Despite Withania somnifera (WS), stimulating effects have been investigated on many animal species, its role on lipid profile and intestinal histomorphology in healthy animals, and its modulating role on pro-inflammatory cytokines following infection in fish are yet scarce. In this context, lipid profile, liver, and intestinal histomorphology were measured in Nile tilapia fed with a basal diet or diets containing 2.5 and 5% of supplementary WS for 60 days. Besides, cytokines response was measured at 1, 3,7, and 14 days following Streptococcus iniae (S. iniae) infection after the feeding trial. All lipid profile parameters were nominally lowered, excluding high-density lipoprotein (HDL) that exhibited a significant increase in WS 5% group compared to other groups. Improved gut health integrity was observed, especially in WS 5% group in terms of increased goblet cell numbers, villous height, the width of lamina propria in all parts of the intestine, and a decrease in the diameter of the intestinal lumen of the distal intestine only. A significant down-regulation in the mRNA transcript level of cytokine genes (interleukin 1β/IL-1β, tumor necrosis factor α/TNFα, and interleukin 6/IL-6) was demonstrated in the kidney and spleen of WS-supplemented groups following S. iniae infection compared with the control infected (positive control/PC) group. Our findings give new insights for the potential roles of WS dietary inclusion not only on lipid profile and intestinal health integrity improvement in healthy fish under normal rearing but also as a prophylactic against the infection. Thus, WS can be incorporated as a promising nutraceutical in aquaculture.

尽管有Withania somnifera（WS），但对许多动物种类，其在健康动物中对脂质谱和肠道组织形态学的作用以及对鱼感染后促炎性细胞因子的调控作用的刺激作用尚未进行研究。在这种情况下，在尼罗罗非鱼中饲喂基础日粮或含有2.5％和5％补充WS的日粮60天，测量其脂质分布，肝脏和肠道组织形态。此外，在喂养试验后，在感染链球菌感染后的1、3、7和14天测量细胞因子应答。除了高密度脂蛋白外，所有脂质谱参数均已名义降低（HDL）与其他组相比在WS 5％组中表现出显着增加。观察到肠道健康完整性得到改善，特别是在WS 5％组中，就杯状细胞数量增加，绒毛高度，肠道所有部位固有层的宽度以及远端肠的肠腔直径减小而言，尤其如此只要。在S补充后WS补充组的肾脏和脾脏中，细胞因子基因（白介素1β/IL-1β，肿瘤坏死因子α/TNFα和白介素6 / IL-6）的mRNA转录水平显着下调。。海豚链球菌感染与感染对照（阳性对照/ PC）组相比。我们的发现提供了有关...的潜在作用的新见解WS饮食中的包容不仅在正常饲养下健康鱼类的脂质分布和肠道健康完整性改善方面，而且还可以预防感染。因此，WS可以作为有前途的营养保健品纳入水产养殖。