Study On Production In Vitro Of Embryos And Cyopreservation Of Oocytes In Swine

It is the key step to establish a technique combination of maturation and fertilization in vitro of pig oocytes together with subsequently in vitro culture of embryos, and to further optimize their operational procedures and improve their efficiencies before making in vitro production (IVP) of porcine embryos come true. Currently, cryopreservation of pig oocyles had not yielded great breakthrough and the freezing protocol remained to be optimized. A systematic study on production in vitro of embryos and cryopreservation of oocytes in swine is conducing to consummation of the IVP technique combination, seeking for a new way to conserve genetic resource of swine efficiently. It is also conducing to the application of embryo bio-technology in pig, enriching the references in developmental biology. Therefore, it is quite significant in both academic and commercial areas. Slaughtered porcine ovaries were collected and used and the key factors that affected production in vitro of porcine embryos were investigated. The purpose of this study was to establish a simplified and efficient technique system, so as to establish a basis for building a platform of IVP of porcine embryos.1. Study on the key techniques for production in vitro of porcine embryosSlaughtered porcine ovaries were used to collect oocytes and the effects of different oocyte collection methods, ovary transportation temperatures, serum addition, hormones addition, porcine follicular fluid (pFF) addition, size of follicles and physiological status of ovaries and so forth on maturation and fertilization in vitro of oocytes were systematic comparatively studied in this experiment. The results showed that cutting method could result in significantly higher of total number or average number of oocytes per ovary than aspiration method did. However, the IVM rate (43.3%) of oocytes with cutting method was significantly lower than that from aspiration method (75.6%, P<0.05). Aspiration method could yield more available oocytes. When the temperature for ovary transportation was 37°C and 25°C, 76.7% and 80.2% of IVM rate, 52.2% and 52.4% of cleavage rate, and 17.7% and 18.1% of morula rate could be obtained. When the temperature droped to 15°C,...