大豆黄酮对热应激奶牛血细胞数和生理常数的影响

The Effects of Daidzein on the Routine Physical Parameters in Heat-stressed Dairy Cows

通过测定热应激状态下奶牛饲喂不同浓度大豆黄酮后血细胞数、体温、脉搏及呼吸数的变化,研究大豆黄酮对奶牛热应激的缓解作用。选取胎次、产奶量、泌乳期相近的40头中国荷斯坦牛,随机均分为4组(n=10)。试验Ⅰ、Ⅱ、Ⅲ组每头牛日粮中分别添加大豆黄酮200mg/d、300mg/d和400mg/d,对照组饲喂基础日粮,试验期60d。在试验开始时及试验第10、30、60天测定各组牛血液常规指标,且记录其体温(T)、脉搏数(P)和呼吸数(R)。结果表明,与对照组比较,试验组红细胞数、白细胞数、血红蛋白含量、体温均无显著变化(P>0.05),试验Ⅱ组、Ⅲ组脉搏数极显著降低(P<0.01);试验Ⅲ组呼吸频率显著降低(P<0.05)。试验证明,大豆黄酮可以通过调节机体代谢发挥抗热应激的作用,进而改善热应激奶牛的心肺功能。

Through determining the number of blood cells and the routine physical parameters in daidzein treated heat-stressed dairy cows to explore whether daidzein alleviate heat stress in dairy cattle or not. 40 Holstein cows with the similar parity, milk yield and lactation period were divided into 4 groups, randomly. Group Ⅰ,Ⅱ and Ill were added daidzein 200mg/d, 300mg/d, and 400mg/d last for 60 days, respectively. The control group was only fed the basal diet. At the 0, 10d, 30d, 60d, determination of the routine physical indicators including temperature （T）, pulse rate （P） and respiration rate （R） was performed. Compared with the control group, the red and white blood cells the content of haemoglobin and the temperature in experimental group had no significant changes （P〉 0.05）： The pulse number of group II and III cows decreased significantly （P〈0.01）; Respiration rate in group Ⅱ had a markedly decrease （P〈0.05）. Daidzein can play an important role in alleviating the heat stress in diary cows and thus improve the cardiopulmonary function of the heat-stressed cows.