黄芪多糖缓解肉牛短途运输应激的效果研究

为了研究黄芪多糖缓解肉牛短途运输应激的效果，选择15头（12月龄、体重250 kg左右）健康西门塔尔杂交肉牛，随机分至对照组、运输应激组和黄芪多糖处理组中，每组5头牛，黄芪多糖处理组牛给予10 g/（d·头）的黄芪多糖，运输应激组和黄芪多糖处理组进行3 h的60 km/h模拟公路运输。运输前1 d及运输后1、7 d采集所有试验牛的血样，测定相关生化指标，同时统计肉牛日增重和发病率。结果表明，运输应激组肉牛血清Na⁺在运输后1 d显著升高（P<0.05），对照组和黄芪多糖处理组在试验期间各时间点血清Na⁺、K⁺、Ca²⁺和Cl^-无显著差异（P>0.05）；运输应激组在运输后1、7 d的Na⁺/K⁺-ATP酶活性均极显著低于运输前1 d（P<0.01），血清SOD活性、GSH-Px活性均显著低于运输前1 d（P<0.05），运输后1、7 d血清MDA含量均显著高于运输前1 d（P<0.05），对照组和黄芪多糖处理组上述指标在试验期间均无显著变化（P>0.05）；对照组和黄芪多糖处理组运输后7 d平均日增重均极显著高于运输应激组（P<0.01），黄芪多糖处理组的呼吸道和消化道发病率均低于运输应激组。综上，黄芪多糖对肉牛短途运输应激防治具有一定的应用价值。

Effect of Astragalus Polysaccharides on Short-distance Transport Stress in Beef Cattle

To study the effect of Astragalus polysaccharide on short-distance transport stress in beef cattle,15 healthy and 12-month-old Simmental crossbred beef cattle were selected and randomly divided into control group,transport stress group and Astragalus polysaccharide test group with 5 cattles in each group.The cattles in Astragalus polysaccharide test group were fed with 10 g/d per head Astragalus polysaccharide during the experimental period.The cattles both in transport stress group and Astragalus polysaccharide test group were transported for 3 h at the speed of 60 km/h, and blood samples were collected and used for measuring some biochemical parameters. The daily gain and morbidity were measured simultaneously. The results showed that,in transport stress group,serum Na⁺ increased significantly in 1 d after transportation comparing to before transportation (P<0.05). serum Na⁺, K⁺, Ca²⁺ and Cl^- showed no significant difference during the experimental period in control group and Astragalus polysaccharide test group (P>0.05).After transport (1 and 7 d),blood Na⁺/K⁺-ATP activities were extremely significantly decreased (P<0.01), SOD and GSH-Px activities were significantly decreased (P<0.05), while serum MDA contentswere significantly increased (P<0.05) in transport stress group comparing with that at 1 d before transport.These indicators of the control and Astragalus polysaccharide test group showed no significantly difference during the experimental period (P>0.05); 7 d average daily gain after transportation of control group and Astragalus polysaccharide test group were extremely significantly higher than transport stress group (P<0.01), incidence rates of respiratory and gastrointestinal of Astragalus polysaccharide test group was lower than transport stress group. The results demonstrated that Astragalus polysaccharide could be applied to the transport stress for prevention and treatment in beef cattle.