脱氧雪腐镰刀菌烯醇对断奶仔猪生长性能、血清细胞因子及肠道免疫水平的影响

[目的]本试验旨在通过脱氧雪腐镰刀菌烯醇（DON）体内试验，根据仔猪血清细胞因子水平、肠黏膜sIgA水平及肠道免疫球蛋白mRNA相对表达量的变化，研究DON对断奶仔猪免疫机制的影响。[方法]选取30头21日龄"杜×长×大"三元杂交断奶仔猪，随机分为对照组、DON低剂量组和DON高剂量组，对照组饲喂基础饲粮，低剂量组和高剂量组分别饲喂含1和2 mg？kg-1 DON的基础饲粮。试验期60 d。在试验开始后的0、14、28、42和60 d，所有仔猪经前腔静脉采血，检测血清细胞因子IFN-γ、IL-2、IL-4和IL-6水平；试验结束时，每组随机选取5头仔猪剖杀，取十二指肠、空肠和回肠，检测肠道黏膜sIgA水平及肠组织IgA、IgM、IgG mRNA相对表达量。[结果]DON能显著或极显著降低仔猪平均日采食量与平均日增重，增加料重比（P<0.05，P<0.01）；显著降低血清IFN-γ、IL-2、IL-4、IL-6水平和小肠黏膜sIgA水平及小肠组织IgA、IgM、IgG mRNA相对表达量（P<0.05），其中DON高剂量组的作用效果比低剂量组更加明显。[结论]DON可以降低仔猪的生长性能、血清细胞因子及肠道免疫水平，对断奶仔猪具有一定的免疫毒性作用。
[Objectives] An experiment was conducted to investigate the immunotoxicity of piglets in vivo exposed by deoxynivalenol (DON), conferring to the levels of serum cytokines, sIgA and mRNA relative expression of intestinal immunoglobulin in weanling piglets. [Methods] Thirty crossbred piglets "Duroc×Landrace×Yorkshire" (21 days old)were selected and randomly divided into three groups of ten piglets each. Piglets in control group were fed with the basal diet, low and high dosage of DON groups were fed with 1 and 2 mg？kg-1DON diet. The trial was conducted for 60 days. Blood samples were collected from each piglet anterior vena cava for measuring serum IFN-γ, IL-2, I L-4, IL-6 levels on 0, 14, 21, 28, 42 and 60 d. At the end of experiment, five piglets from each group were sacrificed, and the intestinal mucosa was collected to detect the levels of sIgA. Each segment of the intestine was collected to determine the relative expression of IgA, IgM, IgG mRNA. [Results] Compared with the control group, DON decreased average daily gain (ADG)and average daily feed intake (ADFI)of piglets significantly (P<0.05 or P<0.01)and increased the ratio of feed to gain significantly (P<0.05 or P<0.01);DON reduced the above four kinds of serum cytokines, and decreased the sIgA levels in intestinal mucosa and IgA, IgM and IgG mRNA relative expression in small intestinal tissues significantly (P<0.05). The negative effect of high dosage of DON group was potent. [Conclusions] DON could reduce growth performance, serum cytokine and intestinal immune level in weanling piglets. These results demonstrate that DON has immunotoxicity to the piglets