本试验旨在研究不同水平维生素D3对丝毛乌骨鸡组织中β-防御素（AVBDs)基因表达的调控。采用实时荧光定量PCR方法检测饲喂不同水平（800、1 600、3 200和6 400 IU/kg）维生素D3对丝毛乌骨鸡胸腺、十二指肠、空肠、回肠、盲肠和法氏囊中3个β-防御素（AVBD-1、AVBD-5和GAL-1）基因表达水平的影响。结果表明：3个β-防御素基因在6个组织中均有表达，其中乌骨鸡AVBD-1和GAL-1基因的最高表达水平都在采食了3 200 IU/kg维生素D3时的空肠；AVBD-5基因的最高表达水平在采食了1 600 IU/kg 维生素D3时的十二指肠；在依次采食维生素D3 800、1 600、3 200和6 400 IU/kg的乌骨鸡组织中，3个β-防御素基因都存在先升后降的表达趋势。结果表明，β-防御素基因在同一组织的表达水平与维生素D3饲喂水平存在剂量关系，适宜的维生素D3饲喂水平能上调这3个β-防御素基因在乌骨鸡组织中的表达量。

To study vitamin D3 regulation of β-defensins genes in the different tissues of Silky Fowl, real-time quantitative PCR method was used to analyze the expression of AVBD-1, GAL-1 and AVBD-5 in thymus, duodenum, jejunum, ileum, cecum and bursa F. of Silky Fowl with fed different levels of vitamin D3 (800, 1 600, 3 200 and 6 400 IU/kg). The results showed that three β-defensins gene expressions were found in six tissues of Silky Fowl, and the highest gene expression levels of AVBD-1 and GAL-1 were both in jejunum of Silky Fowl which fed 3 200 IU vitamin D3; the highest gene expression level of AVBD-5 in duodenum of Silky Fowl was in group fed 1 600 IU vitamin D3; in the tissues of Silky Fowl fed 800, 1 600, 3 200 and 6 400 IU vitamin D3 per kg diet, respectively, expression of the three AVBDs genes were directly up-regulated, then rapidly down-regulated. The results indicated that a dose-dependent manner that the gene expression levels in same tissues and vitamin D3 supplementary levels in diet of Silky Fowl was seen, and the suitable level of vitamin D3 could directly up-regulate the gene expression of β-defensins in tissues of Silky Fowl.