【作者】 刘颖；

【导师】 吕洪飞；

【作者基本信息】 浙江师范大学 ， 植物学， 2010， 硕士

【摘要】 贯叶连翘(Hypericum perforatum)是藤黄科(Guttiferae)金丝桃属(Hypericum)多年生草本植物,是一种传统草药,广泛应用于欧洲,西亚和北非。自古以来,贯叶连翘通常用来抗抑郁症。然而贯叶连翘含有的多种成分还具有抗病毒、抗菌、抗氧化等活性。特别是最近一些研究表明贯叶连翘可以降低动物血清中甘油三酯和总胆固醇含量。国内外将贯叶连翘作为动物饲料添加剂的研究并不多见,生理生化和免疫功能等方面的研究少有报道。本研究将A、B、C、D、E五个添加水平(A＜D＜C＜D＜E)的贯叶连翘提取物添加于鸡饲料中。经过一段时间的饲喂,定期检测血液和鸡蛋中的一系列生理生化指标,考察贯叶连翘对鸡血液生理、血清生化、生产性能、鸡蛋品质、鸡蛋生化指标、蛋清溶菌酶等相关指标的影响。另外,在首次和第二次H5亚型禽流感疫苗免疫后的7天内,将A、C、D、E四个添加水平的贯叶连翘提取物添加于鸡饲料中,定期检测H5亚型禽流感疫苗免疫效果.最终,筛选出最佳的贯叶连翘添加比例和饲喂方法,以期提高鸡的生产性能和防治禽流感能力,为贯叶连翘饲料添加剂的生产应用提供理论依据。主要研究结果如下：1、D添加水平的两组鸡血清中白蛋白、谷丙转氨酶、碱性磷酸酶等肝功能指标和血肌酐与对照组相比无显著差异(P＞0.05),血液中白细胞数和淋巴细胞百分率明显提高(P<0.05)，从而提高了非特异性免疫能力。另外,鸡血清溶菌酶活力明显提高(P＜0.05),从而增强了抵御病菌感染的能力。2、饲喂贯叶连翘4周后,与对照组相比,E添加水平增加了(P<0.05)蛋重,降低了(P<0.05)料蛋比(耗料重/蛋重)和蛋壳厚度；D和E添加水平,降低(P<0.05)蛋黄总胆固醇和丙二醛(MDA)含量,提高(P<0.05)蛋清溶菌酶活力,一定程度上提高(P>0.05)超氧化物歧化酶(SOD)活力,但无显著性差异。D、E两个添加水平对产蛋率都无影响(P>0.05)。此外,B、C、D三个添加水平都显著降低(P<0.05)蛋黄甘油三酸脂含量。研究结果表明,在饲喂贯叶连翘4周时间内,除E添加水平能使蛋壳厚度降低之外,其它各添加水平均未引起蛋品质的降低。3、D水平添加量的贯叶连翘能使鸡血清中H5亚型禽流感病毒抗体水平在首免和二免后的抗体高峰期提高9.82%、30.63%；使H5亚型禽流感病毒Re-4株抗体效价在首免和二免后的抗体高峰期提高11.27%、27.40%；使H5亚型禽流感病毒Re-5株抗体效价在首免和二免后一直高于对照组,特别是在首次、二次免疫后的抗体高峰期分别提高7.70%、16.44%。综上所述,在D添加水平下,贯叶连翘对鸡的生理功能、生产性能和鸡蛋品质无不良影响,提高鸡的非特异性免疫作用和鸡蛋的氧化稳定性,同时降低蛋黄总胆固醇和甘油三酯含量；另外,D水平添加量的贯叶连翘能够有效增强H5亚型禽流感疫苗的免疫效果,维持首次免疫和二次免疫后的抗体水平长期高于对照组。因此,可以得出结论,贯叶连翘在鸡饲料中最佳的添加水平是D；另外,贯叶连翘能够在保证鸡生理安全的前提下,提高蛋鸡生产性能和鸡防治H5亚型禽流感能力,提高鸡蛋抗氧化性能,降低鸡蛋中脂类含量,从而提高养殖场的经济效益,产出的鸡蛋也更加有益于人体健康。更多还原

【Abstract】 Hypericum perforatum is a perennial herb in the Guttiferae family native to Europe, western Asia, and northern Africa. It has traditionally been applied as a medicinal plant to treat antidepressant. Currently, it has been found that various ingredients contained in Hypericum perforatum have anti-virus, anti-bacterial, anti-oxidation activities, especially can lower the serum total cholesterol and triglyceride contents in animals.Inspite of those above, the study on appling Hypericum perforatum as feed additives for animals has not been reported both at home and abroad. The study was few on the effects of Hypericum perforatum on physiological and immune actions in layers. In this study, several levels (A＜D＜C＜D＜E) of Hypericum perforatum extract were added to the layers’diets. Afterthat, the effects of it were studied on physiological and biochemical indexes in blood, production performances and the level of antibody to H5 subtype avian influenza in layers. Finally, the best level of Hypericum perforatum added into diets was filtered out, in order to apply it as layers’additive and enhance the production performances and ability to prevent avian influenza. The results are as following:1. The contents of albumin, alanine aminotransferase, and alkaline phosphatase in serum of D level groups had no significant difference (P＞0.05) compared with the control group. White blood cell count and lymphocyte percentage significantly increased (P＜0.05) in the two level groups, thus Hypericum perforatum can enhance the non-specific immunity. In addition, the lysozyme activity in serum was significantly increased (P＜0.05), increasing the ability to resist infection.2. After feding with Hypericum perforatum for 4 weeks, compared with the control group, E level had increased (P＜0.05) egg weight, reduced (P＜0.05) feed conversion ratio (feed consumption weight/egg weight) and egg shell thickness. D and E levels had decreased (P＜0.05)total cholesterol and malondialdehyde (MDA) content egg yolk, increased (P＜0.05) egg white lysozyme, improve superoxide dismutase (SOD) activity to some extent, but with no significant difference (P＞0.05). D and E levels have no effect on egg production rate (P＞0.05). In addition, B, C and D levels significantly lowered (P＜0.05) the content of triglycerides egg yolk. The results also showed that the egg qualities were not influenced during 4 weeks feeding except that the E level can reduce the thickness of eggshell.3. D additional level of Hypericum perforatum can increased the level of antibody to H5 subtype avian influenza in serum by 9.82% and 30.63% respectively in the two antibody peaks after first and second immunizations. It can increased Re-4 polyclonal H5 subtype avian influenza antibody titer in serum by 11.27% and 27.40% respectively in the two antibody peaks after first and second immunizations. Re-5 polyclonal H5 subtype avian influenza antibody titer in D level group were always higher than control after the twice immunizations, particularly the antibody titer was increased by 7.70% and 16.44% respectively in antibody peaks.To sum up, D level of Hypericum perforatum added into diets had no adverse effects on the physiological function of layers and egg qualitys. It can enhance the non-specific immunity, production performance of layers and egg oxidation resistance,while it can reduced total cholesterol and triglyceride contents in egg yolks. In addition, D level of Hypericum perforatum added into diets can effectively enhance the action of H5 subtype avian influenza vaccine with higher antibody levels after the first and secondary immunization. Therefore, it can be concluded that the best level of Hypericum perforatum added into diets is D. Moreover, Hypericum perforatum can improve the production performance of layers, the prevention against H5 subtype avian influenza and the oxidation resistance of eggs, while reduce lipid content of eggs, without affecting the physical safety of layers. In a word, the Hypericum perforatum may enhance the profits of the farm, and be beneficial to human health.更多还原