The objective of this study was to evaluate the effect of fish meal replacement with a mixture of plant, and animal protein supplemented with a commercial nucleotide NucleoforceFish™, on growth, feed utilization, whole-body composition, biometric indices; liver mitochondrial enzyme activities, selected gene expression and influence on the gut microbiome of gilthead seabream, Sparus aurata. Six hundred and thirty gilthead seabream with an average initial body weight of 0.358 ± 0.002 g/fish, were used. Six experimental diets were formulated to be isonitrogenous, 45% crude protein (CP) and isocaloric 20 MJ/kg gross energy (GE). The control diet (D1) contained 25% of fish meal (FM₂₅) and had no NucleoforceFish™ added (FM₂₅/₀), diets 2-3 contained FM at a level of 25% and supplemented with 250 (FM_25/250) and 500 (FM_25/500) mg/kg NucleoforceFish™, respectively. Diets 4-6 were a non-fishmeal formulation and had no NucleoforceFish™, (diet 4, FM_0/0), 0%FM with 250mg/kg NucleoforceFish™ (diet 5, FM_0/250), and 0%FM with 500mg/kg NucleoforceFish™ (diet 6, FM_0/500). The results revealed that dietary nucleotides supplemented at 250mg/kg or 500mg/kg enhanced final body weight, weight gain, and specific growth rate of seabream either with dietary level of 25% FM diet (FM₂₅) or non-fishmeal diet (FM₀). All mitochondrial liver complex enzyme activities were recorded as having a significant positive response to the nucleotide dietary supplement. Gilthead seabream fingerlings fed FM_0/250 diet for 150 days had significantly elevated liver mitochondrial enzyme (Complex III, Complex IV, Complex I and II) activities. In addition, gilthead seabream fed FM_0/500 had significantly increased the gene expression of TCR-B and IL1-B, while fish fed FM25/250 increased significantly the gene expression of IGF1, while fish fed FM25/500 increased significantly the gene expression of Hepcidin (Hep) and the iron homeostasis hormone. There was a marked influence on specific bacteria comprising the gut microbiome namely Photobacterium; damselae; Vibrio anguillarum; Lactobacillus plantarum; Lactobacillus Enterococcus faecium subtilis. It can be concluded that FM_25/250 and FM_25/500 diets are expressing the best result, which explains that FM must be in the feed of gilthead seabream, and addition of NucleoforceFish™ at 250 mg/kg feed may further increase the performance.

这项研究的目的是评估用植物混合物和补充有商业核苷酸NucleoforceFish™的动物蛋白替代鱼粉对生长，饲料利用率，全身成分，生物测定指标的影响。肝脏线粒体酶活性，基因选择表达及其对金头鲷鲷鱼肠道微生物组的影响。使用了630只金头鲷，平均初始体重为0.358±0.002 g /鱼。六种实验饮食被配制为等氮，45％的粗蛋白（CP）和等热量20 MJ / kg总能量（GE）。对照饮食（D1）含有鱼粉的25％（FM ₂₅），也没有NucleoforceFish™加入（FM ₂₅ / ₀），饮食2-3中的FM含量为25％，并分别补充了250（FM _25/250）和500（FM _25/500）mg / kg NucleoforceFish™。饮食4-6是非鱼粉配方，不含NucleoforceFish™（饮食4，FM _0/0），0％FM（含250mg / kg NucleoforceFish™（饮食5，FM _0/250）和0％FM） 500mg / kg NucleoforceFish™（饮食6，FM _0/500）。结果表明，饮食水平为25％FM饮食（FM ₂₅）或非鱼粉饮食（FM ₀）时，补充250mg / kg或500mg / kg的饮食核苷酸可提高鲷鱼的最终体重，体重增加和比增长率。）。记录所有线粒体肝复合酶活性对核苷酸饮食补充剂具有显着的阳性反应。饲喂FM _0/250饮食150天的金头鲷鱼种的肝线粒体酶（复合物III，复合物IV，复合物I和II）活性显着升高。此外，金头鲷馈送FM _0/500已显著增加TCR-B和IL1-的基因表达乙，而鱼喂FM25 / 250显著增加IGF1的基因表达，而鱼喂FM25 / 500显著增加基因表达铁调素（Hep）和铁稳态激素。对构成肠道微生物组的特定细菌即光细菌有显着影响;丹瑟拉; 鳗弧菌; 植物乳杆菌; 枯草杆菌肠球菌。可以得出结论，FM _25/250和FM _25/500饮食表现出最好的结果，这说明FM必须在金头鲷的饲料中，并且以250 mg / kg的饲料添加NucleoforceFish™可以进一步提高性能。