Based on the principle of milk yield,lactation day and close body weight,20 Holestein dairy cows were selected and randomly divided into control group and test group, 10 in each group;the test group was treated with spraying + fan cooling method. The results showed that the spraying + fan method could increase dairy milk yield and 4% standardized milk by 2. 66 kg/d(P＜0. 05)and 2. 81 kg/d(P＜0. 01)re-spectively,the average of rectum temperature, respiratory rate and heart rate decreased 2. 02℃ , 36. 8 times/min and 3. 8 times/min(P＜0. 01)respectively,and with the climb of the temperature,the physiological indexes declined remarbly;in addition,the physioloical indexes declined remarbly;in addition,the spraying-)-fan method had decreased the hemoglobin,red blood cell count and PCV in blood indexes of dairy cows in heat-stress period byll. 75 g/L,0. 72×1012/L and 2. 63%(P＜0. 01)respectively. The results indicated that the spraying+fan cooling system can significantly improve the effect of heat stress in dairy cow, thus improving the productive performance.%试验按产奶量、泌乳时间、体重相近的原则选择20头荷斯坦奶牛,随机分成对照组和试验组,每组10头；试验组采用喷淋+风扇方式降温处理,对照组采用风扇通风的方式.结果表明,喷淋+风扇的降温措施可使每牛日产奶量和4％标准乳分别提高2.66 kg/d(P＜0.05)和2.81 kg/d(P＜0.01)；直肠温度、呼吸频率和心率的平均值分别降低2.02℃、36.8次/min和3.8次/min(P＜0.01),且随着环境温度的升高,各生理指标下降的幅度越大；此外,喷淋+风扇的降温措施使热应激期奶牛血液指标中血红蛋白、红细胞数和红细胞压积值分别降低了11.75 g/L、0.72×1012/L和2.63％(P＜0.01).试验结果表明,喷淋+风扇降温系统能明显改善热应激对奶牛的影响,提高生产性能.
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