减少奶牛热应激的营养和管理措施.pdf

Nutritional and Management Strategies to Reduce Heat Stress Impacts on Dairy Cows 减少奶牛热应激的营养及管理措施 Bob Collier Professor and Director University of Arizona 佐治亚大学教授、农学及生物学院院长 Introduction 介绍 • All animals have a zone of thermo neutral temperatures conducive to normal function 所有动物都有一个适合最佳功能的热中性温度区 • The upper critical temperature is where the effects of heat stress start to appear 达到这个临界温度的上限就就开始出现热应激 Heat Stress 热应激 • The point at which a dairy cow (or other animal) cannot dissipate an adequate quantity of heat to maintain body thermal balance or normal body temperature 热应激即奶牛不能释放足够的热量以维持身体热平衡或正 常的体温 Effect of Season on Milk and Protein Yield in Dairy Cows 季节对牛奶及乳蛋白产量的影响 39.00 1.15 38.00 1.10 37.00 ) d ) / d g 1.05 / k 36.00 g ( k d ( l n e i i