Department of Poultry and Fish Diseases, Faculty of Veterinary Medicine, Alexandria University, Alexandria, Egypt.
Department of Fish Biology and Ecology, Central Laboratory for Aquaculture Research, Agriculture Research Center, Abbassa, Abo-Hammad, Sharqia, 44662, Egypt.
Fish Shellfish Immunol. 2021 Apr;111:111-118. doi: 10.1016/j.fsi.2021.01.013. Epub 2021 Jan 25.
Black soldier fly larvae meal (BSFLM) has been successfully demonstrated as a promising fish meal (FM) replacer in diets of several fish species including European seabass (Dicentrarchus labrax). However, its impacts on antioxidant capacity, and immune responses of treated fish are still poorly understood. A 60-day feeding trial was carried out to evaluate the effects of partial substitution of FM with different levels of dry BSFLM on the antioxidative status, non-specific immunity, transcriptomic responses, and resistance of European seabass to the challenge with Vibrio alginolyticus. Four isoproteic (45%) and isolipidic diets were formulated by replacing 0.0%, 25%, 35%, and 50% of the dietary FM. Each diet was randomly assigned to four fish groups (in triplicates) (initial mean body weight, 12.1 ± 0.21 g) (20 fish per aquarium) (n = 240). Fish were fed three times daily to the apparent satiation. At the end of the feeding trial, serum antioxidant biomarkers such as malondialdehyde levels, and catalase, superoxide dismutase, and glutathione peroxidase enzyme activities were significantly increased in all BSFLM groups in a dose-dependent manner compared to the control group (P < 0.05). The non-specific immune indices, including phagocytic activity, phagocytic index, serum lysozyme and respiratory burst activities were significantly elevated in BSFLM groups compared to those in the control group (P < 0.05). Significant upregulation of the mRNA expression levels of hepatic heat shock protein 70, interleukin-1beta and interleukin-10 genes were observed in all BSFLM groups compared to the control group (P < 0.05). Additionally, after the challenge with V. alginolyticus, the relative percent of survival was significantly elevated in fish groups fed on diets containing graded levels of BSFLM over the control group (P < 0.05). Conclusively, the present study suggests the potential efficacy of partial replacement of dietary FM protein for up to 50% by BSFLM without negative effects on fish health with possible potentiation of the antioxidative status, and the immune responses of the European seabass.
黑蝇幼虫粉（BSFLM）已成功证明可作为多种鱼类（包括欧洲鲈鱼（Dicentrarchus labrax））饲料中鱼粉（FM）的有前途的替代品。然而，其对处理过的鱼类的抗氧化能力和免疫反应的影响仍知之甚少。进行了为期 60 天的喂养试验，以评估用不同水平的干 BSFLM 替代部分 FM 对欧洲鲈鱼的抗氧化状态、非特异性免疫、转录组反应和对溶藻弧菌挑战的抵抗力的影响。通过用 0.0%、25%、35%和 50%的饲料 FM 替代，配制了四种等蛋白（45%）和等脂的饲料。将每种饲料随机分配给四个鱼类组（每组 3 个重复）（初始平均体重为 12.1±0.21g）（每个水族箱 20 条鱼）（n=240）。鱼每天喂食三次，直到吃饱为止。在喂养试验结束时，与对照组相比，所有 BSFLM 组的血清抗氧化生物标志物，如丙二醛水平以及过氧化氢酶、超氧化物歧化酶和谷胱甘肽过氧化物酶的活性均呈剂量依赖性显著增加（P<0.05）。与对照组相比，BSFLM 组的非特异性免疫指数，包括吞噬活性、吞噬指数、血清溶菌酶和呼吸爆发活性均显著升高（P<0.05）。与对照组相比，所有 BSFLM 组的肝热休克蛋白 70、白细胞介素-1β和白细胞介素-10 基因的 mRNA 表达水平均显著上调（P<0.05）。此外，在用溶藻弧菌进行攻毒后，与对照组相比，摄食含有分级 BSFLM 水平的饲料的鱼类组的相对存活率显著升高（P<0.05）。总之，本研究表明，用 BSFLM 替代高达 50%的饲料 FM 蛋白对鱼类健康没有负面影响，同时可能增强欧洲鲈鱼的抗氧化状态和免疫反应。
