RESUMEN
High throughput methods to assess genomics, gene (mRNA) expression, and protein composition of tissues and body fluids has led to a rapid advancement in understanding of normal and abnormal function of many body systems across a wide variety of mammalian and non-mammalian animal species. Over the past several years, our laboratory has applied these techniques to the study of normal physiology and disease of the pregnant mare, in particular for the placenta and fetal fluids. Although our understanding of the endocrine aspects of pregnancy in mares is reasonably advanced, much of our understanding related to placental function and dysfunction remains limited. This review will cover a number of studies which detail normal gestational changes in the fetal and maternal placenta along with changes in gene expression in a number of late gestational diseases of pregnancy.