Conservações e áreas afins - Comunicações orais

Coral reefs are one of the most diverse ecosystems on the planet, exercising a key role in maintaining ecosystem services that support thousands of human communities around the globe. However, this ecosystem has been suffering severe damage, occasioned mainly due to anthropogenic factors like the climate crisis. About 50% of the planet’s coral reefs have already been lost, and the rest are in a worrying situation. In this context, passive restoration alone seems no longer effective, and the development of reproductive biotechnologies aimed at conservation become crucial. Cryopreservation emerges as an alternative that can effectively help in the conservation of corals. The objective of this pioneering study was to develop an in vitro fertilization protocol using frozen sperm of the endemic species Mussismilia harttii. For the fertilization, spermatozoa were thawed and diluted to form inseminating doses at concentrations 105 and 107 spermatozoa/mL. In test tubes containing filtered sea water, fresh oocytes were added and then aliquots of the respective sperm concentrations. Two control treatments were used, one containing fresh semen and the other one containing only oocytes. After fertilization, the samples were transferred to 500 mL aquariums, with four replicates per treatment. The fertilization rate attained for all treatments was 100% and the larval settlement rate reached 26 ± 16%. We were able to create the first coral sperm bank in the South Atlantic, with an efficient in vitro fertilization protocol using frozen semen. This scientific achievement proves to be a powerful biotechnological tool that could help restore coral reefs and preserve their genetic diversity.