Yilmaz Sevdan, Kenanoğlu Osman Nezih, Ergün Sebahattin, Çelik Ekrem Şanver, Gürkan Mert, Mehana Elsayed Eldeeb, Abdel-Latif Hany M R
Department of Aquaculture, Faculty of Marine Sciences and Technology, Çanakkale Onsekiz Mart University, Çanakkale 17100, Türkiye.
Department of Food Engineering, Faculty of Engineering and Architecture, Kastamonu University, Kastamonu 37150, Türkiye.
Animals (Basel). 2024 Nov 25;14(23):3402. doi: 10.3390/ani14233402.
A 45-day feeding study was carried out to assess the immune-stimulatory effects of capsicum oleoresin when added to rainbow trout diets. A total of 450 fish (mean weight: 155.20 ± 1.96 g) were distributed into 400 L tanks (30 fish/tank) across five experimental groups: control (CT, 0%), C7 (0.7%), C14 (1.4%), C21 (2.1%), and C28 (2.8%). Each group consisted of three replicate tanks. At the end of this period, hemato-biochemical parameters, innate immune responses, and immune-related gene expression levels were evaluated, and a histological examination of head kidney and liver sections was conducted. Finally, fish in all groups were challenged with and observed for an additional 20 days. The results revealed that oleoresin supplementation enhanced the immune responses of the treated fish, which was evidenced by the increased globulin, total protein, respiratory burst activity, and total immunoglobulin levels. The highest expression levels of the , , , and genes was noticed in the C7 group, as compared with the results for the other groups. The gene expression levels were higher in all experimental groups than in the CT group, and this increase was at the highest level in the C28 group. Following the bacterial challenge, all experimental groups displayed higher survival rates compared to that of the CT group. These values were 75.93, 72.22, 46.30, 33.33, and 29.63% in the C7, C14, C21, C28, and CT groups, respectively, with the C7 group displaying the highest survival rate among the groups. The histological examination of liver and head kidney tissues revealed that higher doses (in the C21 and C28 groups) showed an increase in cytoplasmic vacuolization, which causes adverse effects on fish health. However, the C7 group displayed normal histological structure in both tissues. Taken together, the most favorable immune responses were achieved in the C7 group, suggesting that 0.7% oleoresin could be applied to rainbow trout to boost immunity and protect the fish from diseases.
进行了一项为期45天的饲养研究，以评估辣椒油树脂添加到虹鳟鱼饲料中时的免疫刺激作用。总共450条鱼（平均体重：155.20±1.96克）被分配到400升的水箱中（每箱30条鱼），分为五个实验组：对照组（CT，0%）、C7（0.7%）、C14（1.4%）、C21（2.1%）和C28（2.8%）。每组由三个重复水箱组成。在此期间结束时，评估了血液生化参数、先天免疫反应和免疫相关基因表达水平，并对头肾和肝脏切片进行了组织学检查。最后，对所有组的鱼进行 攻击，并额外观察20天。结果显示，添加辣椒油树脂增强了处理组鱼的免疫反应，球蛋白、总蛋白、呼吸爆发活性和总免疫球蛋白水平的增加证明了这一点。与其他组的结果相比，C7组中 、 、 和 基因的表达水平最高。所有实验组中的 基因表达水平均高于CT组，且在C28组中这种增加处于最高水平。细菌攻击后，所有实验组的存活率均高于CT组。C7、C14、C21、C28和CT组的这些值分别为75.93%、72.22%、46.30%、33.33%和29.63%，其中C7组在各组中存活率最高。肝脏和头肾组织的组织学检查显示，较高剂量组（C21和C28组）出现细胞质空泡化增加，这对鱼的健康产生不利影响。然而，C7组在这两种组织中均显示出正常的组织结构。综上所述，C7组实现了最有利的免疫反应，表明0.7%的辣椒油树脂可应用于虹鳟鱼以增强免疫力并保护鱼免受疾病侵害。
