【作者】 周艳；

【导师】 方静； 李英伦；

【作者基本信息】 四川农业大学 ， 基础兽医学， 2007， 硕士

【摘要】 目的：研究硫酸粘杆菌素对雏鸡的免疫器官重量、指数、组织结构及红细胞免疫功能的影响，为家禽生产中合理添加使用硫酸粘杆菌素提供一定的理论依据。方法：选用一日龄艾维茵肉鸡160只，试验分为五组，Ⅰ组（基础日粮）、Ⅱ组（基础日粮+20mg／kg硫酸粘杆菌素）、Ⅲ组（基础日粮+40mg／kg硫酸粘杆菌素）、Ⅳ组（基础日粮+60mg／kg硫酸粘杆菌素）和Ⅴ组（基础日粮+80mg／kg硫酸粘杆菌素），试验期6周。每周取胸腺、法氏囊和脾，称重，Bouin氏液固定，石蜡切片，镜检，摄像；测定红细胞C₃bR和IC花环率；42日龄取Ⅰ、Ⅴ组胸腺、法氏囊和脾制作透射电镜切片。结果：与对照组比较，Ⅲ、Ⅳ、Ⅴ组免疫器官绝对重量及其指数明显降低（P＜0.05或P＜0.01）；28～42日龄Ⅲ、Ⅳ、Ⅴ组胸腺皮质宽度明显减少（P＜0.05或P＜0.01）；21～42日龄Ⅴ组和28～42日龄Ⅲ、Ⅳ组法氏囊淋巴滤泡及其皮、髓质面积明显减小（P＜0.05或P＜0.01）。脾小结和脾动脉周围淋巴鞘面积的变化规律与法氏囊淋巴滤泡面积的变化规律相似。胸腺、法氏囊中淋巴细胞和网状细胞的核膜局部断裂，粗面内质网肿胀；脾脏中浆细胞线粒体嵴断裂，粗面内质网肿胀。随日龄和剂量增加，雏鸡红细胞C₃bR和IC花环率均下降，其中以60mg／kg和80mg／kg组最为明显。结论：不同剂量的硫酸粘杆菌素均可不同程度导致雏鸡免疫器官绝对重量及其指数和红细胞免疫功能下降，并且表现出一定的剂量—时间—效应关系。持续添加80mg／kg硫酸粘杆菌素可使免疫器官中淋巴细胞、网状细胞和浆细胞受损。建议在肉用雏鸡的生产中添加硫酸粘杆菌素剂量最好低于40mg／kg，禁止使用60、80mg／kg硫酸粘杆菌素添加剂量。更多还原

【Abstract】 Objective: To study the effect of dietary colistin sulfate on the weight, the index and the tissue structure of immune organs, and erythrocyte immunity function. It would provide a theoretical basis to add colistin sulfate reasonably in poultry production. Methods: 160 one-day-old Avian chickens were randomly divided into five groups, and fed on diets as follow: basic diet （Colistin sulfate 0mg/kg, controlⅠ） and different dose diets （Colistin sulfate 20 mg/kgⅡ, 40mg/kgⅢ, 60mg/kgⅣ, 80mg/kgⅤ） respectively for six weeks. The thymus, bursa of fabricius and spleen were weighed and fixed in Bouin liquid. Afterwards the tissues were made into paraffin section and stained with HE, then observed with microscope and photographed. The erythrocyte C₃bR and IC ratios were tested respectively each week. The thymus, bursa of fabricius and spleen were made into electron microscopic section in groupⅠandⅤat 42 days age. Results: The absolute weights and the indices of immune organs in groupⅢ,Ⅳ,Ⅴdropped obviously compared with those of groupⅠ（P＜0.05 or P＜0.01）. Microscopically, the widths of thymic in groupⅢ,Ⅳ,Ⅴdecreased greatly compared with those of groupⅠin 28～42 days age （P＜0.05 or P＜0.01）. The areas of lymph follicle, lymph cortex and lymph medullary in bursa of fabricius, the areas of splenic corpuscle and periarterial lymphatic sheath in spleen in groupⅤdecreased remarkably compared with those of groupⅠin 21～42 days age（P＜0.05 or P＜0.01）, so did those of groupⅢandⅣin 28～42 days age （P＜0.05 or P＜0.01）. Ultrastructurally, the nuclear membranes of lymphocyte and reticular cell were broken; the rough-surfaced endoplasmic of lymphocyte, reticular cell and plasma cell were swelling in immune organs; the crista of mitochondrion was broken in plasma cell of spleen. Meanwhile, the erythrocyte C₃bR and IC ratios decreased markedly as the chicken grew and colistin sulfate dosage increased, especially in 60mg/kg and 80mg/kg groups when compared with those of control group. Conclusions: This study indicates that the absolute weights and indices of immune organs and the erythrocyte immunity functions were decreased in various degrees by different doses of colistin sulfate, which shows both time and dose dependence. Lymphocyte and reticular cell of immune organ were broken in the groupⅤ. It’s suggested that the dose of colistin sulfate should be lower than 40mg/kg in the chicken feeds, and 60, 80mg/kg colistin sulfate should be forbidden in the chicken feeds.更多还原