Cryopreservation of Musca domestica (Diptera : Muscidae) embryos

Prior studies on cryopreserving embryos of several non-drosophilid flies es tablished that two Drosophila,melanogaster, embryo cryopreservation protoco ls were not directly suitable for use with these species. This paper descri bes our work on developing a protocol for cryopreservation of embryos of th e housefly, Musca domestica. Significant progress was made when permeabiliz ation of the vitelline membrane was optimized, a vitrification solution con taining ethylene glycol, polyethylene glycol, and trehalose was formulated, and when cooling and recovery of the cryopreservation protocol included a step which passed the embryos through liquid nitrogen vapor. More than 70% of housefly embryos withstand treatments of dechorionation, permeabilizatio n, loading with cryoprotectant, and dehydration in vitrification solution, but the cooling, warming, and poststorage rearing steps still cause a consi derable reduction in survival. About 53% of the vitrified M. domestica embr yos hatched into larvae. Relative to the percentage of the control adult em ergence, about 13% of the embryos stored in liquid nitrogen developed into fertile adults. Hatching of the F-1 progeny of adults having been cryoprese rved as embryos was similar to control levels, (C) 2000 Academic Press.