Michael Van Amburgh

My program is devoted to discovery and problem solving contemporary issues in nutrition, physiology and management in the dairy and livestock industries and disseminating new knowledge to students and the industry.

Research Focus

Research efforts in my laboratory are multifaceted and focused on several aspects of productive efficiency of dairy cattle. With increasing pressure on the dairy industry to reduce the environmental impact of cattle, we are currently working on developing a basic understanding of whole animal nitrogen metabolism and efficiency of use of absorbed amino acids. We have embarked on several studies employing stable isotopes of nitrogen compounds to understand urea nitrogen recycling and the ultimate distribution and partitioning of intake nitrogen on a systems basis. This work is leading to new dietary strategies that allow nutritionists to reduce the amount of nitrogen (crude protein) fed to lactating cows while maintaining milk production thus improving the efficiency of use of absorbed feed nitrogen and reducing the amount of manure nitrogen excreted into the environment per unit of milk produced. Data from studies like these are being used further develop the Cornell Net Carbohydrate and Protein System (CNCPS). Recent application of this new knowledge and improvements in the model have allowed us to formulate diets for high producing lactating cattle at 14% CP while maintaining milk yield in excess of 43 kg/d.

My group is furthering this work with new studies examining the role of carbohydrate digestion and site of digestion on the partitioning of those substrates to milk. This has direct effects on the overall efficiency of the animal and how absorbed amino acids are utilized. We are embarking on studies that allow us to further describe the efficiency of use of absorbed amino acids with the goal of further enhancing the efficiency of use of protein by the lactating dairy cow. In support of this work, we have developed an assay that allows us to predict the indigestibility of nitrogen containing feeds in the small intestine of the cow. This is aiding our ability to determine what is first limiting in dairy cattle diets.

In support of the CNCPS, we are also developing new tools to describe how NDF digestion occurs in various feeds. Our focus is primarily forages and our goal is to better describe the rate and extent of NDF digestion for use in the model with the objective of linking this to dry matter intake and whole farm forage allocation to reduce the importation of non-farm raised feeds, thus reducing the importation of nutrients such as phosphorous and nitrogen.

Finally, the lab has a 20 year history of engaging in research to enhance our understanding of the nutrient requirements and management of calves and heifers. Previous work identified time and not nutrient intake as the primary factor influencing pre-pubertal mammary development as measured by DNA. This has significant implications for years of research into this very perplexing and controversial issue and allows us to redirect of efforts on factors that can be manipulated and have a larger impact on future milk potential. To that point, recent work has demonstrated that early life nutrient intake and growth rates prior to weaning have an epigenetic or developmental effect on the calf that results in greater milk yield over the life of the animal as an adult. Further, in collaboration a some colleagues, we were able to demonstrate that pre-weaning growth rates accounted for up to 25% of the variation in first lactation milk production. This is a significant finding and one that provides us with a new direction and with profound implications for early life management of calves and heifers. Further, as part of the research into early life, we have started to understand the role that components of colostrum play in communicating to the neonate and are currently conducting work to appreciate the effect of those lactocrine signals.

Outreach and Extension Focus

I do not have an official extension appointment, but because of the focus of my research and teaching program, I am asked to participate in extension and educational programs around the state and around the world. My extension activities are related to the Pro-Dairy program and other extension programs in the state. I do not have a formal extension program but am involved in developing activities like Winter Dairy Management meetings when the topic requires my expertise. I do extension meetings around the state if time allows and the topic is pertinent to my research and teaching. This impacts mostly producers and feed industry professionals in the state.

My outreach activities are a function of my research program. Due to my involvement with the Cornell Net Carbohydrate and Protein System and CPM Dairy, I spend a significant amount of time training and communicating with the dairy and livestock industry – including producers, feed chemists, nutritionists and academics, about how to apply and interpret the model. This takes place on a state, national and international basis. For example, I spoke at the National Forage Testing Association meeting about chemical analyses required for better prediction of cattle requirements and the variation associated with many of these assays. This impacts anyone that sends a sample into one of those labs, since we guide the procedures.

In addition, my research work in several areas of ruminant growth, development, nutrition and physiology has some basis in application and results in my being asked to various conferences in the U.S. and elsewhere.

Teaching Focus

My teaching focus is undergraduate and graduate student programs in animal science, dairy management, nutrition, and physiology. I believe in integrating our understanding of the biological principles of dairy cattle function and metabolism with management and quantitative decision making to improve productivity of whatever management system students encounter. It is also important to link concepts with practice and this is done through experiential learning activities I develop as part of the Dairy Fellows Program and overall dairy program. I also advise the Cornell University Dairy Science Club and through that have developed several international experiential learning courses to expose students to other cultures, production and food systems.