【作者】 计慧琴；

【导师】 张石蕊； 王丙云；

【作者基本信息】 湖南农业大学 ， 畜牧养殖， 2004， 硕士

【摘要】 本文研究了三肽囊素(BS)对环磷酰胺(CP)诱导的墟岗黄鸡免疫抑制的阻断作用及机制，旨在进一步证实三肽囊素的免疫增强作用，为三肽囊素作为一种新型免疫增强剂提供实验依据。 180只一日龄墟岗黄母鸡随机分成对照组(Ⅰ)、环磷酰胺组(Ⅱ)、三肽囊素+环磷酰胺组(Ⅲ)和三肽囊素组(Ⅳ)四个组，每组设三个重复，每个重复15只鸡．在第4日龄和第7日龄时，第Ⅲ、第Ⅳ组每只鸡腿部肌肉分别注射0.01mg／kg体重的BS，同时第Ⅰ、第Ⅱ组鸡分别注射等量的生理盐水；第10日龄时，第Ⅱ组、第Ⅲ组分别注射40mg／kg体重的CP，同时第Ⅰ、第Ⅳ组分别注射等量的生理盐水。通过检测鸡只体重以及免疫功能的变化，研究BS和CP对鸡生长性能和免疫功能的影响。结果表明： 1．在试验开始时，各组鸡体重的差异并不显著。14日龄时环磷酰胺组和环磷酰胺+三肽囊素组显著低于对照组和三肽囊素组。28日龄时，环磷酰胺组和环磷酰胺+三肽囊素组仍显著低于对照组和三肽囊素组，而三肽囊素组显著高于其它三个组。56日龄时，环磷酰胺十三肽囊素组鸡的生长速度逐渐恢复，且显著高于环磷酰胺组。结果表明BS对鸡的体重增加有一定的促进作用，CP对鸡的生长有明显的抑制作用，BS可部分拮抗这种抑制作用。 在整个试验期间，三肽囊素组的饲料转化率(料肉比)均低于其它三组，环磷酰胺组显著高于其它三组，环磷酰胺+三肽囊素组低于环磷酰胺组，但高于三肽囊素组和对照组，表明注射BS可以提高饲料报酬，且可部分拮抗环磷酰胺降低饲料报酬的作用。 2．Ⅱ组和Ⅲ组鸡的法氏囊指数、胸腺指数和脾脏指数低于或显著低于Ⅰ和Ⅳ组，且以Ⅱ组最低。Ⅱ组鸡的胸腺小体体积小且数量少；法氏囊的淋巴滤泡明显缩小，皮质和髓质的界限不清，淋巴细胞明显减少或消失；脾脏脾小体比对照组的要小，生发中心不明显。Ⅲ组鸡的胸腺小体和脾小体数量多于Ⅱ组，法氏囊皮质和髓质界限清楚，淋巴细胞数多于Ⅱ组。Ⅳ组鸡的胸腺细胞、胸腺小体以及法氏囊内淋巴细胞明显增多，在脾脏中可见较多的脾小体，且随着日龄的增长生发中心增多。结果提示：CP可明显抑制法氏囊、胸腺和脾脏的发育，损伤免疫器官的组织结构，而BS可阻断CP的抑制作用。 3．环磷酰胺组和三肽囊素+环磷酰胺组红细胞总数在56日龄时显著低于对照组和三肽囊素组，且以环磷酰胺组最低。14日龄和35日龄时，环磷酰胺组的RBC-R1花环率显著低于或低于其它三组，而RBC-IC花环率却高于其它三组。提示，三肤囊素可增加红细胞数量，提高红细胞免疫功能，且可部分抵抗环磷酞胺抑制红细胞免疫功能的作用。4.在14日龄时，n组鸡血浆中Y一球蛋白含量显著低于其它三组(P<0 .05)。在35日龄时，n组仍显著低于其它三组，而W组显著高于其它三组。在56日龄时，IV组血浆中Y一球蛋白含量仍显著高于其它三组(P<0.05)，而其它三组之间差异不显著(P>.05)。结果表明，CP可显著抑制鸡的体液免疫功能，而BS可显著提高体液免疫作用。5.在14、35和56日龄时W组外周血液淋巴细胞增殖转化明显高于其他三组，且差异显著(P《0.05)。在14、35日和56龄时，n组血浆IL一2含量显著低于其它三组，且差异显著(P《0.05)，而m组、W组与I组差异不显著。结果表明CP可显著抑制鸡的细胞免疫功能，而BS可显著增强鸡的细胞免疫功能。6.利用末端脱氧核营酸转移酶介导的dTUP缺口末端标记法(TUNEL)对三肤囊素和环磷酞胺后不同日龄鸡的免疫器官细胞凋亡进行计数。结果表明:各日龄段，环磷酞胺组凋亡细胞数均高于或显著高于其它三组，而三肤囊素组的细胞凋亡数最低。显示:三肤囊素可减少免疫细胞的凋亡。关键词:三肤囊素环磷酞胺鸡免疫功能细胞调亡更多还原

【Abstract】 The interdiction effects of Bursin on the immunosuppress of Yue yellow broilers induced by CP and its’ functional mechanism were studied in this paper in order to affirm the immunopotentiation of BS and provide experimental evidence for its application to immunopotentiator.180 female Yue yellow broilers were randomly divided into four groups with per group had three replicates, and every replicate allotted 15 broilers. Group III and IV received S.C jnjection BS at dose of 0.01mg/Kg on day 4 and day 7 respectively, while group I and II received isometric physiological saline. On day 10, group II and III received CP at dose of 40mg/Kg; while group I and IV received isometric physiological saline respectively.The results shown as follows:1. There was not distinct difference of the average body weight ( ABW) in each group at day 14. While the growth performance of group II and III was markedly restrained on day 28 and 42. On day 56, the ABM of group III increased gradually and was higher than group I. However, the growth performance of group II was still restrained. The results suggested that BS had stimulative effects while CP had significantly suppressive effects on growth performance and the suppressive effects of CP were partly reversed by BS.2. The organ index of bursa of Fabricius, thymus and spleen of group II and III was lower or significantly lower than group I and IV, and group II was the lowest. In group II, the volume of thymus corpuscles was small and the number of thymus corpuscles was few; the lymphoid follicle of bursa of Fabricius was atrophied; the sideline between cortex and medulla was indistinct; the number of lymphocytes was obviously reduced or disappeared; the volume of spleen corpuscle was smaller than control group (group I), and the germinal center was not distinct. In group III, thenumber of thymus corpuscles, spleen corpuscle and lymphocytes was more than group II; and the sideline between cortex and medulla was clear. As for group IV, the number of thymus corpuscles, spleen corpuscle and lymphocytes obviously increased; induced by CP.3. The E-C3bR rate of group III and I was 6.8 3 ±Considerable spleen corpuscle was observed in spleen; and the germinal center was enlarged with the increase of age. The results suggested that CP significantly suppressive effects on the development of bursa of Fabricius, thymus and spleen, while BS could interdict the suppressive effects 0.66% and 6.33±0.44% respectively, and there was a significant difference between the two groups (P<0.05) . The E-IC rosette rates rate of group was significantly higher than group III (P<0.05). The results suggested that BS interdicted the suppressive effect on red blood cell immunity induced by CP.4.The concentration of plasma v -globulins of group II was significantly lower than other groups on day 14 (P<0.05) .On day 35, the group II was still significantly lower than other groups; however, the group IV was significantly higher than other groups. On day 56, the group IV was still significantly higher than other groups (P<0.05) ,while no significant difference was observed in other three groups. The results suggested that CP had the distinctly suppressive effects while BS has the distinctly stimulative effects on humoral immunity of Yue yellow broilers.5. On day 14,35 and 56 , the efficiency of proliferation and transformation of lymphocytes of peripheral blood of group IV was remarkably higher than other groups respectively (P<0.05) . As for the concentration of plasma IL-2, group II was significantly lower than other groups (P<0.05) ,while there was no significant difference between group III, IV and group I. The results suggested that CP had the distinctly suppressive effects while BS has the distinctly stimulative effects on cellular immunity of Yue yellow broilers.6. Apoptosis of immune organ was counted by TUNEL that conducted by terminal deoxynucleotidyl transferase after treated to different age of Yue yellow broilers. The number of immune organ apoptosis of group II was significantly higher than group I(P<0.05)更多还原