中文摘要：

【目的】探讨防御素AvBD13对雏鸡体液免疫的影响。【方法】雏鸡的饮水从1日龄添加AvBD13（1μg·ml^-1）,分别于1、4、7、10、17日龄随机采集雏鸡的血液、脾脏、法氏囊、十二指肠、空肠和盲肠。分别采用MTT方法、ELISA方法和免疫组织化学方法检测外周血液B淋巴细胞增殖功能、血清的免疫球蛋白含量和免疫器官、肠道的抗体生成细胞数量。【结果】与对照组比较,AvBD13明显提高了4～10日龄雏鸡血清中IgG和10～17日龄雏鸡血清中IgM含量（P〈0.05）,提高了4～7日龄雏鸡脾脏红髓和法氏囊中IgG和IgM生成细胞数量（P〈0.05）。AvBD13组雏鸡肠道的IgG和IgM生成细胞的数量在4～10日龄高于对照组雏鸡,但无统计学差异（P〉0.05）,仅盲肠扁桃体的IgA生成细胞数量在4日龄明显高于对照组雏鸡（P〈0.05）。【结论】雏鸡口服AvBD13能够明显提高其系统体液免疫,对肠道黏膜体液免疫提高较小,AvBD13对免疫器官和局部黏膜免疫组织具有一定的选择特异性。

英文摘要：

【Objective】 The aim of this study was to investigate the effect of AvBD13 on the humoral immune response of chicken. 【Method】 In the treatment group chickens received drinking water supplemented with AvBD13 （1 μg·ml^-1） right after hatching. Samples of blood,bursa of Fabricus,spleen and intestine were taken at day 1,4,7,10 and 17 of experiment. B lymphocyte proliferation in peripheral blood stimulated by mitogen,the content of immunoglobulin in serum,antibody-forming cells in immune organ and intestine were measured by MTT,ELISA or immunohistochemistry methods. 【Result】 AvBD13 supplementation enhanced the content of IgG and IgM in serum from day 4-10 and day 10-17,respectively （P〈0.05）,IgM-forming cells in bursa of Fabricus and spleen at the age of 4-7 days （P〈0.05）. In addition,AvBD13 could slightly enhance the number of IgM-forming cells and IgG-forming cells in intestine at day 4 to 10,but had no significant difference （P〉0.05）,AvBD13 only enhanced the cecal tonsils diffuse area IgA-forming cells at day 4 （P〈0.05）. 【Conclusion】 These results suggested that AvBD13 could greatly enhance systemic humoral immune responses and slightly enhance mucosal humoral immune responses,which maybe the reason of tissue specific effect of defensins.