Heat stress exerts significant negative impacts on the production performance, reproductive function, and immune system of dairy cows, leading to a 15%~20% decrease in milk yield, a 25%~35% reduction in conception rate, and various health disorders. This paper systematically elaborated the mechanisms through which heat stress affects dairy cows, with a focus on the scientific application strategies of reproductive hormones （such as GnRH and progesterone）, glucocorticoids （such as dexamethasone）, and melatonin in alleviating heat stress. Practical cases from dairy farms in both northern and southern regions demonstrate the effectiveness of hormonal regulation in enhancing stress resistance,improving reproductive efficiency, and restoring production performance. The study emphasized that hormone use should adhere to the principles of short-term and low-dose application, combined with comprehensive measures such as physical cooling and nutritional adjustments, to ensure dairy product safety and farming profitability. This paper provides a theoretical basis and practical guidance for dairy farms to mitigate heat stress.

heat stress  /  dairy cows  /  hormone application  /  management strategies