本试验旨在研究饲粮添加超微粉碎车前对沙门氏菌感染肉仔鸡生长性能、免疫功能和抗氧化功能的影响。试验选用840只1日龄雄性科宝肉鸡，采用5（超微粉碎车前添加量）×2（是否沙门氏菌感染）双因子随机区组设计10个处理，每个处理6个重复，每个重复14只鸡。试验所用超微粉碎车前为车前草和车前子的超微粉碎混合物，混合比例为1 ：1。超微粉碎车前的添加量分别为饲粮的0、0.25%、0.50%、1.00%和2.00%，通过替代基础饲粮中小麦麸添加。感染组于7日龄每只鸡口服感染1 mL新鲜培养的鼠伤寒沙门氏菌（CVCC 541，细菌浓度为1×10⁹ CFU/mL），正常组于7日龄口服等量无菌营养肉汤。试验期为42 d。结果表明：1）饲粮添加超微粉碎车前对1~7日龄肉仔鸡生长性能无显著影响（P>0.05），沙门氏菌感染会显著降低肉仔鸡的生长性能（P<0.05），但是饲粮中添加超微粉碎车前对肉仔鸡生长性能无显著影响（P>0.05）。2）与未添加超微粉碎车前相比，饲粮添加0.50%的超微粉碎车前可以显著提高14日龄感染组及42日龄正常组肉仔鸡的脾脏指数（P<0.05），饲粮添加0.25%和1.00%超微粉碎车前显著降低感染组肉仔鸡回肠食糜分泌型免疫球蛋白A含量（P<0.05），饲粮添加2.00%超微粉碎车前可显著提高肉仔鸡21和42日龄外周血单核细胞吞噬活性（P<0.05），饲粮添加0.50%超微粉碎车前可显著提高感染组肉仔鸡21日龄外周血淋巴细胞刀豆蛋白A（ConA）刺激指数（P<0.05），饲粮添加1.00%和2.00%超微粉碎车前可显著提高肉仔鸡42日龄外周血淋巴细胞ConA刺激指数（P<0.05），饲粮添加0.50%和1.00%超微粉碎车前可显著提高肉仔鸡42日龄外周血淋巴细胞脂多糖刺激指数（P<0.05）。3）与未添加超微粉碎车前相比，饲粮添加0.50%超微粉碎车前可以显著降低肉仔鸡14日龄肝脏丙二醛含量（P<0.05），饲粮添加2.00%超微粉碎车前可以显著提高正常组肉仔鸡21日龄回肠总超氧化物歧化酶和谷胱甘肽过氧化物酶活性（P<0.05），饲粮添加0.50%超微粉碎车前显著降低感染组肉仔鸡肠道血红素氧合酶1基因表达量（P<0.05）。4）与未添加超微粉碎车前相比，饲粮添加1.00%超微粉碎车前可以显著提高肉仔鸡14、21日龄肠道绒毛高度和14日龄肠道黏膜层厚度（P<0.05）。综上所述，饲粮添加超微粉碎车前能够通过促进脾脏发育和淋巴细胞增殖分化来提高肉仔鸡机体的免疫能力，提高机体抗氧化能力，并对肉仔鸡肠道形态起到保护作用，在一定程度上缓解沙门氏菌感染对肉仔鸡的负面影响。

This experiment was conducted to study the effects of dietary superfine grinding plantain on growth performance, immune function and antioxidant function of broilers with Salmonella infection. A total of 840 1-day-old male Cobb broilers were selected and divided into 10 treatments by using a randomized block design of 5 (superfine grinding plantain supplementation levels)×2 (Salmonella infection or not) two factors with 6 replicates for each treatment and 14 chickens for each replicate. The superfine grinding plantain in this experiment was a mixture of superfine grinding plantain grass and plantain seed with 1:1 mixing ratio. The supplemental levels of superfine grinding plantain were 0, 0.25%, 0.50%, 1.00% and 2.00% of the diet, respectively, by replacing the wheat bran in the basal diet. Each broiler in the infected group was orally infected with 1 mL freshly cultured Salmonella Typhimurium (CVCC 541, bacterial concentration was 1×10⁹ CFU/mL) at the age of 7 days, and that in the normal group was orally infected with the same amount of sterile nutrient broth at the age of 7 days. The experiment lasted for 42 days. The results showed as follows:1) dietary superfine grinding plantain had no significant effects on the growth performance of broilers from 1 to 7 days of age (P>0.05), and Salmonella infection significantly reduced the growth performance of broilers (P<0.05), but dietary superfine grinding plantain had no significant effects on the growth performance of broilers (P>0.05). 2) Compared with no superfine grinding plantain supplementation, dietary 0.50% superfine grinding plantain significantly increased the spleen index of broilers at 14 days of age in the infected group and at 42 days of age in the normal group (P<0.05), dietary 0.25% and 1.00% superfine grinding plantain significantly decreased the chyme secretory immunoglobulin A content in ileum of broilers in the infected group (P<0.05), dietary 2.00% superfine grinding plantain significantly increased the peripheral blood monocyte phagocytic activity of broilers at 21 and 42 days of age (P<0.05), dietary 0.50% superfine grinding plantain significantly increased the concanavalin A (ConA) stimulation index in peripheral blood lymphocytes of broilers at 21 days of age in the infected group (P<0.05), dietary 1.00% and 2.00% superfine grinding plantain significantly increased the ConA stimulation index in peripheral blood lymphocytes of broilers at 42 days of age (P<0.05), dietary 0.50% and 1.00% superfine grinding plantain significantly increased the lipopolysaccharide stimulation index in peripheral blood lymphocytes of broilers at 42 days of age (P<0.05). 3) Compared with no superfine grinding plantain supplementation, dietary 0.50% superfine grinding plantain significantly decreased the malondialdehyde (MDA) content in liver of broilers at 14 days of age (P<0.05), dietary 2.00% superfine grinding plantain significantly increased the activity of total superoxide dismutase and glutathion peroxidase in ileum of broilers at 21 days of age in the normal group (P<0.05), and dietary 0.50% superfine grinding plantain significantly decreased the intestinal heme oxygenase 1 gene expression of broilers in the infected group (P<0.05). 4) Compared with no superfine grinding plantain supplementation, dietary 1.00% superfine grinding plantain significantly increased the intestinal villus height of broilers at 14 and 21 days of age and intestinal mucosa thickness of broilers at 14 days of age (P<0.05). In conclusion, dietary superfine grinding plantain can improve the immune ability of broilers by promoting the development of spleen and the proliferation and differentiation of lymphocytes, increase the antioxidant capacity, protect the intestine morphology of broilers, and alleviate the negative effect of Salmonella infection on broilers to some extent.