Total RNA of 10 turtle embryos was extracted to validate the method. Total RNA concentration was above 5 ng µl-1 and the RNA Integrity Number (RIN) varied between 7.0 - 10.0; which is considered acceptable quality for further RNA-sequencing analyses. This technique could be employed when investigating fertilization rates of turtle nests and for further investigation of the molecular biology of embryonic development in turtles. Furthermore, the technique should be adaptable to other oviparous species with similar eggs.