[目的]为探讨中草药发酵制剂缓解奶牛热应激的调控作用和缓解奶牛热应激的营养调控措施。[方法]选用胎次相近、健康无病,体况均匀的40 头,随机分成4 组,分别设置为对照组、试验Ⅰ组、试验Ⅱ组、试验Ⅲ组,每组5 个重复,每个重复2 头。对照组奶牛饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ组分别在饲喂基础日粮的基础上添加1%、2%和3%的中草药发酵制剂。[结果]通过检测生理指标、泌乳性能和血清生化指标结果表明,添加中草药发酵制剂后热应激奶牛的直肠温度和呼吸频次显著降低,平均日增重、平均日采食量显著提高,料重比显著降低（P<0.05）;奶牛的产奶量、乳脂率和乳蛋白率显著升高,体细胞数显著降低（P<0.05）;奶牛的白蛋白、总蛋白、尿素氮、血糖、谷丙转氨酶和谷草转氨酶含量均显著升高（P<0.05）。[结论]中草药发酵制剂可以有效缓解奶牛热应激,恢复正常的生理指标和血清生化指标水平,提高奶牛泌乳性能。在本试验条件下,日粮中中草药发酵制剂的适宜添加量为3%。

[Objective]To explore the regulatory effect of Chinese herbal fermentation preparations on alleviating heat stress in dairy cows and the nutritional regulation measures to alleviate heat stress in dairy cows. [Method]Forty healthy,disease-free,and even animals with similar parity were randomly divided into four groups: control group,test group I,test group II, and test group III. There were five replicates in each group,and two animals in each replicates. Cows in the control group were fed with the basic diet,and 1%,2% and 3% Chinese herbal fermentation preparations were added to the basic diet in groups Ⅰ,Ⅱ and Ⅲ respectively. [Result]The results of physiological indexes,lactation performance and serum biochemical indexes showed that rectal temperature and respiratory frequency of heat stressed dairy cows were significantly reduced,average daily gain and average daily feed intake were significantly increased,and feed weight ratio was significantly reduced （P<0.05）.The milk yield,milk fat rate and milk protein rate of dairy cows increased significantly,and the number of somatic cells decreased significantly （P<0.05）.The contents of albumin,total protein,urea nitrogen, blood glucose,glutamic pyruvic transaminase and glutamic oxaloacetic transaminase in dairy cows increased significantly（P<0.05）.Chinese herbal medicine fermentation preparation can effectively alleviate the heat stress of dairy cows,restore normal physiological and serum biochemical index levels,and improve the lactation performance of dairy cows. [Conclusion]The Chinese herbal medicine fermentation preparation can effectively alleviate the heat stress of dairy cows,restore the normal physiological and serum biochemical index levels,and improve the lactation performance of dairy cows. Under the experimental conditions,the appropriate addition amount of Chinese herbal medicine fermentation preparation in the diet is 3%.