【作者】 万恩怀；

【导师】 邓俊良；

【作者基本信息】 四川农业大学 ， 临床兽医学， 2006， 硕士

【摘要】 试验选用200只一日龄铁脚麻肉仔鸡，采用单因子多水平随机分组实验设计来研究马杜霉素对肉仔鸡免疫功能的影响。将铁脚麻肉仔鸡分为数量相等、体重均匀的4个组，每组5个重复，每个重复10只鸡。肉仔鸡采用笼养，恒温控制，自然光照，自由采食，自由饮水。根据现有文献资料报道的马杜霉素对肉仔鸡的安全剂量和最低毒性剂量，从11日龄起在玉米一豆粕型基础日粮的基础上分别添加不同剂量的马杜霉素，使日粮中马杜霉素分别达到0、5.0、7.5、10.0mg／kg，连续饲喂4周，实验期为7周。观察测定各组雏鸡临床表现、生产性能、免疫器官指数、免疫器官组织病理学变化、红细胞补体受体花环率及免疫复合花环率、外周血淋巴细胞转化能力、新城疫抗体效价及脾脏淋巴细胞周期，判断不同剂量马杜霉素对肉仔鸡免疫功能的影响效应及其规律。试验结果表明：1．5.0mg／kg饲料剂量马杜霉素饲喂铁脚麻肉仔鸡，连续使用3周是安全的；7.5～10.0mg／kg饲料剂量马杜霉素饲喂铁脚麻肉仔鸡可导致中毒，但并不引起典型的中毒症状。2．5.0mg／kg饲料剂量马杜霉素前3周对铁脚麻肉仔鸡生产性能和免疫功能有一定促进作用，但3周后呈现一定的抑制作用。3．7.5mg／kg饲料剂量马杜霉素饲喂铁脚麻肉仔鸡1周可降低其饲料利用率；饲喂3周可抑制免疫器官生长发育及红细胞免疫功能；饲喂4周可抑制体液免疫功能；停药后1周内可抑制外周血淋巴细胞免疫功能。4．10.0mg／kg饲料剂量马杜霉素饲喂铁脚麻肉仔鸡1周可降低其饲料利用率，损害免疫器官；饲喂2周可抑制免疫器官生长发育；饲喂3周可抑制红细胞免疫功能；饲喂4周可抑制体液免疫功能和外周血淋巴细胞免疫功能。5．马杜霉素对铁脚麻肉仔鸡生产性能和免疫功能的抑制作用随用药剂量升高和用药时间延长而加重；对生产性能、免疫器官生长发育及细胞免疫功能的抑制作用能持续至停药后1周，上述指标能在停药后3周内逐步恢复正常。更多还原

【Abstract】 An experiment was conducted with 4×1 factorial design to study the effect of dietary maduramicin on immunologic function of broilers. 200 day-old healthy TieJiaoMa broilers with an equal weight were assigned to 4 groups with 5 replicates at random, each having 10 chicks. The broilers were reared in cages. The house was controlled in constant temperature and natural exposure. The broilers were allowed accessing to the food and water at liberty. In trial, the broilers were fed with a basal corn-soybean meal diet supplemented with 0, 5.0, 7.5 mg/kg and 10.0 mg/kg maduramicin for 4 weeks, according to the secure dose and lowest toxicity dose in existence. The trial was carried through when the broilers were 11 days old and persisted 7 weeks. Finally, the results of the trial were received, by observing or determining the symptom, growth performance, indexes of immune organ, histopathology change of immune organ, percentage of the erythrocyte complement receptor rosette, percentage of erythrocyte immune compound rosette, lymphocyte transformation, antibody titer of the ND and lymphocyte cycle of the spleen. The experiment results indicated that: 1. The growth performance and immunologic function of the TieJiaoMa broilers were advanced in the former 3 weeks of the trial and then were checked gently by 5.0mg/kg maduramicin when compared with the control group. 2. The forage availability of the TieJiaoMa broilers was depressed in 1^st week of the trial and the immunologic function of the TieJiaoMa broilers was checked from 3^rd to 5^th weeks of the trial by 7.5 mg/kg maduramicin when compared with the control group. 3. The forage availability of the TieJiaoMa broilers was depressed in 1^st week of the trial and the immunologic function of the TieJiaoMa broilers was checked from 2^nd to 5^th weeks of the trial by 10.0 mg/kg maduramicin when compared with the control group. 4. It was safety to feed the TieJiaoMa broilers with a diet supplemented with 5.0mg/kg maduramicin for 3 weeks, and the TieJiaoMa broilers could be poisoned when fed with a diet supplemented with 7.5-10.0mg/kg maduramicin, but there was no typical toxic symptom. 5. The depressant更多还原