Abstract
In order to deeply understand the effects of cryopreservation on the configuration of embryos,we chose the Eriocheir sinensis as the object,and observed the exterior shapes and interior structure of different developmental stages embryos after treatment with cryoprotectants and cryopreservation by means of microscope,slice and electron microscopy.Results showed that:(1) Cleavage embryos swelled clearly after treatment with vitrifying solutions by two-step methods,exterior shape of the embryos had no significant difference compared to the control group by three-step equilibration methods,some yolk overflowed from the inner cells and cells were damaged seriously after cryopreservation.(2) Exterior shape of gastrula stage embryos was similar to the control group after treatment with two-step equilibration methods,surface of gastrula stage embryo treated with cryoprotectants crinkled and shaped reticulation structure by scanning electron microscopy(SEM),white gobbet appeared in cells of embryos and fringe of cell was coarse and protuberant by transmission electron microscopy(TEM).After cryopreservation,color of embryos was pink,cell became opaque,the brim of cell membrane was blurry and shaped floss,segmental yolk was disintegrated into granule,the surface of embryos was sunken and wrinkled.(3) Cell membrane of embryos broke off,ice holes of different size appeared inside embryos,visible vacuoles appeared inside cells by slice observation.Ice holes in cells were very clear and some vacuoles appeared,about 80% mitochondria dissolved,breach of cells was very obvious by TEM.Exterior shape of the original zoea stage embryos had no difference compared to that of the control group after treatment with cryoprotectants by microscope and SEM.After cryopreservation,above 95% tissues shaped dispersion,partial yolk was disintegrated into granule,cell membrane of embryos broke off,ice holes appeared inside embryos.Surface of 90% embryos was sunken and wrinkled,but the cuticle of 10% embryos retained slick and intact by SEM.The results implied that the original zoea stage of embryos was the appropriate stage for cryopreservation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have