中文摘要：

选择同处于泌乳后期、日均产奶量相当的荷斯坦奶牛3头。每天早上挤奶后．于右后乳区经过乳头管灌注黄芪多糖（APS）20mL，左后乳区注入20mL生理盐水（PSS）作为对照，连续10d。第11天早上挤奶后，两侧乳区均灌注含有100μg大肠杆菌内毒素的生理盐水10mL。分别于灌注黄芪多糖前、灌注内毒素前1h及灌注后3、6、9、12、2dh采集两个乳区的乳样进行指标测定。实验结果表明。与灌注内毒素前相比，灌注PSS的对照乳区乳中的N-乙酰-β-D-氨基葡萄糖苷酶（NAGase）活力在注入内毒素后9h时达到峰值（12．65U／mgprotein），24h时乳中NAGase活力下降到灌注内毒素前的水平（P〉0．051；而施用了APS的实验乳区，在注入内毒素后，乳中的NAGase活力6h时达到峰值（16．79U／mgprotein），9h时乳中NAGase活力已下降到灌注内毒素以前的水平（P〉0．05）。总抗氧化能力（T—AOC）的测定结果表明。奶牛乳导管注入内毒素后。两种处理的乳区乳中的总抗氧化能力显著下降（P〈0．05），两种处理的乳区乳之间比较无显著差异（P〉0．05）。结果表明．通过乳头管连续灌注APS，可使乳中多形核嗜中性白细胞fPMN）快速聚集到感染部位消灭抗原．有助于奶牛乳腺炎的预后良好。

英文摘要：

Three Holstein dairy cows in their late lactation were used in this study. They were milking the same milk production. The mammary right hind quarters of 3 dairy cows were infused with 20mL of Astragalus Polysaccharide（APS）. Left hind quarters were used as controls and infused with 20mL of sterile physiological saline solution（PSS）. The administration of APS had been continuing for ten consecutive days. On the eleventh day, after morning milking, the mammary quarters （both right hind and left hind） of 3 cows were infused with 10mL saline containing 100μg LPS. At varying intervals before and after infusion （-1, 3, 6,9,12 and 24h）, inflammation and rectal temperature were recorded, and quarter milk samples were collected. The NAGase activity in the milk from quarters administered with PSS had reached the peak at the 9^th hour and declined to the normal level at 24^th. While the NAGase activity in the milk from quarters administered with APS had reached the peak at 6^th and declined to the normal level at 9^th. Compared to the pre-infusion of LPS, T-AOC in the milk from quarters administered both PSS and APS had decreased significantly.These findings suggest that administration of APS can induce the prompt recruitment of PMN to the site of infection and annihilate antigen, and make for inflammatory mammary gland recovery.