Ketosis and heat stress are two of the most economically important pathologies that severely jeopardize the competitiveness of animal agriculture. Heat stress and ketosis affect herds of all sizes and every dairy region in the country. The biology of ketosis and heat stress has been studied for almost a half century, but the negative impacts of both are as severe today as they were 30 years ago. We suggest, based upon the literature and on our supporting evidence, that LPS is the common culprit etiological origin of both metabolic disorders. Taken together, our data and the literature suggests that LPS markedly alters nutrient partitioning and is a causative agent in the metabolic disruption during heat stress and ketosis. Identifying nutritional strategies to improve animal welfare and performance is critically important. The use of dietary chromium as a supplement may represent a practical avenue to maximize the animal response under these circumstances.
Dr. Lance Baumgard, Iowa State University
Dr. Baumgard grew up on a mixed livestock and row-crop farm in southwestern Minnesota. Lance received his B.S. and M.S. degrees from the University of Minnesota and his Ph.D. from Cornell University. He joined the University of Arizona's Animal Science and Human Nutrition departments in 2001 and then joined Iowa State University in 2009 as the Normal L. Jacobson Endowed Professor of Nutritional Physiology in the Department of Animal Science. Baumgard's primary research emphasis has been on the metabolic and endocrine consequences of heat stress in growing and lactating animals. Additionally, he has been studying how intestinal barrier hyper-permeability contributes to poor farm animal performance. Further, he is interested in determining the energetic requirements of immune activation and how nutrient partitioning is homeorhetically coordinated during an immune response. He is trying to identify nutritional strategies to improve intestinal barrier integrity in both monogastrics and ruminants.