Studies On The Co-Culture Systems During Synchronization Of Nuclear And Cytoplasmic Maturation, Fertilization And Embryo Culture Of Porcine Oocytes In Vitro

The technology of maturation/fertilization in vitro (IVM/IVF) has become the basic technology of modern agriculture as well as biomedical study, however, the problems of the nuclear and cytoplasm maturation synchronization of oocyte, polyspermy and poor embryo development in vitro culture (IVC) of pig have not been solved efficiently compared with other domestic animals.In present study, synchronization of nuclear and cytoplasm maturation, fertilization and embryos culture were investigated during the co-culture systems in vitro to improve maturation quality of porcine oocytes, reduce polyspermy and increase the porcine embryos development. The different effects of cell monolayers on the maturation, fertilization and embryos development were researched according to the design when porcine ovarian cortex cells (pOCCs), porcine follicular granule cells (pFGCs), porcine oviductal epithelial cells (pOECs) and porcine cumulus cells (pCCs) were co-cultured individually with porcine oocytes, fertilized oocytes and embryos during IVM, IVF and IVC. It's the first time for pOCCs monolayer to be studied in the co-culture IVM system of porcine oocytes. The presence of the pOCCs monolayer during IVM significantly synchronized the nuclear and cytoplasm maturation of porcine oocytes compared with other co-culture groups and the control.The main objectives of the present study were to synchronize the nuclear and cytoplasm maturation of porcine oocytes during IVM, reduce polyspermy and improve empbryos development of the pig in vitro. In addition, the outcomes of the study could be regarded as one part of research and application basics in exploiting and utilizing heredity resource in pig or other mammalian. The results showed:1. The better dose of PMSG and hCG used in IVM of porcine oocytes is 10IU/ml. The presence of higher hormone concentration (15 IU/ml) did not result higher percentage of Pbâ… significantly (46.1 vs. 43.5, P>0.05) and the cumulus diffusion was restrained. The percentage of oocytes at Mâ…¡stage showed no significant difference when hormone exposure time was changed from 22 h to 44 h (64.6 vs. 61.8, P>0.05).2. The nuclear maturation of porcine oocytes was improved significantly during IVM when the oocytes co-cultured with the pOCCs monolayer, the pOECs monolayer or the pFGCs...