多糖和益生菌对暗纹东方免疫功能的调节

Immunoregulation of polysaccharide and probiotics on Fugu obscurus

为了研究多糖、益生菌等免疫增强剂对暗纹东方的免疫调节作用,本试验随机将暗纹东方[(167.8±24.4)g]分为6组。其中阳性对照组为免疫功能低下组,投喂基础饲料、注射8mg.kg-1体重的环磷酰胺;阴性对照组为免疫功能正常组,投喂基础饲料、注射生理盐水;其余试验组分别用含有0.2%壳聚糖、0.1%益生菌、甘露聚糖与益生菌混合物、壳聚糖与益生菌混合物的饲料连续投喂30d,同时注射8mg.kg-1体重的环磷酰胺。测定各组暗纹东方的外周血白细胞数量及吞噬活性、肝胰脏溶菌酶活性、头肾与脾脏淋巴细胞转化、头肾与脾脏IFN-α含量、头肾与脾脏IgM含量进行免疫功能的比较。结果表明,多糖和益生菌对免疫功能低下的暗纹东方具有免疫调节作用。所检测的各项免疫指标均有不同程度的恢复,或处于免疫功能正常与环磷酰胺所致免疫抑制水平之间,或恢复至正常水平或超过正常水平。不同免疫增强剂对同一种免疫器官、免疫细胞或免疫分子的调节作用或同一种免疫增强剂对不同的免疫器官或免疫细胞或免疫分子的调节作用均存在差异。从整体效果看,在所研究的4种免疫增强剂中,甘露聚糖与益生菌混合物的免疫调节作用最弱。

In order to study immunoregulation role of dietarypolysaccharide and probiotics, the fish Fugu obscurus weighing （ 167.8 ± 24.4） g were randomly divided into 6 groups. The immunosuppression control group（positive control） was given an intraperitoneal dose of 8 mg· kg^- 1 body weight cyclophosphamide（Cy） every 5 days for three times and fed on the basal diet , and the normal control group（ negative control） was injected with 0.9% NaCl solution and fed on the basal diet according to the same procedure. The other 4 groups Were intraperitoneaUy injected of 8 mg·kg^-1 .body weight Cy every 5 days for three times and fed on basal diets supplemented 0.2% chitosan, 0.1% probiotics, mixture of mannan ohgosaccharide, hadde and probiotics, mixture of chitosan and probiotics for 30 d respectively. The number of white cells in peripfieral blood, phagocytic percentage of the peripheral blood leucocytes, activity of lysozyme in hepatopanereas, proliferation responses of T and B lymphocytes from spleen and head kidney stimulated by PHA and LPS, IgM and IFN-α content from super-natants generated from spleen and bead kidney cultivated in vitro were determined. The dose of 8 mg·kg^-1 body weight Cy depressed the non-specific immunity of the fish, and all the above four immunoenhaneers had potential immunomodulationg role on the immunodepressed, fish. During the period of test, every immunity parameter examined could return to the level between depressed level and normal level or to the normal level, even exceeding the normal level. It seemed likely that different immunoenhancers may have different ways in stimulating immune organs, immune cells or immune molecules, and same immunoenhancer may also have different effects upon different immune organs, different immune cells and immune molecules. Nevertheless, according to the overall effect, the.mixture of mannan ollgosaccharide had the least immunomodulatory effect among the four immunoenhancers.