title: Preserving and using germplasm and dissociated embryonic cells for conserving Caribbean and Pacific coral.
abstract: Coral reefs are experiencing unprecedented degradation due to human activities, and protecting specific reef habitats may not stop this decline, because the most serious threats are global (i.e., climate change), not local. However, ex situ preservation practices can provide safeguards for coral reef conservation. Specifically, modern advances in cryobiology and genome banking could secure existing species and genetic diversity until genotypes can be introduced into rehabilitated habitats. We assessed the feasibility of recovering viable sperm and embryonic cells post-thaw from two coral species, Acropora palmata and Fungia scutaria that have diffferent evolutionary histories, ecological niches and reproductive strategies. In vitro fertilization (IVF) of conspecific eggs using fresh (control) spermatozoa revealed high levels of fertilization (>90% in A. palmata; >84% in F. scutaria; P>0.05) that were unaffected by tested sperm concentrations. A solution of 10% dimethyl sulfoxide (DMSO) at cooling rates of 20 to 30°C/min most successfully cryopreserved both A. palmata and F. scutaria spermatozoa and allowed producing developing larvae in vitro. IVF success under these conditions was 65% in A. palmata and 53% in F. scutaria on particular nights; however, on subsequent nights, the same process resulted in little or no IVF success. Thus, the window for optimal freezing of high quality spermatozoa was short (∼5 h for one night each spawning cycle). Additionally, cryopreserved F. scutaria embryonic cells had∼50% post-thaw viability as measured by intact membranes. Thus, despite some differences between species, coral spermatozoa and embryonic cells are viable after low temperature (-196°C) storage, preservation and thawing. Based on these results, we have begun systematically banking coral spermatozoa and embryonic cells on a large-scale as a support approach for preserving existing bio- and genetic diversity found in reef systems.
authors.affiliation: Department of Reproductive Sciences, Smithsonian Conservation Biology Institute, Front Royal, Virginia, United States of America. hagedornm@si.edu
authors.forename: Mary
authors.initials: M
authors.lastname: Hagedorn
authors.forename: Virginia
authors.initials: V
authors.lastname: Carter
authors.forename: Kelly
authors.initials: K
authors.lastname: Martorana
authors.forename: Malia K
authors.initials: MK
authors.lastname: Paresa
authors.forename: Jason
authors.initials: J
authors.lastname: Acker
authors.forename: Iliana B
authors.initials: IB
authors.lastname: Baums
authors.forename: Eric
authors.initials: E
authors.lastname: Borneman
authors.forename: Michael
authors.initials: M
authors.lastname: Brittsan
authors.forename: Michael
authors.initials: M
authors.lastname: Byers
authors.forename: Michael
authors.initials: M
authors.lastname: Henley
authors.forename: Michael
authors.initials: M
authors.lastname: Laterveer
authors.forename: Jo-Ann
authors.initials: JA
authors.lastname: Leong
authors.forename: Megan
authors.initials: M
authors.lastname: McCarthy
authors.forename: Stuart
authors.initials: S
authors.lastname: Meyers
authors.forename: Brian D
authors.initials: BD
authors.lastname: Nelson
authors.forename: Dirk
authors.initials: D
authors.lastname: Petersen
authors.forename: Terrence
authors.initials: T
authors.lastname: Tiersch
authors.forename: Rafael Cuevas
authors.initials: RC
authors.lastname: Uribe
authors.forename: Erik
authors.initials: E
authors.lastname: Woods
authors.forename: David
authors.initials: D
authors.lastname: Wildt
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000166:cytology*; D017691:Caribbean Region; D002470:Cell Survival; D015925:Cryopreservation / Q000379:methods*; D005307:Fertilization in Vitro; D005854:Germ Cells; D008297:Male; D010140:Pacific Ocean; D013076:Sperm Count; D013081:Sperm Motility; D013094:Spermatozoa / Q000166:cytology*