This study was conducted to assess the comparative effects of a mixed herbal extract (MHE) containing Ocimum sanctum, Withania somnifera, Emblica officinalis, Tinospora cordifolia, Mangifera indica, and Asphaltum (shilajit) on infectious bursal disease virus (IBDV)-vaccinated (VAC) chickens infected with IBDV and avian influenza virus (AIV) H9N2. The experiment included three groups (G1-G3): G1, the negative control group; G2, the VAC + challenged (Ch) group; and G3, the VAC + Ch + MHE group. MHE was orally administered continuously for 5 weeks post-vaccination (PV) with IBDV at 12 days of age, and the chicks were simultaneously challenged with virulent IBDV (intraocularly) and AIV H9N2 (intranasally) at 21 days PV. Blood and tissue samples as well as tracheal and cloacal swabs were gathered at different times PV and post-challenge. Immunological and haematological parameters, histopathological lesions, relative organ weights and final live weights revealed significant differences (P ≤ 0.05) between G2 and G3 groups. Furthermore, in the G3 group, the protection rates, ELISA and HI titers and CD4+/CD8+ ratio were significantly increased, whereas viral shedding titers and the heterophil/lymphocyte ratio were decreased. In conclusion, the oral administration of the mixed herbal extract for 5 weeks can stimulate the immune response to IBDV vaccination and relieves the pathogenicity of an AIV H9N2 and IBDV co-infection in chickens.

进行该研究以评估混合草药提取物（MHE）含有的比较效果圣罗勒，催眠睡茄，余甘厚朴，叶青牛胆，芒果，以及沥青（shilajit黄）感染IBDV和禽流感病毒（AIV）H9N2的传染性法氏囊病病毒（IBDV）疫苗接种（VAC）鸡。实验包括三组（G1-G3）：G1，阴性对照组； G1，阴性对照组。G2，VAC +挑战（Ch）组；和G3，即VAC + Ch + MHE组。在接种后（PV）于12日龄连续5周给MHE口服（PV），在21天PV时用强毒IBDV（眼内）和AIV H9N2（鼻内）攻击小鸡。在不同时间PV和攻击后收集血液和组织样本以及气管和泄殖腔拭子。免疫学和血液学参数，组织病理学损害，相对器官重量和最终活重显示出显着差异（P≤0.05）在G2和G3组之间。此外，G3组的保护率，ELISA和HI滴度以及CD4 + / CD8 +比值显着增加，而病毒的滴度和异源性/淋巴细胞比值则降低。总之，口服混合草药提取物5周可以刺激对IBDV疫苗的免疫反应，并减轻AIV H9N2和IBDV共同感染鸡的致病性。