Effect of the hematopoietic growth factors erythropoietin and kit ligand on bovine oocyte in vitro maturation and developmental competence.

The overall aim of this work was to study the influence of the hematopoietic growth factors erythropoietin (EPO) and kit ligand (KITL) during bovine oocyte in vitro maturation (IVM). The effect of adding different concentrations of EPO or KITL to maturation medium was evaluated analyzing oocyte nuclear maturation, cumulus cells apoptosis, embryo cleavage, reactive oxygen species (ROS) production in matured oocytes and cleaved embryos and the developmental competence to the blastocyst stage. No significant differences were observed in the percentage of oocytes that completed nuclear maturation among treatments, but the percentages of cleaved embryos and blastocysts obtained increased. With the addition of both hematopoietic growth factors the percentage of cumulus cells undergoing apoptosis decreased, the number of blastomeres per cleaved embryo was larger and ROS production per cleaved embryo increased. In conclusion, although the addition of EPO and KITL hematopoietic growth factors during bovine oocyte IVM had no impact on nuclear maturation, it had a positive effect on oocyte cytoplasmic maturation and developmental competence.