The effect of dietary grape (Vitis vinifera) seed extract (GSE) on growth performance and mucosal immune parameters in rainbow trout (Oncorhynchus mykiss) fry was studied. Fish (1.3 g mean weight) were randomly distributed in nine tanks (15 fish per tank) and fed diets containing GSE at 0 (control), 100, and 200 mg kg⁻¹for 60 days. The results showed that growth parameters were enhanced in both treatment groups compared to the control group. Histological examination of fish skin showed higher epidermis thickness, goblet cell density, and volume density in the GSE groups compared to the values of the control group. Furthermore, the villus height, goblet cell density, and intraepithelial lymphocytes were increased in the fish intestine in those fish fed GSE, with respect to control fish. Feeding fish with low dose of GSE (100 mg kg⁻¹) up-regulated the expression of some immune-relevant genes, including complement component 3 (C3), lysozyme (Lys), omDB-3, interferon gamma (IFN-γ), and tumor necrosis factor-α (TNF-α) in different mucosal tissues. However, feeding fish the high dose of GSE (200 mg kg⁻¹) mostly enhanced expression of these genes in the skin. Besides, skin mucus of fish fed GSE showed bactericidal activity against Yersinia ruckeri. It was concluded that GSE, especially at 100 mg kg⁻¹, modulates the growth performance and mucosal immunity of rainbow trout.

研究了食用葡萄（Vitis vinifera）种子提取物（GSE）对虹鳟鱼（Oncorhynchus mykiss）鱼苗生长性能和粘膜免疫参数的影响。将鱼（平均重量1.3 g）随机分配到9个水槽（每槽15条鱼）中，并饲喂含0（对照），100和200 mg kg ^-1的GSE的日粮持续60天。结果表明，与对照组相比，两个治疗组的生长参数均得到提高。鱼皮的组织学检查显示，与对照组相比，GSE组的表皮厚度，杯状细胞密度和体积密度更高。此外，相对于对照鱼，喂食GSE的鱼的肠中绒毛高度，杯状细胞密度和上皮内淋巴细胞增加。用低剂量的GSE（100 mg kg ^-1）喂养的鱼会上调一些免疫相关基因的表达，包括补体成分3（C3），溶菌酶（Lys），omDB-3，干扰素γ（IFN-γ）和肿瘤坏死因子-α（不同黏膜组织中的TNF-α）。但是，以高剂量的GSE（200 mg kg ^-1）喂鱼，大多数情况下会增强这些基因在皮肤中的表达。此外，喂食GSE的鱼的皮肤粘液对Rerseria ruckeri具有杀菌活性。结论是，GSE，特别是在100 mg kg ^-1时，可调节虹鳟鱼的生长性能和粘膜免疫力。