My professional activities are centered around an understanding of the role of hormones in regulating mammalian metabolism. My research activities involve many animal models (mouse, sheep and cattle), based on the fact that each offers unique opportunities and unique metabolic challenges. My research has implications for both animal agriculture and human health.
The overall goal of my research program is to understand the regulation of metabolism, growth and development by hormones. We pursue this goal at molecular, cellular and organismal levels in the context of problems relevant to animal agriculture and medicine. At the present time, my research efforts are focused on 3 specific areas. 1) Hormonal coordination of metabolism in energy deficient ruminants: Dairy cattle experience dramatic changes in metabolism during the period from pregnancy to lactation when they enter a period of severe nutritional insufficiency. The goal of this research program is to identify the roles of growth hormone (GH) and leptin in inducing beneficial adaptations in the early lactating dairy cows. 2) Effect of fetal under-nutrition on postnatal energy metabolism: Epidemiological studies of human populations link fetal under-nutrition to juvenile obesity and chronic diseases during adult life. The goal of this research is to identify causal relation between intrauterine under-nutrition, impaired fetal hypothalamic development and postnatal obesity using a sheep model. 3) Regulation and function of vascular insulin-like growth factors (IGF-I): IGF-I is necessary for normal body growth and for the development of specific tissues (muscle, bone, mammary gland, etc) and is involved in diseases such as cancer and diabetes and in the aging process. The goal of this research is to identify the role played by liver derived IGF-I in various genetically engineered mice models subjected to anabolic or catabolic conditions.
I teach Biology of the Mammary Gland in Health and Disease ( ANSC/BIOAP 3410). This is a capstone course in physiology directed to students interested in both basic and translational aspects of lactation. I also co-teach the in Mechanisms of Growth and Development (ANSC3920). This is a course directed to students primarily interested in recent advances in growth biology with a focus on major metabolic tissues and their regulation by hormones.