This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Breastfeeding is one of the most cost effective strategies known to public health for protecting infants against morbidity and mortality due to infectious diseases, notably acute diarrhea and acute respiratory infection. Enhanced immune response associated with human milk feeding has been attributed to a variety of immune factors in human milk including milk glycans. However, human milk varies in its composition between mothers, and over the course of lactation. While this variability is recognized, factors contributing to the variability have not been identified. Our long term goal is to identify maternal characteristics associated with milk glycans so that effective targeted intervention can occur. Ultimately, we expect this research will permit the improvement of infant health through dietary intervention. As a first step to identify maternal factors associated with variability in milk glycans we will examine, hormonal and dietary impact on milk glycans as well as how these milk glycans change through lactation. To accomplish this we will collect milk samples and perform mammary gland needle biopsies. We are planning to perform five collections per baboon during a 3 month period.