Could embryonic diapause facilitate conservation of endangered species?

Abstract

During embryonic diapause, the development of the embryo is paused shortly after conception by metabolic or seasonal factors. When conditions become favorable, the embryo will resume development after reactivation by the maternal reproductive system. Inducing this resting state in in vivo or in vitro manipulated embryos may offer invaluable advantages in the long-term storage of embryos, therefore offering a potential worthwhile and novel alternative in assisted reproduction compared to the currently broadly explored cryopreservation. In this reflection paper, a discussion is launched on how diapause-induced embryo preservation may support breeding programs of threatened and endangered wildlife species. Detailed research on the pathways behind initiation and maintenance of the dormant state of a blastocyst should be the first priority to facilitate the introduction of embryonic diapause as a novel tool in assisted reproduction. In addition, the examples of giant pandas are used to discuss how research on diapause mechanism can be launched within captive breeding programs to better facilitate genetic biodiversity management in species that express diapause.