Effects Of Growth Factors And C-type Natriuretic Peptide On Goat Oocyte Maturation And Early Embryo Development

The efficiency of mammalian in vitro fertilization,parthenogenesis,and somatic cell cloning technology depends on the quality of oocytes used to produce embryos.Studies have shown that insulin-like growth factors(IGF1),leukemia inhibitory factor(LIF),and basic fibroblast growth factor(b FGF)can all promote the maturation of oocytes,and adding these three growth factors to the maturation fluid at the same time,after in vitro fertilization with the obtained oocytes,can greatly increase the rate of early embryo blastocysts and blastocyst quality.However,the effects of these three growth factors on the in vitro maturation of goat oocytes,and whether they are beneficial to improve the quality of in vitro maturation(IVM)oocytes and their ability to support embryonic development remain to be studied.Studies have also shown that C-type natriuretic peptides(CNP)is a paracrine factor naturally present in follicular fluid,which plays an important role in the inhibition of meiotic recovery of oocytes in goats,cattle and other mammals.This study mainly explores the effects of IGF1,LIF,and b FGF,the three growth factors and CNP on the vitro maturation of goat oocytes and the development of vitro fertilized embryos after maturation.It is expected to construct an efficient vitro maturation culture system for oocytes to improve the quality of goat oocytes cultured in vitro provides a theoretical basis for improving the efficiency of in vitro embryo production.The experimental results are as follows:1.The statistical results show that the optimal addition amounts of growth factors are b FGF 40 ng/m L,LIF 20 ng/m L,IGF 20 ng/m L;FLI group,CNP-OMM group and CNP-FLI group can all improve the culture of goat oocytes in vitro the maturity rate.2.The statistical results of vitro fertilization blastocyst development showed that different oocyte vitro maturation treatment groups could improve early embryo development,and the maturity rate of FLI group was significantly higher than that of CNP-OMM group and CNP-FLI group.3.The statistical results of the number of blastocyst cells and cell distribution showed that the number of blastocyst cells and the ratio of inner cell masses in the FLI group were significantly higher than those of the other two treatment groups.The quality of early embryos was considered to be higher than that of the CNP-OMM group and CNP-FLI group.4.Loss of maternal genes in oocytes will affect early embryonic development and even cause embryonic developmental block.The results of maternal gene detection in this study showed that the addition of growth factors can increase the expression of DNMT1,ZAR1 and NLRP5 in mature oocytes.5.Cumulus cell expansion-related genes are closely related to the maturation quality and developmental potential of oocytes.The test results of cumulus expansion genes in this study showed that growth factors can increase the expression of PTX3,TNFαIP6,PTGS2 and HAS2 in cumulus cells.In summary,this experiment established a high-efficiency vitro maturation culture system for goat oocytes,which can significantly improve the quality and early embryonic development potential of goat oocytes cultured vitro.Regarding the molecular regulation mechanism of the FLI culture system on the maturation of oocytes,we will further explore in the next research.