冀北山区散栏奶牛舍夏季风机降温效果的研究

Study on Fans Cooling of Dairy Cowshed with Free Stall in Northern Mountainous Region of Hebei in Summer

试验旨在研究冀北山区夏季奶牛舍风机的降温效果。选择结构和饲养工艺相似的两栋舍饲散栏牛舍,分析安装风机对舍内温热环境、奶牛生理指标及产奶性能的影响。结果表明,安装风机舍的昼夜均温比对照舍低1.5℃,平均风速比对照舍高0.49m/s,可达0.66m/s。风机开启期间安装风机舍温湿指数(THI)显著低于对照舍(P<0.05)。此外,安装风机舍的奶牛直肠温度和呼吸频率显著低于对照舍(P<0.05),且每头牛每天产奶量比对照舍显著提高了17.0%(P<0.05),但乳脂率、乳蛋白和乳糖与对照舍相比差异均不显著(P>0.05)。由此可见,冀北山区奶牛舍安装风机可改善舍内温热环境,缓解奶牛热应激,提高奶牛的产奶性能。

The present objective of the study was to investigate the effect of fans cooling on dairy cow in northern mountainous region of Hebei in summer.Two cowsheds with the same structure and feeding technics were used to investigate the effect of fans on indoor temperature and humidity,physiological parameters and milking performance of dairy cow.The results showed that the average ambient temperature in cowshed with fans was 1.5℃lower than that of the control cowshed,and the average wind velocity was 0.49m/s higher than that of the control cowshed,reaching to 0.66 m/s.Temperature-humidity index（THI）of cowshed with fans was significantly lower than that of the control shed during the period of fans running（P〈0.05）.Besides,the rectal temperature and respiration rate of dairy cows in cowshed with fans were significantly lower than of the control cowshed（P〈0.05）,and the milk yield per cow per day was 17.0% higher than that of the control cowshed（P〉0.05）,however,the milk fat,milk protein and milk sugar were no significant difference from the control（P〈0.05）.Overall,fans could decrease indoor environment,moderate heat stress and increase performance and health of dairy cows in northern mountainous region of Hebei.