Abstract #359

# 359
Practical considerations for feeding cows under heat stress.
Duarte Diaz*1, 1University of Arizona, Tucson, AZ.

Heat stress is a major cause of production losses in the dairy industry with some estimates indicating that it could be costing dairy producers globally into the billions of dollars. In commercial operations, prevention of physiological responses to heat stress is far more effective than mitigation post exposure. Because these responses are a result of a confluence of factors, the approach to mitigation is often complex in nature. Dietary adjustments can play an important role in heat stress management. Their primary role is to first prevent, delay or minimize intake reduction and second to compensate for higher nutrient needs during these periods of high demands (e.g., mineral losses, oxidative stress). Lastly, maintaining intestinal health during high THI periods can also play an important role in prevention or delaying of heat stress related production losses. Therefore, nutritional adjustments can be utilized strategically during these periods to reduce the impact of heat stress. Supplementation with feed additives that target affected system could offer beneficial returns on investments for dairymen and nutritionist. The following review will attempt to discuss the field tools utilized by dairy producers and their nutritionist to cope with the complex responses associated with heat stress. We will discuss the link between management tools and nutrition and explore feed additives and their potential roles in heat stress management at the farm. Lastly, we will discuss the limitation of some heat stress experimental models and discuss why some field research observations could be beneficial in the interpretation of effectiveness intervention strategies.



Speaker Bio
Duarte E. DĂ­az holds MS and PhD degrees in nutrition from North Carolina State University. He has given over 40 invited presentations around the world and has published over 70 articles in scientific journals, proceedings, and popular press magazines. In 2005, Diaz served as editor of a publication that focused on the applied impact of mycotoxins on agriculture (The Mycotoxin Blue Book; Notthingham University Press). The book has sold over 5,000 copies and is widely considered an important reference on the subject. Diaz has worked in Academia at several institutions including Utah State University, University of Bologna, and the Catholic University of the Sacred Heart in Italy. In 2015, after several years working in the private sectors, Diaz joined the faculty at the University of Arizona as an associate professor and dairy extension specialist.