Reconstruction of calf oocytes by germinal vesicle transfer in mature bovine oocytes : preliminary results

Oocytes collected from prepubertal calves lack developmental competence due to their failure or inability to complete ooplasmic maturation. In this study, in order to improve this competence, we transplanted nuclei isolated from GV stage calf oocytes in enucleated matured competent bovine oocytes and we demonstrated that our nuclear technique transplantation is highly effective in reconstituting calf oocyte at a rate of 76.34% and that the reconstructed oocyte can retain its ability to mature in vitro and to be normaly fertilized. The reduced rate of cleavage may be due to denuding required for the micromanipulation step, so, oocytes that receive a transferred GV must undergo the final stages of maturation and the early embryonic development without contacts with their cumulus cells.