This study was performed to investigate the effects of dietary acetic acid, probiotic protexin, and their combination on growth performance, intestinal microbiota, digestive enzymes, immune responses, and fatty acids composition in Siberian sturgeon. A total of 120 healthy fish with an average body weight of 54.85 ± 0.36 g were randomly divided into 4 experimental groups of 3 replicates. Fish were fed with four experimental diets as follows: control diet (diet 1), and control diet supplemented with 2% acetic acid (diet 2), 0.01% protexin (diet 3), and the combination of 2% acetic acid and 0.01% protexin (diet 4). Fish were hand-fed to apparent satiation three times a day (8:00, 15:00, and 21:00) for 62 days. Our results indicated that fish received diets 2 and 4 showed the highest final body weight, weight gain, and specific growth rate (P < 0.05). The feed conversion ratio was significantly lower in the group fed on diet 4 than the other groups (P < 0.05). Administration of diet 4 significantly decreased pH of the gut, while increased gut total viable and lactic acid bacteria, and enhanced chymotrypsin, trypsin, lipase, and amylase activity compared to other diets (P ˂ 0.05). Fish in the group received diet 2 demonstrated significantly higher activities of lysozyme and alternative complement compared with other experimental groups (P < 0.05). Administration of diets 2 and 4 significantly modified muscle n-3/n-6 and docosahexaenoic acid/eicosapentaenoic acid ratios (P < 0.05). This study indicated that incorporating diet with acetic acid, alone or supplemented with protexin, had promising results as functional feed additives in A. baerii, and can be taken in account as fish diet supplementation for its growth stimulants effects.

进行这项研究的目的是研究日粮乙酸，益生菌蛋白质及其组合对西伯利亚st鱼生长性能，肠道菌群，消化酶，免疫反应和脂肪酸组成的影响。将平均体重为54.85±0.36 g的120条健康鱼随机分为4个实验组，每组3个重复。给鱼类喂食以下四种实验饮食：对照饮食（饮食1）和补充2％乙酸（饮食2），0.01％蛋白质蛋白（饮食3）以及2％乙酸和0.01％的混合物的对照饮食protexin（饮食4）。每天三天（8：00、15：00和21:00）以人工方式喂鱼至饱食，持续62天。我们的结果表明，接受饮食2和4的鱼显示出最高的最终体重，体重增加和特定生长率（P  <0.05）。以饮食4喂养的组的饲料转化率显着低于其他组（P  <0.05）。与其他日粮相比，日粮4的施用显着降低了肠道的pH值，同时增加了肠道的总生存细菌和乳酸菌，并提高了胰凝乳蛋白酶，胰蛋白酶，脂肪酶和淀粉酶的活性（P˂0.05）。与其他实验组相比，接受饮食2的组中的鱼表现出了更高的溶菌酶和替代补体活性（P <  0.05）。饮食2和4的施用显着改变了肌肉n-3 / n-6和二十二碳六烯酸/二十碳五烯酸的比例（P <0.05）。这项研究表明，掺入饮食与乙酸，单独或补充有protexin，有希望的结果，如功能性饲料添加剂A.西伯利亚鲟，并且可以在帐户被视为鱼饮食补充其生长刺激作用。