Gonadotropin-Releasing Hormone efficacy on different developmental stages of embryo in bovine

In vitro embryo production (IVEP) has been used for both research and production purposes in cattle. Through analysis of IVEP، detailed mechanisms involved in natural embryo production can be revealed and further the embryo transfer techniques and transgenesis can be facilitated. Although Gonadotropin-Releasing Hormone effects in regulating and controlling the animal reproduction in clinical studies have been well-documented، studies considering the effects of topical process، folliculogenesis، oocyte maturation، fertilization and embryo development are almost lacking. In this study، The effects of different concentrations of Gonadotropin-Releasing Hormone on the process of fertilization and embryo development was evaluated. Collected oocytes (1091 cells) placed in in vitro fertilization media and in vitro culture media، supplemented by 0. 8، 1 and 1. 5 µg/ml of GnRH. Based on microscopic analysis، The cleavage rate and blastocyst rate increased in the in vitro fertilization media and in vitro culture media containing of Gonadotropin-Releasing Hormone but this increased was not statistically. Moreover، by incorporating of GnRH to in vitro culture media، the number of trophectoderm and total cells were increased (p<0. 05).