Cryopreservation of sea urchin sperm and early life stages

Optimizing cryopreservation of sea cucumber (Apostichopus japonicus) sperm using a programmable freezer and computer-assisted sperm analysis

“…The development of cryopreservation protocols is important for protecting germplasm resources and solving the problem of germplasm degradation. Cryopreservation has many advantages, such as establishment of biobanks; providing year-round access to high quality material; breaking through geographic isolation; realizing remote hybridization; and protecting endangered species (Paredes, 2015;Paredes, 2016;Paredes et al, 2019). Compared with germplasm resources such as eggs and embryos, spermatozoa are easier to use in cryopreservation research due to their simpler structure (Tsai and Lin, 2012;Paredes et al, 2019;Campos et al, 2021).…”

“…Cryopreservation has many advantages, such as establishment of biobanks; providing year-round access to high quality material; breaking through geographic isolation; realizing remote hybridization; and protecting endangered species (Paredes, 2015;Paredes, 2016;Paredes et al, 2019). Compared with germplasm resources such as eggs and embryos, spermatozoa are easier to use in cryopreservation research due to their simpler structure (Tsai and Lin, 2012;Paredes et al, 2019;Campos et al, 2021). Generally, the sperm cryopreservation process includes sperm collection, quality evaluation, cryo-diluent (extender and cryoprotectant agent (CPA)) preparation, mixing of cryo-diluent with semen, cooling, storage, thawing, and sperm quality evaluation after thawing.…”

“…In contrast to the abundance of cryopreservation studies focused on mammals, fish, and plants, few studies of marine invertebrates have been reported (Paredes, 2015). Of the exiting studies, mollusks (mainly oysters) and echinoids (mainly sea urchins) together account for 72% of the research subjects (Liu et al, 2015;Paredes, 2015;Paredes, 2016;Paredes et al, 2019). At present, only two studies of cryopreservation of sea cucumber sperm have been published (Shao et al, 2006;Mizuno et al, 2019).…”

“…To date, most studies of cryopreservation of echinoderm sperm have controlled the freezing rate by adjusting the distance of the sample from the liquid nitrogen surface, and assessment of sperm motility has been conducted visually using an optical microscope. These methods have too many subjective factors and potential procedural errors to accurately assess the quality of frozen sperm (Dunn and Mclachlan, 1973;Asahina and Takahashi, 1978;Adams et al, 2004;Shao et al, 2006;Jalali and Crawford, 2012;Fabbrocini et al, 2014;Paredes, 2015;Paredes, 2016;Mizuno et al, 2019;Paredes et al, 2019).…”

Cold storage effects on lethal and sublethal responses of Amphibalanus amphitrite Nauplii

“…Cryopreservation of marine invertebrates has been proposed for several development stages and cell types (i.e., sperm, oocytes, embryos and larvae) from a wide number of different species (Guo and Weng 2020), with a high commercial and ecological value. Specific cryopreservation protocols have been developed for marine vertebrates and invertebrates (Paredes 2015;2019;Asturiano et al 2017), mainly on species of global economic importance, including fish, sea urchins, and mollusks used in aquaculture (Campos et al 2021;Cantarino Ribeiro et al 2018). As to crustaceans, few studies have been proposed for larvae cryopreservation, for example for penaeid prawn larvae (Arun and Subramoniam 1997;Subramoniam and Arun 1999) and barnacles larvae, including Balanus improvisus and A. amphitrite (Gakhova et al 1990;Khin-Maung-Oo et al 1998).…”