Objective: To evaluate the ability of bovine cumulus-granulosa cells to survive cryopreservation and subsequently support bovine embryo development during coculture.
Design: In vitro-matured and -fertilized bovine embryos (two- to four-cell) were allotted randomly to one of three treatment groups:  control medium alone consisting of Medium 199 containing 10% fetal bovine serum and antibiotics,  cocultured on fresh bovine cumulus-granulosa cells in control medium, or  cocultured on frozen-thawed cumulus-granulosa cells in control medium. Embryo development was assessed on days 7 and 8 after IVF.
Results: Coculture improved embryo development on days 7 and 8 compared with the control group. However, embryo development on days 7 and 8 did not differ among coculture groups.
Conclusions: Frozen-thawed cumulus-granulosa cells enhance embryo development similar to fresh cells during in vitro coculture.