Preliminary Studies On The Issues Related To In Vitro Ferlitization Of Porcine Oocytes

The objectives of this study were to investigate: (1) Effects of sperm concentrations, sperm incubation time before insemination and sperm-oocyte co-incubation time on in vitro fertilization and further development of porcine oocytes in vitro; (2) Effects of different osmotic pressures and sorbitol concentrations in embryo culture medium on in vitro development of in vitro matured-fertilized porcine oocytes; (3) Effects of different sources of gonadotrophin on early parthenogenetic development of porcine oocytes in vitro, in order to increase the rate of porcine embryos production.Conclusions: (1) The sperm concentration of 1x10~6 /ml was relatively beneficial to porcine in vitro fertilization and subsequent early embryonic development. (2 ) Sperm incubation time before insemination had no significant effect on porcine in vitro fertilization and subsequent early embryonic development, and washed spermatozoa could be directly used for fertilization. (3) Sperm-oocyte co-incubation time also had no significant effect on porcine in vitro fertilization and subsequent early embryonic development in vitro, and 3h sperm-oocyte co-incubation time is relatively beneficial to porcine in vitro fertilization. (4) The osmotic pressure of NCSU-23 adjusted by NaCl up to 320～335mosm was relatively beneficial to the in vitro development of in vitro matured-fertilized porcine oocytes. (5) Addition of sorbitol into embryo culture medium (NCSU-23 ) was not beneficial to the in vitro development of in vitro matured-fertilized porcine oocytes. (6)There is no difference between the two sources of gonadotrophin selected in this study on early parthenogenetic development of porcine oocytes in vitro, and domestic makes of gonadotrophin has the same effect on early parthenogenetic development of porcine oocytes in vitro compared to imported makes.