The effects of cryoprotectants on sperm motility of the Chinese pearl oyster, Pinctada fucata martensii

Abstract

Cryopreservation has been widely employed to preserve genetic material of aquatic animals. Although of common use in bivalves, resulting effects due to the toxicity of the cryoprotectants dimethyl sulfoxide (DMSO), propanediol (PG), methanol (MET) and ethylene glycol (EG), upon sperm motility in the Chinese pearl oyster, Pinctada fucata martensii, has remained undocumented. This study endeavors to identify the least toxic among the effective cryoprotectant agents by observing and comparing their toxic effects on sperm motility under varying concentrations and duration of exposure. Sperm samples were exposed during controlled experiments, for 1, 3, 6, 9, 12 and 15 min durations, to each of the listed cryoprotectants at 5, 10, 15, and 20% (volume:volume) concentrations. Sperm motility was observed to diminish when exposed to all cryoprotectant solutions, and observations demonstrated that toxicity increased relative to both concentration and equilibration time. After 6 min of exposure to the cryoprotectants, sperm motility was seen to have diminished significantly in DMSO at just 5% concentration, and in MET, PG and EG at 10% concentrations, respectively (the values of the lowest observed effect concentrations). The relationship between the quantity of immotile sperm and the cryoprotectant concentration was described using the logarithmic regression equation. MET exhibited the lowest effective concentration required to inhibit sperm motility by 50% (EC), followed by EG, PG and DMSO, in order. Therefore, MET proved most toxic under the test conditions for sperm of P. fucata martensii, whereas DMSO, PG and EG were observed as comparatively safer, suggesting that DMSO, PG and EG warrant further study in the application of cryopreservation of Chinese P. fucata martensii sperm.

Primary Immunodeficiency

“…Besides, early and accurate molecular diagnosis is vital for guiding the selection of appropriate treatment including genetic therapy. Several molecular tests are available in identifying the genetic defects of PIDs, such as chromosomal analysis, fluorescence in situ hybridization, chromosomal microarray, single gene by Sanger sequencing, gene panels by massively parallel, whole exome, and genome by next-generation sequencing [52]. The selection of these assays should consider their inherent advantages and limitations [50,53].…”

Sperm cryopreservation of the noble Scallop Chlamys nobilis by a programmable freezing method: Effect of cryoprotectant

“…Studies on the mollusc sperm biological characteristics, cryopreservation and quality assessment have become more numerous since reviewed by Gwo (Gwo, ; Hassan, Qin, & Li, ). These studies concerned oyster species (Boulais et al, ; Suquet et al, ; Suquet, Rimond, et al, ), pearl oyster species (Demoy‐Schneider, Levêque, Schmitt, Le Pennec, & Cosson, ; Demoy‐Schneider, Schmitt, Le Pennec, Suquet, & Cosson, ; Zheng et al, ) and so on. However, studies for scallop species were limited to Pecten maximus (Suquet, Arsenault‐Pernet, Ratiskol, & Mingant, ; Suquet, Gourtay, et al, ; Suquet, Malo, et al, ; Suquet, Quéré, et al, ), Argopecten purpuratus (Lamarck, 1819) (Dupré, Covarrubias, Goldstein, Guerrero, & Rojas, ; Espinoza, Valdivia, & Dupre, ), Chlamys farreri (Li, Li & Xue, 2000; Xue, ) and Patinopecten yessoensis (Yang et al, ; Yang, Yang, Liu, & Zhou, , ).…”