2007 Annual Report 1a.Objectives (from AD-416) The objective of the research associated with this Specific Cooperative Agreement is to evaluate alternative management practices that can be implemented to improve the health, productivity, and overall well-being of beef cattle. The research will include, but not be limited to, the evaluation of non-traditional nutritional supplements that may potentially enhance the immune system of beef cattle at critical periods of production. The key periods of production to be addressed will include prior to and immediately following production stressors such as transportation, vaccination, and weaning. 1b.Approach (from AD-416) Beef cattle will be supplemented with non-traditional nutritional supplements for a relatively short duration (approximately 3 weeks) either prior to or immediately following various management practices such as transportation, vaccination, and weaning which are known to cause stress in livestock and have negative impacts on health, productivity, and well-being. Animal health and productivity will be monitored prior to and following these management practices to determine if certain non-traditional nutritional supplements may provide immunological protection during these periods of stress. Prior to the large scale commercial-type studies, small scale studies will be conducted utilizing various immune challenge models in controlled environments to determine which nutritional supplements have immunomodulatory properties. 3.Progress Report This report documents research conducted under a Specific Cooperative Agreement between USDA-ARS, Cropping Systems Research Laboratory, Livestock Issues Research Unit, Lubbock, TX, and Texas Tech University. Additional details of research can be found in the report for the parent CRIS 6208-32000-004-00D, Development and Interpretation of Animal Well-Being Indicators to Assess Management Systems. The objective of the research associated with this Specific Cooperative Agreement is to evaluate alternative management practices that can be implemented to improve the health, productivity, and overall well-being of beef cattle. During this past year, ARS scientists conducted a collaborative research study with scientists from Texas Tech University to determine if the source and level of dietary energy consumed by feedlot cattle would influence their immune response to an endotoxin challenge. Results of this experiment indicate that decreasing the diet concentrate:roughage ratio increased production of pro-inflammatory cytokines in response to an endotoxin challenge in beef calves. A portion of this response seemed to be caused by decreased energy intake, whereas the remainder seemed to be a direct effect of the ingredients (e.g., grain vs. roughage) themselves. Additionally, administration of the antibiotic accelerated the febrile response to the endotoxin challenge. Consideration of potential immunomodulating effects of diets and how those effects may interact with cattle that have already been treated for disease may be warranted in future studies. Additional research is needed to confirm the results of this experiment and to determine the effects of the intensity of the pro-inflammatory cytokne response on cattle health in a commercial environment. The ADODR maintained regular contact with the cooperator via telephone calls, e-mails, and face-to-face meetings to review progress of the research and to verify appropriate use of funds.