In current study, one of the main challenges that all the biologists face is to overcome the problem of tissue heterogeneity for understanding the organ functions further. It is crucial to identify which cell populations produce specific molecules or to get relevant expression profiles reflecting in vivo.In order to study the characteristics of growth mammary gland cell in Yanbian dairy goat, we had established an dairy goat mammary epithelial cell (DGMEC) line of in vitro. Mammary tissues of Yanbian dairy goats were got by conventional operation method and dispersed and cultured in a medium containing fetal bovine serum.Epithelial cells were enriched by digesting with0.25%trypsin repeatedly to remove fibroblast cells and were identified as epithelial origin.The DGMECs displayed monolayer, cobble-stone, epithelial-like morphology, and formed alveolilike structures and island monolayer aggregates which were the typical characteristics of mammary epithelial cells.A onehalf logarithmically growth curve and cytoplasmic lipid droplets in these cells were observed. Embryonic stem cells have the ability to remain undifferentiated and proliferate in vitro while maintaining the potential to differentiate into derivatives of all three embryonic germ layers. The aim of the present study was to establish mouse ES lines from blastocyst stage embryos obtained after mice superovulation.We isolated, cultured and determined the characteristics of mouse embryonic stem cells in early passages. Therefore, we evaluated the morphological criteria for the approval of ES cells in early expansion stage. Embryonic stem (ES) cells with the capacity for germ line transmission have only been verified in mouse and rat.Methods for derivation, propagation, and differentiation of ES cells from domestic animals has not been fully established. Here, we describe derivation of ES cells from goat embryos. In vitro embryos were cultured on goat fetal fibroblast feeders. Embryos either attached to the feeder layer or remained floating and expanded in culture. Embryos that attached showed a prominent inner cell mass (ICM) and those that remained floating formed structures resembling ICM disks surrounded by trophectodermal cells. ICM cells and embryonic disks were isolated mechanically, cultured on feeder cells in the presence of LIF, and outgrown into ES-like colonies.Two cell lines were cultured for5passages. This cell line differentiated in vitro into epithelia and neuronal cells, and could be stably transfected and selected for expression of a fluorescent marker. Expression of known ES cell markers, maintenance in vitro in an undifferentiated state, differentiation in vitro provides evidence that the established cell line represents goat ES cells. Normal development of the mammary gland is a multidimensional process that is controlled in part by its mammary microenvironment. The microenvironment of mammary is a defined location that encompasses mammary somatic stem cells, neighboring signaling cells, the basement membrane and extracellular matrix, mammary fibroblasts as well as the intercellular signals produced and received by these cells.These dynamic signals take numerous forms including growth factors, steroids, cell-cell or cell-basement membrane physical interactions.Cellular growth and differentiation of the mammary gland throughout the developmental stages are regulated by changes in these signals and interactions. The purpose of this review is to summarize current information and research regarding the role of the mammary microenvironment during normal glandular development.